Summary:
Fixes an ISel failure when a splatted load is used more than once. The
failure was due to the hacks we were doing in ISel lowering to
preserve the original load as the operand of a LOAD_SPLAT node. The
fix is to properly lower the splatted use of the load to a separate
LOAD_SPLAT node.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69640
Summary:
The SIMD spec does not include i64x2 comparisons, so they need to be
expanded. Using setOperationAction to expand them also causes f64x2
comparisons to be expanded, so setCondCodeAction needs to be used
instead. But since there are no legal condition codes, the legalizer
does not know how to expand the comparisons. We therefore manually
unroll the operation, taking care to fill each lane with -1 or 0
rather than 1 or 0 for consistency with the other vector comparisons.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69604
MipsMCAsmInfo was using '$' prefix for Mips32 and '.L' for Mips64
regardless of -target-abi option. By passing MCTargetOptions to MCAsmInfo
we can find out Mips ABI and pick appropriate prefix.
Tags: #llvm, #clang, #lldb
Differential Revision: https://reviews.llvm.org/D66795
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790
Reviewers: courbet
Subscribers: arsenm, dschuff, jyknight, sdardis, jvesely, nhaehnle, sbc100, jgravelle-google, hiraditya, aheejin, fedor.sergeev, jrtc27, atanasyan, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69216
llvm-svn: 375398
MachineInstr.h included AliasAnalysis.h, which includes a world of IR
constructs mostly unneeded in CodeGen. Prune it. Same for
DebugInfoMetadata.h.
Noticed with -ftime-trace.
llvm-svn: 375311
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790
Reviewers: courbet
Subscribers: jholewinski, arsenm, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, sbc100, jgravelle-google, hiraditya, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, Jim, lenary, s.egerton, pzheng, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68993
llvm-svn: 375084
Summary:
Renames `ExprType` to the more apt `BlockType` and adds a variant for
multivalue blocks. Currently non-void blocks are only generated at the
end of functions where the block return type needs to agree with the
function return type, and that remains true for multivalue
blocks. That invariant means that the actual signature does not need
to be stored in the block signature `MachineOperand` because it can be
inferred by `WebAssemblyMCInstLower` from the return type of the
parent function. `WebAssemblyMCInstLower` continues to lower block
signature operands to immediates when possible but lowers multivalue
signatures to function type symbols. The AsmParser and Disassembler
are updated to handle multivalue block types as well.
Reviewers: aheejin, dschuff, aardappel
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68889
llvm-svn: 374933
Summary:
The WebAssembly backend lowers fptoint instructions to a code sequence
that checks for overflow to avoid traps because fptoint is supposed to
be speculatable. These new builtins and intrinsics give users a way to
depend on the trapping semantics of the underlying instructions and
avoid the extra code generated normally.
Patch by coffee and tlively.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D68902
llvm-svn: 374856
In loop-vectorize, interleave count and vector factor depend on target register number. Currently, it does not
estimate different register pressure for different register class separately(especially for scalar type,
float type should not be on the same position with int type), so it's not accurate. Specifically,
it causes too many times interleaving/unrolling, result in too many register spills in loop body and hurting performance.
So we need classify the register classes in IR level, and importantly these are abstract register classes,
and are not the target register class of backend provided in td file. It's used to establish the mapping between
the types of IR values and the number of simultaneous live ranges to which we'd like to limit for some set of those types.
For example, POWER target, register num is special when VSX is enabled. When VSX is enabled, the number of int scalar register is 32(GPR),
float is 64(VSR), but for int and float vector register both are 64(VSR). So there should be 2 kinds of register class when vsx is enabled,
and 3 kinds of register class when VSX is NOT enabled.
It runs on POWER target, it makes big(+~30%) performance improvement in one specific bmk(503.bwaves_r) of spec2017 and no other obvious degressions.
Differential revision: https://reviews.llvm.org/D67148
llvm-svn: 374634
Summary:
This is necessary and sufficient to get simple cases of multiple
return working with multivalue enabled. More complex cases will
require block and loop signatures to be generalized to potentially be
type indices as well.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68684
llvm-svn: 374235
Summary:
This clang builtin and corresponding LLVM intrinsic are necessary to
expose the exact semantics of the underlying WebAssembly instruction
to users. LLVM produces a poison value if the dynamic swizzle indices
are greater than the vector size, but the WebAssembly instruction sets
the corresponding output lane to zero. Users who depend on this
behavior can safely use this builtin.
Depends on D68527.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D68531
llvm-svn: 374189
Summary:
Adds the new v8x16.swizzle SIMD instruction as specified at
https://github.com/WebAssembly/simd/blob/master/proposals/simd/SIMD.md#swizzling-using-variable-indices.
In addition to adding swizzles as a candidate lowering in
LowerBUILD_VECTOR, also rewrites and simplifies the lowering to
minimize the number of replace_lanes necessary rather than trying to
minimize code size. This leads to more uses of v128.const instead of
splats, which is expected to increase performance.
The new code will be easier to tune once V8 implements all the vector
construction operations, and it will also be easier to add new
candidate instructions in the future if necessary.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68527
llvm-svn: 374188
Also Revert "[LoopVectorize] Fix non-debug builds after rL374017"
This reverts commit 9f41deccc0.
This reverts commit 18b6fe07bc.
The patch is breaking PowerPC internal build, checked with author, reverting
on behalf of him for now due to timezone.
llvm-svn: 374091
Summary:
When searching for local expression tree created by stackified
registers, for 'block' placement, we start the search from the previous
instruction of a BB's terminator. But in 'try''s case, we should start
from the previous instruction of a call that can throw, or a EH_LABEL
that precedes the call, because the return values of the call's previous
instructions can be stackified and consumed by the throwing call.
For example,
```
i32.call @foo
call @bar ; may throw
br $label0
```
In this case, if we start the search from the previous instruction of
the terminator (`br` here), we end up stopping at `call @bar` and place
a 'try' between `i32.call @foo` and `call @bar`, because `call @bar`
does not have a return value so it is not a local expression tree of
`br`.
But in this case, unlike when placing 'block's, we should start the
search from `call @bar`, because the return value of `i32.call @foo` is
stackified and used by `call @bar`.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68619
llvm-svn: 374073
In loop-vectorize, interleave count and vector factor depend on target register number. Currently, it does not
estimate different register pressure for different register class separately(especially for scalar type,
float type should not be on the same position with int type), so it's not accurate. Specifically,
it causes too many times interleaving/unrolling, result in too many register spills in loop body and hurting performance.
So we need classify the register classes in IR level, and importantly these are abstract register classes,
and are not the target register class of backend provided in td file. It's used to establish the mapping between
the types of IR values and the number of simultaneous live ranges to which we'd like to limit for some set of those types.
For example, POWER target, register num is special when VSX is enabled. When VSX is enabled, the number of int scalar register is 32(GPR),
float is 64(VSR), but for int and float vector register both are 64(VSR). So there should be 2 kinds of register class when vsx is enabled,
and 3 kinds of register class when VSX is NOT enabled.
It runs on POWER target, it makes big(+~30%) performance improvement in one specific bmk(503.bwaves_r) of spec2017 and no other obvious degressions.
Differential revision: https://reviews.llvm.org/D67148
llvm-svn: 374017
Summary:
There was a bug when computing the number of unwind destination
mismatches in CFGStackify. When there are many mismatched calls that
share the same (original) destination BB, they have to be counted
separately.
This also fixes a typo and runs `fixUnwindMismatches` only when the wasm
exception handling is enabled. This is to prevent unnecessary
computations and does not change behavior.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68552
llvm-svn: 373975
Summary:
Previously, `WebAssembly::mayThrow()` assumed all inputs are global
addresses. But when intrinsics, such as `memcpy`, `memmove`, or `memset`
are lowered to external symbols in instruction selection and later
emitted as library calls. And these functions don't throw.
This patch adds handling to those memory intrinsics to `mayThrow`
function. But while most of libcalls don't throw, we can't guarantee all
of them don't throw, so currently we conservatively return true for all
other external symbols.
I think a better way to solve this problem is to embed 'nounwind' info
in `TargetLowering::CallLoweringInfo`, so that we can access the info
from the backend. This will also enable transferring 'nounwind'
properties of LLVM IR instructions. Currently we don't transfer that
info and we can only access properties of callee functions, if the
callees are within the module. Other targets don't need this info in the
backend because they do all the processing before isel, but it will help
us because that info will reduce code size increase in fixing unwind
destination mismatches in CFGStackify.
But for now we return false for these memory intrinsics and true for all
other libcalls conservatively.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68553
llvm-svn: 373967
Summary:
64-bit WebAssembly (wasm64) is not specified and not supported in the
WebAssembly backend. We do have support for it in clang, however, and
we would like to keep that support because we expect wasm64 to be
specified and supported in the future. For now add an error when
trying to use wasm64 from the backend to minimize user confusion from
unexplained crashes.
Reviewers: aheejin, dschuff, sunfish
Subscribers: sbc100, jgravelle-google, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68254
llvm-svn: 373493
Summary:
In CFGSort, we try to make EH pads have higher priorities as soon as
they are ready to be sorted, to prevent creation of unwind destination
mismatches in CFGStackify. We did that by making priority queues'
comparison function prefer EH pads, but it was possible for an EH pad
to be popped from `Preferred` queue and then not sorted immediately and
enter `Ready` queue instead in a certain condition. This patch makes
sure that special condition does not consider EH pads as its candidates.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68229
llvm-svn: 373302
Summary:
Fixing unwind mismatches for exception handling can result in splicing
existing BBs and moving some of instructions to new BBs. In this case
some of stackified def registers in the original BB can be used in the
split BB. For example, we have this BB and suppose %r0 is a stackified
register.
```
bb.1:
%r0 = call @foo
... use %r0 ...
```
After fixing unwind mismatches in CFGStackify, `bb.1` can be split and
some instructions can be moved to a newly created BB:
```
bb.1:
%r0 = call @foo
bb.split (new):
... use %r0 ...
```
In this case we should make %r0 un-stackified, because its use is now in
another BB.
When spliting a BB, this CL unstackifies all def registers that have
uses in the new split BB.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68218
llvm-svn: 373301
Summary:
Instead of having different v128.load and v128.store instructions for
each MVT, just have one of each that is reused in all the
patterns. Also removes the HasSIMD128 predicate where accompanied by
HasUnimplementedSIMD128, since the latter implies the former.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67930
llvm-svn: 372792
Summary:
Adds the new load_splat instructions as specified at
https://github.com/WebAssembly/simd/blob/master/proposals/simd/SIMD.md#load-and-splat.
