Since an add instruction must produce an unused carry out, this
requires additional SGPRs. This can be avoided by keeping the entire
offset computation in SGPRs. If one SGPR is still available, this only
costs one extra mov. If none are available, the entire computation can
be done in place and reversed.
This does assume the use is a VGPR operand. This was already assumed,
and we currently only select frame indexes to VALU instructions. This
should probably be fixed at some point to handle more possible MIR.
llvm-svn: 370929
For any unpaired muls, we accumulate them as an input to the
reduction. Check the type of the mul and perform a sext if the
existing accumlator input type is not the same.
Differential Revision: https://reviews.llvm.org/D66993
llvm-svn: 370851
This reverts r370525 (git commit 0bb1630685)
Also reverts r370543 (git commit 185ddc08ee)
The approach I took only works for functions marked `noreturn`. In
general, a call that is not known to be noreturn may be followed by
unreachable for other reasons. For example, there could be multiple call
sites to a function that throws sometimes, and at some call sites, it is
known to always throw, so it is followed by unreachable. We need to
insert an `int3` in these cases to pacify the Windows unwinder.
I think this probably deserves its own standalone, Win64-only fixup pass
that runs after block placement. Implementing that will take some time,
so let's revert to TrapUnreachable in the mean time.
llvm-svn: 370829
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
Now that we have the infrastructure to support s128 types as parameters
we can expand these to libcalls.
Differential Revision: https://reviews.llvm.org/D66185
llvm-svn: 370823
On AArch64, s128 types have to be split into s64 GPRs when passed as arguments.
This change adds the generic support in call lowering for dealing with multiple
registers, for incoming and outgoing args.
Support for splitting for return types not yet implemented.
Differential Revision: https://reviews.llvm.org/D66180
llvm-svn: 370822
Summary:
Simplify the right shift of the intermediate result (given
in four parts) by using funnel shift.
There are some impact on lit tests, but that seems to be
related to register allocation differences due to how FSHR
is expanded on X86 (giving a slightly different operand order
for the OR operations compared to the old code).
Reviewers: leonardchan, RKSimon, spatel, lebedev.ri
Reviewed By: RKSimon
Subscribers: hiraditya, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, s.egerton, pzheng, bevinh, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67036
llvm-svn: 370813
This pattern, when imported at -O0 adds an extra copy via the SUBREG_TO_REG.
This is because the SUBREG_TO_REG is not eliminated. At all other opt levels,
it is eliminated.
This is a 1% geomean code size savings at -O0 on CTMark.
Differential Revision: https://reviews.llvm.org/D67027
llvm-svn: 370789
The code here seems to date back to r134705, when tablegen lowering was first
being added. I don't believe that we need to include CPSR implicit operands on
the MCInst. This now works more like other backends (like AArch64), where all
implicit registers are skipped.
This allows the AliasInst for CSEL's to match correctly, as can be seen in the
test changes.
Differential revision: https://reviews.llvm.org/D66703
llvm-svn: 370745
This moves ConstantMaterializationCost into ARMBaseInstrInfo so that it can
also be used in ISel Lowering, adding codesize values to the computed costs, to
be able to compare either approximate instruction counts or codesize costs.
It also adds a HasLowerConstantMaterializationCost, which compares the
ConstantMaterializationCost of two values, returning true if the first is
smaller either in instruction count/codesize, or falling back to the other in
the case that they are equal.
This is used in constant CSEL lowering to invert the predicate if the opposite
is easier to materialise.
Differential revision: https://reviews.llvm.org/D66701
llvm-svn: 370741
Arm 8.1-M adds a number of related CSEL instructions, including CSINC, CSNEG and CSINV. These choose between two values given the content in CPSR and a condition, performing an increment, negation or inverse of the false value.
This adds some selection for them, either from constant values or patterns. It does not include CSEL directly, which is currently not always making code better. It is still useful, but we will have to check more carefully where it should and shouldn't be used.
Code by Ranjeet Singh and Simon Tatham, with some modifications from me.
Differential revision: https://reviews.llvm.org/D66483
llvm-svn: 370739
Now the last `.section` directive in the MIPS asm file preamble
is the `.section .mdebug.abi`. If assembler code injected for example
by the LLVM `module asm` or the C ` __asm` directives do not contain
explicit switching to the `.text` section it goes to the `.mdebug.abi`
section. It might be unexpected to the user and in fact for example
breaks building some existing code like FreeBSD libc [1].