DAGISel does not allow matching multiple copies of the same load in a
single pattern, so we use a new node in WebAssemblyISD to wrap loads
that should be splatted.
Depends on D67783.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67784
llvm-svn: 372655
Summary:
Removes duplicated SIMD loads and store instructions and removes
patterns involving GlobalAddresses that were not used in any tests.
Reviewers: aheejin, sunfish
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67783
llvm-svn: 372648
This reverts r372314, reapplying r372285 and the commits which depend
on it (r372286-r372293, and r372296-r372297)
This was missing one switch to getTargetConstant in an untested case.
llvm-svn: 372338
This broke the Chromium build, causing it to fail with e.g.
fatal error: error in backend: Cannot select: t362: v4i32 = X86ISD::VSHLI t392, Constant:i8<15>
See llvm-commits thread of r372285 for details.
This also reverts r372286, r372287, r372288, r372289, r372290, r372291,
r372292, r372293, r372296, and r372297, which seemed to depend on the
main commit.
> Encode them directly as an imm argument to G_INTRINSIC*.
>
> Since now intrinsics can now define what parameters are required to be
> immediates, avoid using registers for them. Intrinsics could
> potentially want a constant that isn't a legal register type. Also,
> since G_CONSTANT is subject to CSE and legalization, transforms could
> potentially obscure the value (and create extra work for the
> selector). The register bank of a G_CONSTANT is also meaningful, so
> this could throw off future folding and legalization logic for AMDGPU.
>
> This will be much more convenient to work with than needing to call
> getConstantVRegVal and checking if it may have failed for every
> constant intrinsic parameter. AMDGPU has quite a lot of intrinsics wth
> immarg operands, many of which need inspection during lowering. Having
> to find the value in a register is going to add a lot of boilerplate
> and waste compile time.
>
> SelectionDAG has always provided TargetConstant for constants which
> should not be legalized or materialized in a register. The distinction
> between Constant and TargetConstant was somewhat fuzzy, and there was
> no automatic way to force usage of TargetConstant for certain
> intrinsic parameters. They were both ultimately ConstantSDNode, and it
> was inconsistently used. It was quite easy to mis-select an
> instruction requiring an immediate. For SelectionDAG, start emitting
> TargetConstant for these arguments, and using timm to match them.
>
> Most of the work here is to cleanup target handling of constants. Some
> targets process intrinsics through intermediate custom nodes, which
> need to preserve TargetConstant usage to match the intrinsic
> expectation. Pattern inputs now need to distinguish whether a constant
> is merely compatible with an operand or whether it is mandatory.
>
> The GlobalISelEmitter needs to treat timm as a special case of a leaf
> node, simlar to MachineBasicBlock operands. This should also enable
> handling of patterns for some G_* instructions with immediates, like
> G_FENCE or G_EXTRACT.
>
> This does include a workaround for a crash in GlobalISelEmitter when
> ARM tries to uses "imm" in an output with a "timm" pattern source.
llvm-svn: 372314
Encode them directly as an imm argument to G_INTRINSIC*.
Since now intrinsics can now define what parameters are required to be
immediates, avoid using registers for them. Intrinsics could
potentially want a constant that isn't a legal register type. Also,
since G_CONSTANT is subject to CSE and legalization, transforms could
potentially obscure the value (and create extra work for the
selector). The register bank of a G_CONSTANT is also meaningful, so
this could throw off future folding and legalization logic for AMDGPU.
This will be much more convenient to work with than needing to call
getConstantVRegVal and checking if it may have failed for every
constant intrinsic parameter. AMDGPU has quite a lot of intrinsics wth
immarg operands, many of which need inspection during lowering. Having
to find the value in a register is going to add a lot of boilerplate
and waste compile time.
SelectionDAG has always provided TargetConstant for constants which
should not be legalized or materialized in a register. The distinction
between Constant and TargetConstant was somewhat fuzzy, and there was
no automatic way to force usage of TargetConstant for certain
intrinsic parameters. They were both ultimately ConstantSDNode, and it
was inconsistently used. It was quite easy to mis-select an
instruction requiring an immediate. For SelectionDAG, start emitting
TargetConstant for these arguments, and using timm to match them.
Most of the work here is to cleanup target handling of constants. Some
targets process intrinsics through intermediate custom nodes, which
need to preserve TargetConstant usage to match the intrinsic
expectation. Pattern inputs now need to distinguish whether a constant
is merely compatible with an operand or whether it is mandatory.
The GlobalISelEmitter needs to treat timm as a special case of a leaf
node, simlar to MachineBasicBlock operands. This should also enable
handling of patterns for some G_* instructions with immediates, like
G_FENCE or G_EXTRACT.
This does include a workaround for a crash in GlobalISelEmitter when
ARM tries to uses "imm" in an output with a "timm" pattern source.
llvm-svn: 372285
Summary:
Large slowdowns were observed in Rust due to many small, constant
sized copies in conjunction with poorly-optimized memory.copy
implementations. Since memory.copy cannot be expected to be inlined
efficiently by engines at this time, stop using it for the smallest
copies. We continue to lower all memcpy intrinsics to memory.copy,
though.
Reviewers: aheejin, alexcrichton
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, JDevlieghere, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67639
llvm-svn: 372275
* Reordered MVT simple types to group scalable vector types
together.
* New range functions in MachineValueType.h to only iterate over
the fixed-length int/fp vector types.
* Stopped backends which don't support scalable vector types from
iterating over scalable types.
Reviewers: sdesmalen, greened
Reviewed By: greened
Differential Revision: https://reviews.llvm.org/D66339
llvm-svn: 372099
Summary:
This is the first change to enable the TLI to be built per-function so
that -fno-builtin* handling can be migrated to use function attributes.
See discussion on D61634 for background. This is an enabler for fixing
handling of these options for LTO, for example.
This change should not affect behavior, as the provided function is not
yet used to build a specifically per-function TLI, but rather enables
that migration.
Most of the changes were very mechanical, e.g. passing a Function to the
legacy analysis pass's getTLI interface, or in Module level cases,
adding a callback. This is similar to the way the per-function TTI
analysis works.
There was one place where we were looking for builtins but not in the
context of a specific function. See FindCXAAtExit in
lib/Transforms/IPO/GlobalOpt.cpp. I'm somewhat concerned my workaround
could provide the wrong behavior in some corner cases. Suggestions
welcome.
Reviewers: chandlerc, hfinkel
Subscribers: arsenm, dschuff, jvesely, nhaehnle, mehdi_amini, javed.absar, sbc100, jgravelle-google, eraman, aheejin, steven_wu, george.burgess.iv, dexonsmith, jfb, asbirlea, gchatelet, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66428
llvm-svn: 371284
Summary:
This removes all string constants for function names and compares
functions by string directly when needed. Many of these constants are
used only once or twice so the benefit of defining them separately is
not very clear, and this actually fixes a bug.
When we already have a `malloc` declaration which is an alias to
something else within the module,
```
@malloc = weak hidden alias i8* (i32), i8* (i32)* @dlmalloc
```
(this happens compiling with emscripten with `-s WASM_OBJECT_FILES=0`
because all bc files are merged before being fed into `wasm-ld` which
runs the backend optimizations as LTO)
`Module::getFunction("malloc")` in `canLongjmp` returns `nullptr`
because `Module::getFunction` dyncasts pointer into `Function`, but the
alias is a `GlobalValue` but not a `Function`. This makes `canLongjmp`
return false for `malloc` in this case, and we end up adding a lot of
longjmp handling code around malloc. This is not only a code size
increase but actually a bug because `malloc` is used in the entry block
when preparing for setjmp tables for emscripten sjlj handling, and this
makes initial setjmp preparation, which has to happen in the entry
block, move to another split block, and this interferes with SSA update
later.
This also adds two more functions, `getTempRet0` and `setTempRet0`, in
the list of not longjmp-able functions.
Fixes https://github.com/emscripten-core/emscripten/issues/8935.
Reviewers: sbc100
Subscribers: mehdi_amini, jgravelle-google, hiraditya, sunfish, dexonsmith, dschuff, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67129
llvm-svn: 370828
Summary:
Adds clang builtins and LLVM intrinsics for these experimental
instructions. They are not implemented in engines yet, but that is ok
because the user must opt into using them by calling the builtins.
Reviewers: aheejin, dschuff
Reviewed By: aheejin
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D67020
llvm-svn: 370556
Add an WASM_SYMBOL_NO_STRIP flag, so that __attribute__((used)) doesn't
need to imply exporting. When targeting Emscripten, have
WASM_SYMBOL_NO_STRIP imply exporting.
Differential Revision: https://reviews.llvm.org/D62542
llvm-svn: 370415
Summary:
Previously we skipped uses within the same BB as a def when rebuilding
SSA after SjLj transformation. For example, before transformation,
```
for.cond:
%0 = phi i32 [ %var, %for.inc ] ...
%var = ...
br label %for.inc
for.inc: ; preds = %for.cond
call i32 @setjmp(...)
br %for.cond
```
In this BB, %var should be defined in all paths from %for.inc to make %0
valid. In the input it was true; %for.inc's only predecessor was
%for.cond. But after SjLj transformation, it is possible that %for.inc
has other predecessors that are reachable without reaching %for.cond.
```
entry.split:
...
br i1 %a, label %bb.1, label %for.inc
for.cond:
%0 = phi i32 [ %var, %for.inc ] ... ; Not valid!
%var = ...
br label %for.inc
for.inc: ; preds = %for.cond, %entry.split
call i32 @setjmp(...)
...
br %for.cond
```
In this case, we can't use %var in the `phi` instruction in %for.cond,
because %var is not defined in all paths through %for.inc (If the
control flow is %entry -> %entry.split -> %for.inc -> %for.cond, %var
has not been defined until we reach the `phi`). But the previous code
excluded users within the same BB, skipping instructions within the same
BB so they are not rewritten properly. User instructions within the same
BB also should be candidates for rewriting if they are _before_ the
original definition.
Fixes PR43097.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66729
llvm-svn: 369978
I noticed another instance of the issue where references to aliases were
being replaced with aliasees, this time in InstCombine. In the instance that
I saw it turned out to be only a QoI issue (a symbol ended up being missing
from the symbol table due to the last reference to the alias being removed,
preventing HWASAN from symbolizing a global reference), but it could easily
have manifested as incorrect behaviour.
Since this is the third such issue encountered (previously: D65118, D65314)
it seems to be time to address this common error/QoI issue once and for all
and make the strip* family of functions not look through aliases.
Includes a test for the specific issue that I saw, but no doubt there are
other similar bugs fixed here.
As with D65118 this has been tested to make sure that the optimization isn't
load bearing. I built Clang, Chromium for Linux, Android and Windows as well
as the test-suite and there were no size regressions.
Differential Revision: https://reviews.llvm.org/D66606
llvm-svn: 369697
The patch introduces MakeLibCallOptions struct as suggested by @efriedma on D65497.
The struct contain argument flags which will pass to makeLibCall function.
The patch should not has any functionality changes.
Differential Revision: https://reviews.llvm.org/D65795
llvm-svn: 369622
Summary:
We tried to support EM_ASM with setjmp/longjmp in binaryen. But with dynamic
linking thrown into the mix, the code is no longer understandable and cannot
be maintained. We also discovered more bugs in the EM_ASM handling code.
To ensure maintainability and correctness of the binaryen code, EM_ASM will
no longer be supported with setjmp/longjmp. This is probably fine since the
support was added recently and haven't be published.
Reviewers: tlively, sbc100, jgravelle-google, kripken
Reviewed By: tlively, kripken
Subscribers: dschuff, hiraditya, aheejin, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66356
llvm-svn: 369137
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.
llvm-svn: 369013
Summary:
Fixes PR42973. Tests don't change because simd-arith.ll tests behavior
on unimplemented-simd128, which does not include any temporary
workarounds such as the one removed in this revision.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, dmgreen, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66166
llvm-svn: 368868
Summary:
While D65962 is pending for review, I landed D65475 that added one more
use of `unsigned`. Changed it to `Register`.
Reviewers: dsanders
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66064
llvm-svn: 368727
Summary:
When exceptions are repeatedly thrown in the middle of handling another
exception, we call `__clang_call_terminate` with the exception pointer
(i32) as an argument. But in case of foreign exceptions, we don't have
the pointer, so we call the function with 0. (This requires
`__clang_call_terminate` can deal with 0 argument, which will be done
later)
But previously the 0 argument was not added as a `i32.const 0` but an
immediate by mistake, causing the `call` instruction to take not an i32
but rather an exnref, because an `exnref` is left on top of the value
stack if `br_on_exn` is not taken.
```
block i32
br_on_exn 0, __cpp_exception
;; exnref is on top of stack now
i32.const 0 ;; This was missing!
call __clang_call_terminate
unreachable
end
call __clang_call_terminate ;; This takes i32 extracted by br_on_exn
```
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65475
llvm-svn: 368527
Summary:
When the WebAssembly backend encounters a return type that doesn't
fit within i32, SelectionDAG performs sret demotion, adding an
additional argument to the start of the function that contains
a pointer to an sret buffer to use instead. However, this conflicts
with the emscripten sjlj lowering pass. There we translate calls like:
```
call {i32, i32} @foo()
```
into (in pseudo-llvm)
```
%addr = @foo
call {i32, i32} @__invoke_{i32,i32}(%addr)
```
i.e. we perform an indirect call through an extra function.
However, the sret transform now transforms this into
the equivalent of
```
%addr = @foo
%sret = alloca {i32, i32}
call {i32, i32} @__invoke_{i32,i32}(%sret, %addr)
```
(while simultaneously translation the implementation of @foo as well).
Unfortunately, this doesn't work out. The __invoke_ ABI expected
the function address to be the first argument, causing crashes.
There is several possible ways to fix this:
1. Implementing the sret rewrite at the IR level as well and performing
it as part of lowering to __invoke
2. Fixing the wasm backend to recognize that __invoke has a special ABI
3. A change to the binaryen/emscripten ABI to recognize this situation
This revision implements the middle option, teaching the backend to
treat __invoke_ functions specially in sret lowering. This is achieved
by
1) Introducing a new CallingConv ID for invoke functions
2) When this CallingConv ID is seen in the backend and the first argument
is marked as sret (a function pointer would never be marked as sret),
swapping the first two arguments.
Reviewed By: tlively, aheejin
Differential Revision: https://reviews.llvm.org/D65463
llvm-svn: 367935
Summary:
This is patch is part of a serie to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790
Reviewers: courbet, jfb, jakehehrlich
Reviewed By: jfb
Subscribers: wuzish, jholewinski, arsenm, dschuff, nemanjai, jvesely, nhaehnle, javed.absar, sbc100, jgravelle-google, hiraditya, aheejin, kbarton, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, dexonsmith, PkmX, jocewei, jsji, s.egerton, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65514
llvm-svn: 367828
Summary:
The allocsize attribute refers to call parameters by index.
Thus, when we add the extra parameter in sjlj lowering, we
need to increment the referenced paramater in the allocsize
attribute to avoid angering the Verifier.
Reviewed By: aheejin
Differential Revision: https://reviews.llvm.org/D65470
llvm-svn: 367765
Summary:
Fixes: https://bugs.llvm.org/show_bug.cgi?id=42441
Used to print:
<unknown>:0: error: Cannot represent a difference across sections
(the location was null).
Now prints:
err.s:20:3: error: Cannot represent a difference across sections
i32.const foo-bar
^
Note: I looked at adding a test for this, but I don't think it is
worth it. We're not testing error formatting in the Wasm backend :)
Reviewers: sbc100, jgravelle-google
Subscribers: dschuff, aheejin, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65602
llvm-svn: 367619
A TYPE_INDEX operand (as used by call_indirect) used to be represented
by the InstPrinter as a symbol (e.g. .Ltype_index0@TYPE_INDEX) which
was a bit of a mismatch with the WasmObjectWriter which expects an
unnamed symbol, to receive the signature from and then turn into a
reloc.
There was really no good way to round-trip this information. An earlier
version of this patch tried to attach the signature information using
a .functype, but that ran into trouble when the symbol was re-emitted
without a name. Removing the name was a giant hack also.
The current version changes the assembly syntax to have an inline
signature spec for TYPEINDEX operands that is always unnamed, which
is much more elegant both in syntax and in implementation (as now the
assembler is able to follow the same path as the regular backend)
Reviewers: sbc100, dschuff, aheejin, jgravelle-google, sunfish, tlively
Subscribers: arphaman, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64758
llvm-svn: 367590
Summary:
While there is always a `Value::replaceAllUsesWith()`,
sometimes the replacement needs to be conditional.
I have only cleaned a few cases where `replaceUsesWithIf()`
could be used, to both add test coverage,
and show that it is actually useful.
Reviewers: jdoerfert, spatel, RKSimon, craig.topper
Reviewed By: jdoerfert
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, aheejin, george.burgess.iv, asbirlea, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65528
llvm-svn: 367548
Summary:
return_call and return_call_indirect are only valid if the return
types of the callee and caller match. We were previously not enforcing
that, which was producing invalid modules.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65246
llvm-svn: 367339
Summary:
Add immutable WASM global `__tls_align` which stores the alignment
requirements of the TLS segment.
Add `__builtin_wasm_tls_align()` intrinsic to get this alignment in Clang.
The expected usage has now changed to:
__wasm_init_tls(memalign(__builtin_wasm_tls_align(),
__builtin_wasm_tls_size()));
Reviewers: tlively, aheejin, sbc100, sunfish, alexcrichton
Reviewed By: tlively
Subscribers: dschuff, jgravelle-google, hiraditya, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D65028
llvm-svn: 366624
Summary:
Add `__builtin_wasm_tls_base` so that LeakSanitizer can find the thread-local
block and scan through it for memory leaks.
Reviewers: tlively, aheejin, sbc100
Subscribers: dschuff, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D64900
llvm-svn: 366475
Summary:
Currently, on Emscripten, dynamic linking is not supported with threads.
This means that if thread-local storage is used, it must be used in a
statically-linked executable. Hence, local-exec is the only possible model.
This diff compiles all TLS variables to use local-exec on Emscripten as a
temporary measure until dynamic linking is supported with threads.
The goal for this is to allow C++ types with constructors to be thread-local.
Currently, when `clang` compiles a `thread_local` variable with a constructor,
it generates `__tls_guard` variable:
@__tls_guard = internal thread_local global i8 0, align 1
As no TLS model is specified, this is treated as general-dynamic, which we do
not support (and cannot support without implementing dynamic linking support
with threads in Emscripten). As a result, any C++ constructor in `thread_local`
variables would not compile.
By compiling all `thread_local` as local-exec, `__tls_guard` will compile and
we can support C++ constructors with TLS without implementing dynamic linking
with threads.
Depends on D64537
Reviewers: tlively, aheejin, sbc100
Reviewed By: aheejin
Subscribers: dschuff, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64776
llvm-svn: 366275
Summary:
Thread local variables are placed inside a `.tdata` segment. Their symbols are
offsets from the start of the segment. The address of a thread local variable
is computed as `__tls_base` + the offset from the start of the segment.
`.tdata` segment is a passive segment and `memory.init` is used once per thread
to initialize the thread local storage.
`__tls_base` is a wasm global. Since each thread has its own wasm instance,
it is effectively thread local. Currently, `__tls_base` must be initialized
at thread startup, and so cannot be used with dynamic libraries.
`__tls_base` is to be initialized with a new linker-synthesized function,
`__wasm_init_tls`, which takes as an argument a block of memory to use as the
storage for thread locals. It then initializes the block of memory and sets
`__tls_base`. As `__wasm_init_tls` will handle the memory initialization,
the memory does not have to be zeroed.
To help allocating memory for thread-local storage, a new compiler intrinsic
is introduced: `__builtin_wasm_tls_size()`. This instrinsic function returns
the size of the thread-local storage for the current function.
The expected usage is to run something like the following upon thread startup:
__wasm_init_tls(malloc(__builtin_wasm_tls_size()));
Reviewers: tlively, aheejin, kripken, sbc100
Subscribers: dschuff, jgravelle-google, hiraditya, sunfish, jfb, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D64537
llvm-svn: 366272
Summary:
This adds missing utility methods and copy instruction handling for
`exnref` type and also adds tests.
`tee` instruction tests are missing because `isTee` is currently only
used in ExplicitLocals pass and testing that pass in mir requires
serialization of stackified registers in mir files, which is a bit
nontrivial because `MachineFunctionInfo` only has info of vreg numbers
(which are large integers) but not the mir's register numbers. But this
change is quite trivial anyway.
Reviewers: tlively
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64705
llvm-svn: 366149
Summary:
We agreed to rename `except_ref` to `exnref` for consistency with other
reference types in
https://github.com/WebAssembly/exception-handling/issues/79. This also
renames WebAssemblyInstrExceptRef.td to WebAssemblyInstrRef.td in order
to use the file for other reference types in future.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64703
llvm-svn: 366145
Summary:
These are emitted as identifiers by the InstPrinter, so we should
parse them as such. These could potentially clash with symbols of
the same name, but that is out of our (the WebAssembly backend) control.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, aheejin, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64770
llvm-svn: 366139
Summary:
Most of these functions can work for MachineInstr and MCInst
equally now.
Reviewers: dschuff
Subscribers: MatzeB, sbc100, jgravelle-google, aheejin, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64643
llvm-svn: 365965
Summary:
Wasm does not currently support `llvm.clear_cache` intrinsic, and this
prints a proper error message instead of segfault.
Reviewers: dschuff, sbc100, sunfish
Subscribers: jgravelle-google, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64322
llvm-svn: 365731
Summary:
Even with functions with `no-prototype` attribute, there can be an
argument `sret` (structure return) attribute, which is an optimization
when a function return type is a struct. Fixes PR42420.
Reviewers: sbc100
Subscribers: dschuff, jgravelle-google, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64318
llvm-svn: 365426
Summary:
Before, they were one category of operands which could cause
crashes in non-sensical combinations, e.g. "f32.const symbol".
Now these are forced to be an error.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, aheejin, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64039
llvm-svn: 365351
Wasm doesn't have a direct way to lower indirectbr, so hook up the
IndirectBrExpandPass to lower indirectbr into a switch.
Fixes PR42498
Reviewers: aheejin
Differential Revision: https://reviews.llvm.org/D64161
llvm-svn: 365096
Summary:
Before, inline assembly gets mangled by the SjLj transformation.
For example, in a function with setjmp/longjmp, this LLVM IR code
call void asm sideeffect "", ""()
would be transformed into
call void @__invoke_void(void ()* asm sideeffect "", "")
This is invalid, and results in the error:
Cannot take the address of an inline asm!
In this diff, we skip the transformation for inline assembly.
Reviewers: aheejin, tlively
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64115
llvm-svn: 364985
Summary:
- Match the syntax output by InstPrinter.
- Fix it always emitting 0 for align. Had to work around fact that
opcode is not available for GetDefaultP2Align while parsing.
- Updated tests that were erroneously happy with a p2align=0
Fixes https://bugs.llvm.org/show_bug.cgi?id=40752
Reviewers: aheejin, sbc100
Subscribers: jgravelle-google, sunfish, jfb, llvm-commits, dschuff
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63633
llvm-svn: 364570
Summary:
Since the WebAssembly SIMD shift instructions take i32 operands, we
truncate the i64 operand to <2 x i64> shifts during ISel. When the i64
operand is sign extended from i32, this CL makes it so the sign
extension is dropped instead of a wrap instruction added.
Reviewers: dschuff, aheejin
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63615
llvm-svn: 364446
Summary:
Implements direct and indirect tail calls enabled by the 'tail-call'
feature in both DAG ISel and FastISel. Updates existing call tests and
adds new tests including a binary encoding test.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62877
llvm-svn: 364445
Summary:
`catch_all` is from the first version of EH proposal and now has been
removed. There were no tests covering this, and thus no tests to remove
or fix.
Reviewers: aardappel
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63737
llvm-svn: 364360
Avoids using a plain unsigned for registers throughoug codegen.
Doesn't attempt to change every register use, just something a little
more than the set needed to build after changing the return type of
MachineOperand::getReg().
llvm-svn: 364191
Summary:
Converting the result *.{all,any}_true to a bool at the source level
generates LLVM IR that compares the result to 0. This check is
redundant since these instructions already return either 0 or 1 and
therefore conform to the BooleanContents setting for WebAssembly. This
CL adds patterns to detect and remove such redundant operations on the
result of Boolean reductions.
Reviewers: dschuff, aheejin
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63529
llvm-svn: 363756
As discussed on D62910, we need to check whether particular types of memory access are allowed, not just their alignment/address-space.
This NFC patch adds a MachineMemOperand::Flags argument to allowsMemoryAccess and allowsMisalignedMemoryAccesses, and wires up calls to pass the relevant flags to them.
If people are happy with this approach I can then update X86TargetLowering::allowsMisalignedMemoryAccesses to handle misaligned NT load/stores.
Differential Revision: https://reviews.llvm.org/D63075
llvm-svn: 363179
This reverts r362990 (git commit 374571301d)
This was causing linker warnings on Darwin:
ld: warning: direct access in function 'llvm::initializeEvexToVexInstPassPass(llvm::PassRegistry&)'
from file '../../lib/libLLVMX86CodeGen.a(X86EvexToVex.cpp.o)' to global weak symbol
'void std::__1::__call_once_proxy<std::__1::tuple<void* (&)(llvm::PassRegistry&),
std::__1::reference_wrapper<llvm::PassRegistry>&&> >(void*)' from file '../../lib/libLLVMCore.a(Verifier.cpp.o)'
means the weak symbol cannot be overridden at runtime. This was likely caused by different translation
units being compiled with different visibility settings.
llvm-svn: 363028
Summary:
For builds with LLVM_BUILD_LLVM_DYLIB=ON and BUILD_SHARED_LIBS=OFF
this change makes all symbols in the target specific libraries hidden
by default.
A new macro called LLVM_EXTERNAL_VISIBILITY has been added to mark symbols in these
libraries public, which is mainly needed for the definitions of the
LLVMInitialize* functions.
This patch reduces the number of public symbols in libLLVM.so by about
25%. This should improve load times for the dynamic library and also
make abi checker tools, like abidiff require less memory when analyzing
libLLVM.so
One side-effect of this change is that for builds with
LLVM_BUILD_LLVM_DYLIB=ON and LLVM_LINK_LLVM_DYLIB=ON some unittests that
access symbols that are no longer public will need to be statically linked.
Before and after public symbol counts (using gcc 8.2.1, ld.bfd 2.31.1):
nm before/libLLVM-9svn.so | grep ' [A-Zuvw] ' | wc -l
36221
nm after/libLLVM-9svn.so | grep ' [A-Zuvw] ' | wc -l
26278
Reviewers: chandlerc, beanz, mgorny, rnk, hans
Reviewed By: rnk, hans
Subscribers: Jim, hiraditya, michaelplatings, chapuni, jholewinski, arsenm, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, javed.absar, sbc100, jgravelle-google, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, mgrang, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, kristina, jsji, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D54439
llvm-svn: 362990
The current PIC support currently only works with Emscripten, so
disable it for other targets.
This is the PIC portion of https://reviews.llvm.org/D62542.
Reviewed By: dschuff, sbc100
llvm-svn: 362638
Summary:
Adjusts the index and adds a bitcast around the vector operand of
EXTRACT_VECTOR_ELT so that its lane type matches the source type of
its parent sext_inreg. Without this bitcast the ISel patterns do not
match and ISel fails.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62646
llvm-svn: 362547
Summary:
This adds support for translation of LLVM IR fence instruction. We
convert a singlethread fence to a pseudo compiler barrier which becomes
0 instructions in final binary, and a thread fence to an idempotent
atomicrmw instruction to a memory address.
Reviewers: dschuff, jfb, sunfish, tlively
Subscribers: sbc100, jgravelle-google, llvm-commits
Differential Revision: https://reviews.llvm.org/D50277
llvm-svn: 361884
Summary:
These features will both be implemented soon, so I thought I would
save time by adding the boilerplate for both of them at the same time.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D62047
llvm-svn: 361516
Summary:
In this patch, `ISD::RETURNADDR` is lowered on the emscripten target
to the new Emscripten runtime function `emscripten_return_address`, which
implements the functionality.
Patch by Guanzhong Chen
Reviewers: tlively, aheejin
Reviewed By: tlively
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62210
llvm-svn: 361454
r360889 added new llround builtin functions. This patch adds their
signatures for the WebAssembly backend.
It also adds wasm32 support to utils/update_llc_test_checks.py, since
that's the script other targets are using for their testcases for this
feature.
Differential Revision: https://reviews.llvm.org/D62207
llvm-svn: 361327
Move the declarations of getThe<Name>Target() functions into a new header in
TargetInfo and make users of these functions include this new header.
This fixes a layering problem.
llvm-svn: 360735
Usually this will abort fast-isel at the instruction using the
non-legal result, but if the only use is in a different basic block,
we'll incorrectly assume that the zext/sext is to i32 (rather than
i128 in this case).
Differential Revision: https://reviews.llvm.org/D61823
llvm-svn: 360616
This fixes the link error
ld.lld: error: undefined symbol: llvm::WebAssembly::anyTypeToString(unsigned int)
>>> referenced by WebAssemblyDisassembler.cpp
llvm-svn: 360558
For some targets, there is a circular dependency between InstPrinter and
MCTargetDesc. Merging them together will fix this. For the other targets,
the merging is to maintain consistency so all targets will have the same
structure.
llvm-svn: 360550
We don't have FP exception limits in the IR constant folder for the binops (apart from strict ops),
so it does not make sense to have them here in the DAG either. Nothing else in the backend tries
to preserve exceptions (again outside of strict ops), so I don't see how this could have ever
worked for real code that cares about FP exceptions.
There are still cases (examples: unary opcodes in SDAG, FMA in IR) where we are trying (at least
partially) to preserve exceptions without even asking if the target supports FP exceptions. Those
should be corrected in subsequent patches.
Real support for FP exceptions requires several changes to handle the constrained/strict FP ops.
Differential Revision: https://reviews.llvm.org/D61331
llvm-svn: 359791
Add support for f16 libcalls in WebAssembly. This entails adding signatures
for the remaining F16 libcalls, and renaming gnu_f2h_ieee/gnu_h2f_ieee to
truncsfhf2/extendhfsf2 for consistency between f32 and f64/f128 (compiler-rt
already supports this).
Differential Revision: https://reviews.llvm.org/D61287
Reviewer: dschuff
llvm-svn: 359600
The WebAssembly backend needs to know the signatures of all runtime
libcall functions. This adds the signature for __stack_chk_fail which was
previously missing.
Also, make the error message for a missing libcall include the name of
the function.
Differential Revision: https://reviews.llvm.org/D59521
Reviewed By: sbc100
llvm-svn: 359505
Summary:
Targets like ARM, MSP430, PPC, and SystemZ have complex behavior when
printing the address of a MachineOperand::MO_GlobalAddress. Move that
handling into a new overriden method in each base class. A virtual
method was added to the base class for handling the generic case.
Refactors a few subclasses to support the target independent %a, %c, and
%n.
The patch also contains small cleanups for AVRAsmPrinter and
SystemZAsmPrinter.
It seems that NVPTXTargetLowering is possibly missing some logic to
transform GlobalAddressSDNodes for
TargetLowering::LowerAsmOperandForConstraint to handle with "i" extended
inline assembly asm constraints.
Fixes:
- https://bugs.llvm.org/show_bug.cgi?id=41402
- https://github.com/ClangBuiltLinux/linux/issues/449
Reviewers: echristo, void
Reviewed By: void
Subscribers: void, craig.topper, jholewinski, dschuff, jyknight, dylanmckay, sdardis, nemanjai, javed.absar, sbc100, jgravelle-google, eraman, kristof.beyls, hiraditya, aheejin, kbarton, fedor.sergeev, jrtc27, atanasyan, jsji, llvm-commits, kees, tpimh, nathanchance, peter.smith, srhines
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60887
llvm-svn: 359337
Summary:
Always convert switches to br_tables unless there is only one case,
which is equivalent to a simple branch. This reduces code size for wasm,
and we defer possible jump table optimizations to the VM.
Addresses PR41502.
Reviewers: kripken, sunfish
Subscribers: dschuff, sbc100, jgravelle-google, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60966
llvm-svn: 359038
My understanding is that once BuildMI has been called we can't fallback
to SelectionDAG.
This change moves the fallback for when getRegForValue() fails for
that target of an indirect call. This was failing in -fPIC mode when
the callee is GlobalValue.
Add a test case that tickles this.
Differential Revision: https://reviews.llvm.org/D60908
llvm-svn: 358793
Summary: This brings the backend in line with Clang.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60594
llvm-svn: 358310
Summary:
The InlineAsm::AsmDialect is only required for X86; no architecture
makes use of it and as such it gets passed around between arch-specific
and general code while being unused for all architectures but X86.
Since the AsmDialect is queried from a MachineInstr, which we also pass
around, remove the additional AsmDialect parameter and query for it deep
in the X86AsmPrinter only when needed/as late as possible.
This refactor should help later planned refactors to AsmPrinter, as this
difference in the X86AsmPrinter makes it harder to make AsmPrinter more
generic.
Reviewers: craig.topper
Subscribers: jholewinski, arsenm, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, javed.absar, sbc100, jgravelle-google, eraman, hiraditya, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, llvm-commits, peter.smith, srhines
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60488
llvm-svn: 358101
This allows __THREW__ to be defined in the current module, although
it is still required to be a GlobalVariable.
In emscripten we want to be able to compile the source code that
defines this symbols.
Previously we were avoid this by not running this pass when building
that compiler-rt library, but I have change out to build it using the
normal compiler path:
https://github.com/emscripten-core/emscripten/pull/8391
Differential Revision: https://reviews.llvm.org/D60232
llvm-svn: 357665
This change is in preparation for the addition of new target
operand flags for new relocation types. Have a symbol type as part
of the flag set makes it harder to use and AFAICT these are serving
no purpose.
Differential Revision: https://reviews.llvm.org/D60014
llvm-svn: 357548
Summary:
Linearing the control flow by placing `try`/`end_try` markers can create
mismatches in unwind destinations. This patch resolves these mismatches
by wrapping those instructions with an incorrect unwind destination with
a nested `try`/`catch`/`end_try` and branching to the right destination
within the new catch block.
Reviewers: dschuff
Subscribers: sunfish, sbc100, jgravelle-google, chrib, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D48345
llvm-svn: 357343
Summary:
While this does not change any final output, this will greatly simplify
ixing unwind destination mismatches in CFGStackify (D48345), because we
have to create some new registers there.
Reviewers: dschuff
Subscribers: sunfish, sbc100, jgravelle-google, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59652
llvm-svn: 357342
Summary:
Currently we create a routing block to the dispatch block for every
predecessor of every entry. So the total number of routing blocks
created will be (# of preds) * (# of entries). But we don't need to do
this: we need at most 2 routing blocks per loop entry, one for when the
predecessor is inside the loop and one for it is outside the loop. (We
can't merge these into one because this will creates another loop cycle
between blocks inside and blocks outside) This patch fixes this and
creates at most 2 routing blocks per entry.
This also renames variable `Split` to `Routing`, which I think is a bit
clearer.
Reviewers: kripken
Subscribers: sunfish, dschuff, sbc100, jgravelle-google, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59462
llvm-svn: 357337
Summary:
This feature is not actually used for anything in the WebAssembly
backend, but adding it allows users to get it into the target features
sections of their objects, which makes these objects
future-compatible.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, jdoerfert, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D60013
llvm-svn: 357321
Summary:
This fixes crashes when a BB in which an END_LOOP is to be placed is
unreachable and does not have any predecessors. Fixes PR41307.
Reviewers: dschuff
Subscribers: yurydelendik, sbc100, jgravelle-google, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60004
llvm-svn: 357303
Summary:
It does not currently make sense to use WebAssembly features in some functions
but not others, so this CL adds an IR pass that takes the union of all used
feature sets and applies it to each function in the module. This allows us to
prevent atomics from being lowered away if some function has opted in to using
them. When atomics is not enabled anywhere, we detect whether there exists any
atomic operations or thread local storage that would be stripped and disallow
linking with objects that contain atomics if and only if atomics or tls are
stripped. When atomics is enabled, mark it as used but do not require it of
other objects in the link. These changes allow libraries that do not use atomics
to be built once and linked into both single-threaded and multithreaded
binaries.
Reviewers: aheejin, sbc100, dschuff
Subscribers: jgravelle-google, hiraditya, sunfish, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59625
llvm-svn: 357226
These fixup kinds are not explicitly related to the code section. They
are there to signal how to apply the fixup.
Also, a couple of other minor wasm cleanups.
Differential Revision: https://reviews.llvm.org/D59908
llvm-svn: 357145
This change implements lowering of references global symbols in PIC
mode.
This change implements lowering of global references in PIC mode using a
new @GOT reference type. @GOT references can be used with function or
data symbol names combined with the get_global instruction. In this case
the linker will insert the wasm global that stores the address of the
symbol (either in memory for data symbols or in the wasm table for
function symbols).
For now I'm continuing to use the R_WASM_GLOBAL_INDEX_LEB relocation
type for this type of reference which means that this relocation type
can refer to either a global or a function or data symbol. We could
choose to introduce specific relocation types for GOT entries in the
future. See the current dynamic linking proposal:
https://github.com/WebAssembly/tool-conventions/blob/master/DynamicLinking.md
Differential Revision: https://reviews.llvm.org/D54647
llvm-svn: 357022
Summary:
`WebAssembly::analyzeBranch` now does not analyze anything if the
function is CFG stackified. We were previously doing similar things by
checking if a branch's operand is whether an integer or an MBB, but this
failed to bail out when a BB did not have any terminators.
Consider this case:
```
bb0:
try $label0
call @foo // unwinds to %ehpad
bb1:
...
br $label0 // jumps to %cont. can be deleted
ehpad:
catch
...
cont:
end_try
```
Here `br $label0` will be deleted in CFGStackify's
`removeUnnecessaryInstrs` function, because we jump to the %cont block
even without the branch. But in this case, MachineVerifier fails to
verify this, because `ehpad` is not a successor of `bb1` even if `bb1`
does not have any terminators. MachineVerifier incorrectly thinks `bb1`
falls through to the next block.
This pass now consistently rejects all analysis after CFGStackify
whether a BB has terminators or not, also making the MachineVerifier
work. (MachineVerifier does not try to verify relationships between BBs
if `analyzeBranch` fails, the behavior we want after CFGStackify.)
This also adds a new option `-wasm-disable-ehpad-sort` for testing. This
option helps create the sorted order we want to test, and without the
fix in this patch, the tests in cfg-stackify-eh.ll fail at
MachineVerifier with `-wasm-disable-ehpad-sort`.
Reviewers: dschuff
Subscribers: sunfish, sbc100, jgravelle-google, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59740
llvm-svn: 357015
Summary:
This adds `CFGStackified` field and its serialization to
WebAssemblyFunctionInfo.
Reviewers: dschuff
Subscribers: sunfish, sbc100, jgravelle-google, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59747
llvm-svn: 357011
Summary:
The framework for supporting target-specific MachineFunctionInfo was
added in r356215. This adds serialization support for
WebAssemblyFunctionInfo on top of that. This patch only adds the
framework and does not actually serialize anything at this point; we
have to add YAML mapping later for the fields in WebAssemblyFunctionInfo
we want to serialize if necessary.
Reviewers: dschuff, arsenm
Subscribers: sunfish, wdng, sbc100, jgravelle-google, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59737
llvm-svn: 357009
Summary:
When TRY and LOOP markers are in the same BB and END_TRY and END_LOOP
markers are in the same BB, END_TRY should be _before_ END_LOOP, because
LOOP is always before TRY if they are in the same BB. (TRY is placed in
the latest possible position, whereas LOOP is in the earliest possible
position.)
Reviewers: dschuff
Subscribers: sunfish, sbc100, jgravelle-google, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59751
llvm-svn: 357008
Summary:
Before we placed all TRY/END_TRY markers before placing BLOCK/END_BLOCK
markers. This couldn't handle this case:
```
bb0:
br bb2
bb1: // nearest common dominator of bb3 and bb4
br_if ... bb3
br bb4
bb2:
...
bb3:
call @foo // unwinds to ehpad
bb4:
call @bar // unwinds to ehpad
ehpad:
catch
...
```
When we placed TRY markers, we placed it in bb1 because it is the
nearest common dominator of bb3 and bb4. But because bb0 jumps to bb2,
when we placed block markers, we ended up with interleaved scopes like
```
block
try
end_block
catch
end_try
```
which was not correct.
This patch fixes the bug by placing BLOCK and TRY markers in one pass
while iterating BBs in a function. This also adds some more routines to
`placeTryMarkers`, because we now have to assume that there can be
previously placed BLOCK and END_BLOCK.
Reviewers: dschuff
Subscribers: sunfish, sbc100, jgravelle-google, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59739
llvm-svn: 357007
Class `RegionInfo` was `SortUnitInfo` before, so the variables were
named `SUI`. Now the class name is `RegionInfo`, so this renames `SUI`
to `RI`, matching the class name.
llvm-svn: 356861
Summary:
Implements a new target features section in assembly and object files
that records what features are used, required, and disallowed in
WebAssembly objects. The linker uses this information to ensure that
all objects participating in a link are feature-compatible and records
the set of used features in the output binary for use by optimizers
and other tools later in the toolchain.
The "atomics" feature is always required or disallowed to prevent
linking code with stripped atomics into multithreaded binaries. Other
features are marked used if they are enabled globally or on any
function in a module.
Future CLs will add linker flags for ignoring feature compatibility
checks and for specifying the set of allowed features, implement using
the presence of the "atomics" feature to control the type of memory
and segments in the linked binary, and add front-end flags for
relaxing the linkage policy for atomics.
Reviewers: aheejin, sbc100, dschuff
Subscribers: jgravelle-google, hiraditya, sunfish, mgrang, jfb, jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59173
llvm-svn: 356610
This will allow targets more flexibility to replace the
register allocator core passes. In a future commit,
AMDGPU will run the core register assignment passes
twice, and will also want to disallow using the
standard -regalloc option.
llvm-svn: 356506
Summary:
- Make some class member methods const
- Delete unnecessary includes
- Use a simpler form of `BuildMI`
Reviewers: kripken
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59454
llvm-svn: 356440
The default implementation does we want and is going to more compatible
with dynamic linking (-fPIC) support that is planned.
This is NFC because currently we only build wasm with
`-relocation-model=static` which in turn means that the default
`isOffsetFoldingLegal` always returns true today.
Differential Revision: https://reviews.llvm.org/D54661
llvm-svn: 356410
Summary:
In the new wasm EH proposal, `rethrow` takes an `except_ref` argument.
This change was missing in r352598.
This patch adds `llvm.wasm.rethrow.in.catch` intrinsic. This is an
intrinsic that's gonna eventually be lowered to wasm `rethrow`
instruction, but this intrinsic can appear only within a catchpad or a
cleanuppad scope. Also this intrinsic needs to be invokable - otherwise
EH pad successor for it will not be correctly generated in clang.
This also adds lowering logic for this intrinsic in
`SelectionDAGBuilder::visitInvoke`. This routine is basically a
specialized and simplified version of
`SelectionDAGBuilder::visitTargetIntrinsic`, but we can't use it
because if is only for `CallInst`s.
This deletes the previous `llvm.wasm.rethrow` intrinsic and related
tests, which was meant to be used within a `__cxa_rethrow` library
function. Turned out this needs some more logic, so the intrinsic for
this purpose will be added later.
LateEHPrepare takes a result value of `catch` and inserts it into
matching `rethrow` as an argument.
`RETHROW_IN_CATCH` is a pseudo instruction that serves as a link between
`llvm.wasm.rethrow.in.catch` and the real wasm `rethrow` instruction. To
generate a `rethrow` instruction, we need an `except_ref` argument,
which is generated from `catch` instruction. But `catch` instrutions are
added in LateEHPrepare pass, so we use `RETHROW_IN_CATCH`, which takes
no argument, until we are able to correctly lower it to `rethrow` in
LateEHPrepare.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59352
llvm-svn: 356316
Summary:
Currently the order of these methods does not matter, but the following
CL needs to have this order changed. Merging the order change and the
semantics change within a CL complicates the diff, so submitting the
order change first.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59342
llvm-svn: 356315
Summary:
Rewrite WebAssemblyFixIrreducibleControlFlow to a simpler and cleaner
design, which directly computes reachability and other properties
itself. This avoids previous complexity and bugs. (The new graph
analyses are very similar to how the Relooper algorithm would find loop
entries and so forth.)
This fixes a few bugs, including where we had a false positive and
thought fannkuch was irreducible when it was not, which made us much
larger and slower there, and a reverse bug where we missed
irreducibility. On fannkuch, we used to be 44% slower than asm2wasm and
are now 4% faster.
Reviewers: aheejin
Subscribers: jdoerfert, mgrang, dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D58919
Patch by Alon Zakai (kripken)
llvm-svn: 356313
Summary:
After instruction selection phase, possibly-throwing calls, which were
previously invoke, are wrapped in `EH_LABEL` instructions. For example:
```
EH_LABEL <mcsymbol .Ltmp0>
CALL_VOID @foo ...
EH_LABEL <mcsymbol .Ltmp1>
```
`EH_LABEL` is placed also in the beginning of EH pads:
```
bb.1 (landing-pad):
EH_LABEL <mcsymbol .Ltmp2>
...
```
And we'd like to maintian this relationship, so when we place a `try`,
```
TRY ...
EH_LABEL <mcsymbol .Ltmp0>
CALL_VOID @foo ...
EH_LABEL <mcsymbol .Ltmp1>
```
When we place a `catch`,
```
bb.1 (landing-pad):
EH_LABEL <mcsymbol .Ltmp2>
%0:except_ref = CATCH ...
...
```
Previously we didn't treat EH_LABELs specially, so `try` was placed
right before a call, and `catch` was placed in the beginning of an EH
pad.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58914
llvm-svn: 355996
Summary:
Uses the named operands tablegen feature to look up the indices of
offset, address, and p2align operands for all load and store
instructions. This replaces brittle, incorrect logic for identifying
loads and store when eliminating frame indices, which previously
crashed on bulk-memory ops. It also cleans up the SetP2Alignment pass.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59007
llvm-svn: 355770
Summary:
- Replaces some uses of `MachineFunction::iterator(MBB)` with
`MBB->getIterator()` and `MachineBasicBlock::iterator(MI)` with
`MI->getIterator()`, which are simpler.
- Replaces some uses of `std::prev` of `std::next` that takes a
MachineFunction or MachineBasicBlock iterator with `getPrevNode` and
`getNextNode`, which are also simpler.
Reviewers: sbc100
Subscribers: dschuff, sunfish, jgravelle-google, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58913
llvm-svn: 355444
Summary:
This is quite minimal so far, introduce them with .section,
fill them with .int8 or .asciz, end with .size
Reviewers: dschuff, sbc100, aheejin
Subscribers: jgravelle-google, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58660
llvm-svn: 355321
Summary:
Before when we implemented the first EH proposal, 'catch <tag>'
instruction may not catch an exception so there were multiple EH pads an
exception can unwind to. That means a BB could have multiple EH pad
successors.
Now after we switched to the new proposal, every 'catch' instruction
catches an exception, and there is only one catchpad per catchswitch, so
we at most have one EH pad successor, making `ThrowUnwindDest` map in
`WasmEHInfo` unnecessary.
Keeping `ThrowUnwindDest` map in `WasmEHInfo` has its own problems,
because other optimization passes can split a BB that contains possibly
throwing calls (previously invokes), and we have to update the map every
time that happens, which is not easy for common CodeGen passes.
This also correctly updates successor info in LateEHPrepare when we add
a rethrow instruction.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58486
llvm-svn: 355296
Summary:
This prevents crashes in instruction selection when these operations
are used. The tests check that the scalar version of the instruction
is used where applicable, although some expansions do not use the
scalar version.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58859
llvm-svn: 355261
Summary:
In the clang UI, replaces -mthread-model posix with -matomics as the
source of truth on threading. In the backend, replaces
-thread-model=posix with the atomics target feature, which is now
collected on the WebAssemblyTargetMachine along with all other used
features. These collected features will also be used to emit the
target features section in the future.
The default configuration for the backend is thread-model=posix and no
atomics, which was previously an invalid configuration. This change
makes the default valid because the thread model is ignored.
A side effect of this change is that objects are never emitted with
passive segments. It will instead be up to the linker to decide
whether sections should be active or passive based on whether atomics
are used in the final link.
Reviewers: aheejin, sbc100, dschuff
Subscribers: mehdi_amini, jgravelle-google, hiraditya, sunfish, steven_wu, dexonsmith, rupprecht, jfb, jdoerfert, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D58742
llvm-svn: 355112
Summary:
When creating `ScopeTops` info for `try` ~ `catch` ~ `end_try`, we
should create not only `end_try` -> `try` mapping but also `catch` ->
`try` mapping as well. If this is not created, `block` and `end_block`
markers later added may span across an existing `catch`, resulting in
the incorrect code like:
```
try
block --| (X)
catch |
end_block --|
end_try
```
Reviewers: dschuff
Subscribers: sunfish, sbc100, jgravelle-google, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58605
llvm-svn: 354945
Summary:
This removes unnecessary instructions after TRY marker placement. There
are two cases:
- `end`/`end_block` can be removed if they overlap with `try`/`end_try`
and they have the same return types.
- `br` right before `catch` that branches to after `end_try` can be
deleted.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58591
llvm-svn: 354939
For outgoing varargs arguments, it's necessary to check the OrigAlign field
of the corresponding OutputArg entry to determine argument alignment, rather
than just computing an alignment from the argument value type. This is
because types like fp128 are split into multiple argument values, with
narrower types that don't reflect the ABI alignment of the full fp128.
This fixes the printf("printfL: %4.*Lf\n", 2, lval); testcase.
Differential Revision: https://reviews.llvm.org/D58656
llvm-svn: 354846
Summary: We shouldn't delete elements while iterating a ranged for loop.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58519
llvm-svn: 354844
Fixes https://bugs.llvm.org/show_bug.cgi?id=40805 introduced by
patterns added in D53676.
I'm removing the patterns entirely here, as they are not correct
in the general case. If necessary something more specific can be
added in the future.
Differential Revision: https://reviews.llvm.org/D58575
llvm-svn: 354733
We record the type of the symbol (event/function/data/global) in the
MCWasmSymbol and so it should always be clear how to handle a relocation
based on the symbol itself.
The exception is a function which still needs the special @TYPEINDEX
then the relocation contains the signature rather than the address
of the functions.
Differential Revision: https://reviews.llvm.org/D58472
llvm-svn: 354697
Previously if we couldn't derive a prototype for a "no-prototype"
function from C we would leave it as is:
void foo(...)
With this change we instead give is an empty signature and remove
the "no-prototype" attribute.
This fixes the current wasm waterfall test failure.
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58488
llvm-svn: 354544
When we can't determine with certainty the signature of a function
import we pick the fist signature we find rather than error'ing out.
The resulting program might not do what is expected since we might pick
the wrong signature. However since undefined behavior in C to use the
same function with different signatures this seems better than refusing
to compile such programs.
Fixes PR40472
Differential Revision: https://reviews.llvm.org/D58304
llvm-svn: 354523
Summary:
- Make `ATOMIC_I`, `ATOMIC_NRI`, `AtomicLoad`, `AtomicStore` classes and
make other operations inherit from them
- Factor the common opcode prefix '0xfe' out from the opcodes into the
common class
- Reorder instructions in the order of increasing opcodes
Reviewers: tlively
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58338
llvm-svn: 354421
Summary:
Fixed a bug in the routine in AsmParser that determines whether the
current instruction is a load or a store. Atomic instructions' prefixes
are not `atomic_` but `atomic.`, and all atomic instructions are also
memory instructions. Also fixed the printing format of atomic
instructions to match other memory instructions and added encoding tests
for atomic instructions.
Reviewers: aardappel, tlively
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58337
llvm-svn: 354419
Summary:
Rename MemoryIndex to InitFlags and implement logic for determining
data segment layout in ObjectYAML and MC. Also adds a "passive" flag
for the .section assembler directive although this cannot be assembled
yet because the assembler does not support data sections.
Reviewers: sbc100, aardappel, aheejin, dschuff
Subscribers: jgravelle-google, hiraditya, sunfish, rupprecht, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57938
llvm-svn: 354397
Summary:
There are a few instructions that all map to the same opcode, so
when disassembling, we have to pick one. That was just the first one
before (the except_ref variant in the case of "call"), now it is the
one marked as IsCanonical in tablegen, or failing that, the shortest
name (which is typically the "canonical" one).
Also introduced a canonical "end" instruction for this purpose.
Reviewers: dschuff, tlively
Subscribers: sbc100, jgravelle-google, aheejin, llvm-commits, sunfish
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57713
llvm-svn: 353131
I'm looking at adding a second INLINEASM opcode for better modeling asm-goto
as a terminator. Using the existing predicate will reduce teh number of
places that will need to use the new opcode.
llvm-svn: 353095
Summary:
This patch fixes clang-tidy warnings on wasm-only files.
The list of checks used is:
`-*,clang-diagnostic-*,llvm-*,misc-*,-misc-unused-parameters,readability-identifier-naming,modernize-*`
(LLVM's default .clang-tidy list is the same except it does not have
`modernize-*`. But I've seen in multiple CLs in LLVM the modernize style
was recommended and code was fixed based on the style, so I added it as
well.)
The common fixes are:
- Variable names start with an uppercase letter
- Function names start with a lowercase letter
- Use `auto` when you use casts so the type is evident
- Use inline initialization for class member variables
- Use `= default` for empty constructors / destructors
- Use `using` in place of `typedef`
Reviewers: sbc100, tlively, aardappel
Subscribers: dschuff, sunfish, jgravelle-google, yurydelendik, kripken, MatzeB, mgorny, rupprecht, llvm-commits
Differential Revision: https://reviews.llvm.org/D57500
llvm-svn: 353075
Summary:
These were "boilerplate" that repeated information already present
in .functype and end_function, that needed to be repeated to Please
the particular way our object writing works, and missing them would
generate errors.
Instead, we generate the information for these automatically so the
user can concern itself with writing more canonical wasm functions
that always work as expected.
Reviewers: dschuff, sbc100
Subscribers: jgravelle-google, aheejin, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D57546
llvm-svn: 353067
See https://github.com/WebAssembly/tool-conventions/pull/95.
This is less typing and IMHO more readable, and it also fits with
our naming around the binary format which tends to use the short name.
e.g.
include/llvm/BinaryFormat/Wasm.h
tools/llvm-objdump/WasmDump.cpp
etc..
Differential Revision: https://reviews.llvm.org/D57611
llvm-svn: 353062
This cleans up all LoadInst creation in LLVM to explicitly pass the
value type rather than deriving it from the pointer's element-type.
Differential Revision: https://reviews.llvm.org/D57172
llvm-svn: 352911
This cleans up all CallInst creation in LLVM to explicitly pass a
function type rather than deriving it from the pointer's element-type.
Differential Revision: https://reviews.llvm.org/D57170
llvm-svn: 352909
Recommit r352791 after tweaking DerivedTypes.h slightly, so that gcc
doesn't choke on it, hopefully.
Original Message:
The FunctionCallee type is effectively a {FunctionType*,Value*} pair,
and is a useful convenience to enable code to continue passing the
result of getOrInsertFunction() through to EmitCall, even once pointer
types lose their pointee-type.
Then:
- update the CallInst/InvokeInst instruction creation functions to
take a Callee,
- modify getOrInsertFunction to return FunctionCallee, and
- update all callers appropriately.
One area of particular note is the change to the sanitizer
code. Previously, they had been casting the result of
`getOrInsertFunction` to a `Function*` via
`checkSanitizerInterfaceFunction`, and storing that. That would report
an error if someone had already inserted a function declaraction with
a mismatching signature.
However, in general, LLVM allows for such mismatches, as
`getOrInsertFunction` will automatically insert a bitcast if
needed. As part of this cleanup, cause the sanitizer code to do the
same. (It will call its functions using the expected signature,
however they may have been declared.)
Finally, in a small number of locations, callers of
`getOrInsertFunction` actually were expecting/requiring that a brand
new function was being created. In such cases, I've switched them to
Function::Create instead.
Differential Revision: https://reviews.llvm.org/D57315
llvm-svn: 352827
Summary:
The custom lowering introduced in rL352592 creates build_vector nodes
with negative i32 operands, but these operands did not meet the value
range constraints necessary to match build_vector nodes. This CL fixes
the issue by removing the unnecessary constraints.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish
Differential Revision: https://reviews.llvm.org/D57481
llvm-svn: 352813
This reverts commit f47d6b38c7 (r352791).
Seems to run into compilation failures with GCC (but not clang, where
I tested it). Reverting while I investigate.
llvm-svn: 352800
The FunctionCallee type is effectively a {FunctionType*,Value*} pair,
and is a useful convenience to enable code to continue passing the
result of getOrInsertFunction() through to EmitCall, even once pointer
types lose their pointee-type.
Then:
- update the CallInst/InvokeInst instruction creation functions to
take a Callee,
- modify getOrInsertFunction to return FunctionCallee, and
- update all callers appropriately.
One area of particular note is the change to the sanitizer
code. Previously, they had been casting the result of
`getOrInsertFunction` to a `Function*` via
`checkSanitizerInterfaceFunction`, and storing that. That would report
an error if someone had already inserted a function declaraction with
a mismatching signature.
However, in general, LLVM allows for such mismatches, as
`getOrInsertFunction` will automatically insert a bitcast if
needed. As part of this cleanup, cause the sanitizer code to do the
same. (It will call its functions using the expected signature,
however they may have been declared.)
Finally, in a small number of locations, callers of
`getOrInsertFunction` actually were expecting/requiring that a brand
new function was being created. In such cases, I've switched them to
Function::Create instead.
Differential Revision: https://reviews.llvm.org/D57315
llvm-svn: 352791
Summary:
After the staack is unwound due to a thrown exxception,
`__stack_pointer` global can point to an invalid address. So
a `global.set` to restore `__stack_pointer` should be inserted right
after `catch` instruction.
But after r352598 the `global.set` instruction is inserted not right
after `catch` but after `block` - `br-on-exn` - `end_block` -
`extract_exception` sequence. This CL fixes it.
While doing that, we can actually move ReplacePhysRegs pass after
LateEHPrepare and merge EHRestoreStackPointer pass into LateEHPrepare,
and now placing `global.set` to `__stack_pointer` right after `catch` is
much easier. Otherwise it is hard to guarantee that `global.set` is
still right after `catch` and not touched with other transformations, in
which case we have to do something to hoist it.
Reviewers: dschuff
Subscribers: mgorny, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D57421
llvm-svn: 352681
Summary:
This switches the EH implementation to the new proposal:
https://github.com/WebAssembly/exception-handling/blob/master/proposals/Exceptions.md
(The previous proposal was
https://github.com/WebAssembly/exception-handling/blob/master/proposals/old/Exceptions.md)
- Instruction changes
- Now we have one single `catch` instruction that returns a except_ref
value
- `throw` now can take variable number of operations
- `rethrow` does not have 'depth' argument anymore
- `br_on_exn` queries an except_ref to see if it matches the tag and
branches to the given label if true.
- `extract_exception` is a pseudo instruction that simulates popping
values from wasm stack. This is to make `br_on_exn`, a very special
instruction, work: `br_on_exn` puts values onto the stack only if it
is taken, and the # of values can vay depending on the tag.
- Now there's only one `catch` per `try`, this patch removes all special
handling for terminate pad with a call to `__clang_call_terminate`.
Before it was the only case there are two catch clauses (a normal
`catch` and `catch_all` per `try`).
- Make `rethrow` act as a terminator like `throw`. This splits BB after
`rethrow` in WasmEHPrepare, and deletes an unnecessary `unreachable`
after `rethrow` in LateEHPrepare.
- Now we stop at all catchpads (because we add wasm `catch` instruction
that catches all exceptions), this creates new
`findWasmUnwindDestinations` function in SelectionDAGBuilder.
- Now we use `br_on_exn` instrution to figure out if an except_ref
matches the current tag or not, LateEHPrepare generates this sequence
for catch pads:
```
catch
block i32
br_on_exn $__cpp_exception
end_block
extract_exception
```
- Branch analysis for `br_on_exn` in WebAssemblyInstrInfo
- Other various misc. changes to switch to the new proposal.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D57134
llvm-svn: 352598
Summary:
Implements custom lowering logic that finds the optimal value for the
initial splat of the vector and either uses it or uses v128.const if
it is available and if it would produce smaller code. This logic
replaces large TableGen ISEL patterns that would lower all non-splat
BUILD_VECTORs into a splat followed by a fixed number of replace_lane
instructions. This CL fixes PR39685.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56633
llvm-svn: 352592
Re-enable the code to rewrite main-function signatures into
"int main(int argc, char *argv[])", but limited to only handling
the case of "int main(void)", so that it doesn't silently strip
an argument in the "int main(int argc, char *argv[], char *envp[])"
case.
This allows main to be called by C startup code, since WebAssembly
requires caller and callee signatures to match, so it can't rely
on passing main a different number of arguments than it expects.
Differential Revision: https://reviews.llvm.org/D57323
llvm-svn: 352479
Previously we were only handling bitcast operations, however
prototypeless functions can also appear in other places such as
comparisons and as function params.
Switch to using replaceAllUsesWith() to replace the prototype-less
function uses. This new approach results in some redundant bitcasting
but is much simpler and handles all cases.
Differential Revision: https://reviews.llvm.org/D56938
llvm-svn: 352445
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Summary:
objdump was interpreting the function header containing the locals
declaration as instructions. To parse these without injecting target
specific code in objdump, MCDisassembler::onSymbolStart was added to
be implemented by the WebAssembly implemention.
WasmObjectFile now returns a code offset for the "address" of a symbol,
rather than the index. This is also more in-line with what other
targets do.
Also ensured that the AsmParser correctly puts each function
in its own segment to enable this test case.
Reviewers: sbc100, dschuff
Subscribers: jgravelle-google, aheejin, sunfish, rupprecht, llvm-commits
Differential Revision: https://reviews.llvm.org/D56684
llvm-svn: 351460
Summary:
Everything before the word "version" is the tool, and everything after
the word "version" is the version.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56742
llvm-svn: 351399
Summary:
As described in PR40209, there can be issues in DBG_VALUEs handling when multiple defs present in a BB. This patch
adds logic for detection of related to def DBG_VALUEs and localizes register update and movement to found DBG_VALUEs.
Reviewers: aheejin
Subscribers: mgorny, dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56401
llvm-svn: 351216
Summary:
V8 currently implements SIMD shifts as taking an immediate operation,
which disagrees with the spec proposal and the toolchain
implementation. As a stopgap measure to get things working, unroll all
vector shifts. Since this is a temporary measure, there are no tests.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, dmgreen, llvm-commits
Differential Revision: https://reviews.llvm.org/D56520
llvm-svn: 351151
This removes the old grow_memory and mem.grow-style intrinsics, leaving just
the memory.grow-style intrinsics.
Differential Revision: https://reviews.llvm.org/D56645
llvm-svn: 351084
Summary:
We now use __stack_pointer global and global.get/global.set instruction.
This fixes the checking routine for stack_pointer writes accordingly.
This also fixes the existing __stack_pointer test in reg-stackify.ll:
That test used to pass not because of __stack_pointer clashes but
because the function `stackpointer_callee` was not marked as `readnone`,
so it was assumed to possibly write to memory arbitraily, and
`global.set` instruction was marked as `mayStore` in the .td definition,
so they were identified as intervening writes. After we added `readnone`
to its attribute, this test fails without this patch.
Reviewers: dschuff, sunfish
Subscribers: jgravelle-google, sbc100, llvm-commits
Differential Revision: https://reviews.llvm.org/D56094
llvm-svn: 350906
Summary:
This is a third attempt, but this time we have vetted it on Windows
first. The previous errors were due to an uninitialized class member.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D56560
llvm-svn: 350901
This is a second attempt at r350778, which was reverted in
r350789. The only change is that the unimplemented-simd128 feature has
been renamed simd128-unimplemented, since naming it
unimplemented-simd128 somehow made the simd128 feature flag enable the
unimplemented-simd128 feature on Windows.
llvm-svn: 350791
Summary:
This replaces the old ad-hoc -wasm-enable-unimplemented-simd
flag. Also makes the new unimplemented-simd128 feature imply the
simd128 feature.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits, alexcrichton
Differential Revision: https://reviews.llvm.org/D56501
llvm-svn: 350778
Summary:
Looks like many passes print its pass description as a debug message at
the start of each pass, so added that to (mostly newly added) other
passes as well.
Reviewers: dschuff
Subscribers: jgravelle-google, sbc100, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56142
llvm-svn: 350771
Summary:
For some reason the backend assumed that the condition mask would be
the first argument to the LLVM intrinsic, but everywhere else the
condition mask is the third argument.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56412
llvm-svn: 350746
Summary:
StoreResults pass does not optimize store instructions anymore because
store instructions don't return results values anymore. Now this pass is
used solely for memory intrinsics, so update the pass name accordingly
and fix outdated pass descriptions as well.
This patch does not change any meaningful behavior, but not marked as
NFC because it changes a comment check line in a test case.
Reviewers: dschuff
Subscribers: mgorny, sbc100, jgravelle-google, sunfiish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56093
llvm-svn: 350669
Summary:
FixIrreducibleControlFlow and LateEHPrepare both possibly modify CFG and
create new registers. There seems to be no reason these passes go after
register-related optimization passes (PrepareForLiveIntervals,
OptimizeLiveIntervals, StoreResults, RegStackify, and RegColoring), and
this also possibly create new optimization opportunities. I think we
should put all current and future optimization passes before RegStackify
(and related passes) unless there's a reason not to.
Reviewers: kripken
Subscribers: dschuff, sbc100, sunfish, jgravelle-google, llvm-commits
Differential Revision: https://reviews.llvm.org/D56356
llvm-svn: 350596
Summary:
We don't need to explicitly use `NI` anymore because we now don't use
`let` statements within the definitions.
Reviewers: aardappel
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56376
llvm-svn: 350594
Move the check for -1 and identical values outside the vector sorting code.
Compare functions need to be able to compare identical elements to be
conforming.
llvm-svn: 350379
Summary:
Irreducible control flow is not that rare, e.g. it happens in malloc and
3 other places in the libc portions linked in to a hello world program.
This patch improves how we handle that code: it emits a br_table to
dispatch to only the minimal necessary number of blocks. This reduces
the size of malloc by 33%, and makes it comparable in size to asm2wasm's
malloc output.
Added some tests, and verified this passes the emscripten-wasm tests run
on the waterfall (binaryen2, wasmobj2, other).
Reviewers: aheejin, sunfish
Subscribers: mgrang, jgravelle-google, sbc100, dschuff, llvm-commits
Differential Revision: https://reviews.llvm.org/D55467
Patch by Alon Zakai (kripken)
llvm-svn: 350367
Summary:
The previously introduced new operand type for br_table didn't have
a disassembler implementation, causing an assert.
Reviewers: dschuff, aheejin
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56227
llvm-svn: 350366
Summary:
Instead of asserting on certain kinds of malformed instructions, it
now still print, but instead adds an annotation indicating the
problem, and/or indicates invalid_type etc.
We're using the InstPrinter from many contexts that can't always
guarantee values are within range (e.g. the disassembler), where having
output is more valueable than asserting.
Reviewers: dschuff, aheejin
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56223
llvm-svn: 350365
Summary:
This was previously ignored and an incorrect value generated.
Also fixed Disassembler's handling of block_type.
Reviewers: dschuff, aheejin
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56092
llvm-svn: 350270
Summary:
These instructions are currently unused in our backend, but for
completeness it is good to support them, so they can be used with
the assembler in hand-written code.
Tests are very basic, signature support missing much like other blocks.
Reviewers: dschuff, aheejin
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55973
llvm-svn: 350079
Summary:
It does so using a simple nesting stack, and gives clear errors upon
violation. This is unique to wasm, since most CPUs do not have
any nested constructs.
Had to add an end of file check to the general assembler for this.
Note: if/else/end instructions are not currently supported in our
tablegen defs, so these tests will be enabled in a follow-up.
They already pass the nesting check.
Reviewers: dschuff, aheejin
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55797
llvm-svn: 350078
Summary:
This is a code size savings and is also important to get runnable code
while engines do not support v128.const.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55910
llvm-svn: 349724
Summary:
Gates v128.const, f32x4.sqrt, f32x4.div, i8x16.extract_lane_u, and
i16x8.extract_lane_u on the --wasm-enable-unimplemented-simd flag,
since these ops are not implemented yet in V8.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55904
llvm-svn: 349720
Summary:
We use `variable_ops` in the tablegen defs to denote the list of
branch targets in `br_table`, but unlike other uses of `variable_ops`
(e.g. call) the these branch targets need to actually be encoded in the
instruction. The existing tables for `variable_ops` cause not operands
to be accepted by the assembly matcher.
Following the example of ARM:
2cc0a7da87/lib/Target/ARM/ARMInstrInfo.td (L550-L555)
we introduce a new operand type to capture this list, and we use the
same {} syntax as ARM as well to differentiate them from regular
integer operands.
Also removed definition and use of TSFlags in tablegen defs, since
`br_table` now has a non-variable_ops immediate operand, so the
previous logic of only the variable_ops arguments being labels didn't
make sense anymore.
Reviewers: dschuff, aheejin, sunfish
Subscribers: javed.absar, sbc100, jgravelle-google, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D55401
llvm-svn: 349405
Summary:
This patch supports `.eventtype` directive printing and parsing in the
same syntax with `.functype`.
Reviewers: aardappel, sbc100
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55353
llvm-svn: 348818
Summary:
- Unify mixed argument names (`Symbol` and `Sym`) to `Sym`
- Changed `MCSymbolWasm*` argument of `emit***` functions to `const
MCSymbolWasm*`. It seems not very intuitive that emit function in the
streamer modifies symbol contents.
- Moved empty function bodies to the header
- clang-format
Reviewers: aardappel, dschuff, sbc100
Subscribers: jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55347
llvm-svn: 348816
Summary:
- LLVM clang-format style doesn't allow one-line ifs.
- LLVM clang-tidy style says method names should start with a lowercase
letter. But currently WebAssemblyAsmParser's parent class
MCTargetAsmParser is mixing lowercase and uppercase method names
itself so overridden methods cannot be renamed now.
- Changed else ifs after returns to ifs.
- Added some newlines for readability.
Reviewers: aardappel, sbc100
Subscribers: dschuff, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55350
llvm-svn: 348648
Adds fatal errors for any target that does not support the Tiny or Kernel
codemodels by rejigging the getEffectiveCodeModel calls.
Differential Revision: https://reviews.llvm.org/D50141
llvm-svn: 348585
Summary:
The assembler processes directives and instructions in whatever order
they are in the file, then directly emits them to the streamer. This
could cause badly written (or generated) .s files to produce
incorrect binaries.
It now has state that tracks what it has most recently seen, to
enforce they are emitted in a given order that always produces
correct wasm binaries.
Also added a new test that compares obj2yaml output from llc (the
backend) to that going via .s and the assembler to ensure both paths
generate the same binaries.
The features this test covers could be extended.
Passes all wasm Lit tests.
Fixes: https://bugs.llvm.org/show_bug.cgi?id=39557
Reviewers: sbc100, dschuff, aheejin
Subscribers: jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55149
llvm-svn: 348185