The patch forces switching to the `.text` section after emitting MIPS
assembler file preamble.
[1] https://bugs.llvm.org/show_bug.cgi?id=43119
Fix PR43119.
Differential Revision: https://reviews.llvm.org/D67014
llvm-svn: 370735
We were using isShiftedInt<7, Shift>(RHSC) to detect the ranges of offsets to
fold into MVE loads/stores. The instructions actually take a 7 bit unsigned
integer which is either added or subtracted. So something more like
isShiftedUInt<7, Shift>(abs(RHSC)).
Instead I've changes this to use the isScaledConstantInRange method, same as in
SelectT2AddrModeImm7Offset used by pre/post inc, which seemed to already be
getting this correct.
Differential revision: https://reviews.llvm.org/D66997
llvm-svn: 370731
To save a 'add sp,#val' instruction by adding registers to the final pop instruction,
the first register transferred by this pop instruction need to be found.
If the function to be optimized has a non-void return value, the operand list contains
r0 (implicit) which prevents the optimization to take place.
Therefore implicit register references should be skipped in the search loop,
because this registers are never popped from the stack.
Patch by Rainer Herbertz (rOptimizer)!
Differential revision: https://reviews.llvm.org/D66730
llvm-svn: 370728
Emitting a schedule is really hard. There are lots of corner cases to take care of; in fact, of the 60+ SWP-specific testcases in the Hexagon backend most of those are testing codegen rather than the schedule creation itself.
One issue is that to test an emission corner case we must craft an input such that the generated schedule uses that corner case; sometimes this is very hard and convolutes testcases. Other times it is impossible but we want to test it anyway.
This patch adds a simple test pass that will consume a module containing a loop and generate pipelined code from it. We use post-instr-symbols as a way to annotate instructions with the stage and cycle that we want to schedule them at.
We also provide a flag that causes the MachinePipeliner to generate these annotations instead of actually emitting code; this allows us to generate an input testcase with:
llc < %s -stop-after=pipeliner -pipeliner-annotate-for-testing -o test.mir
And run the emission in isolation with:
llc < test.mir -run-pass=modulo-schedule-test
llvm-svn: 370705
Use Custom lowering instead. Fall back to default expansion only
when the scalar FP type belongs in an XMM register. This improves
lowering for i32 to fp80, and also i32 to double on SSE1 only.
llvm-svn: 370699
FP128 values are passed in xmm registers so should be asssociated
with an SSE feature rather than MMX which uses a different set
of registers.
llc enables sse1 and sse2 by default with x86_64. But does not
enable mmx. Clang enables all 3 features by default.
I've tried to add command lines to test with -sse
where possible, but any test that returns a value in an xmm
register fails with a fatal error with -sse since we have no
defined ABI for that scenario.
llvm-svn: 370682
We should be using MQPR, and if we don't we can get COPYs and PHIs created for
QPR. These get folded into instructions, failing verification checks.
Differential revision: https://reviews.llvm.org/D66214
llvm-svn: 370676
Now that constrained fpto[su]i intrinsic are available,
add codegen support to the SystemZ backend.
In addition to pure back-end changes, I've also needed
to add the strict_fp_to_[su]int and any_fp_to_[su]int
pattern fragments in the obvious way.
llvm-svn: 370674
Summary:
Adds the following inline asm constraints for SVE:
- w: SVE vector register with full range, Z0 to Z31
- x: Restricted to registers Z0 to Z15 inclusive.
- y: Restricted to registers Z0 to Z7 inclusive.
This change also adds the "z" modifier to interpret a register as an SVE register.
Not all of the bitconvert patterns added by this patch are used, but they have been included here for completeness.
Reviewers: t.p.northover, sdesmalen, rovka, momchil.velikov, rengolin, cameron.mcinally, greened
Reviewed By: sdesmalen
Subscribers: javed.absar, tschuett, rkruppe, psnobl, cfe-commits, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66302
llvm-svn: 370673
The motivating bugs are:
https://bugs.llvm.org/show_bug.cgi?id=41340https://bugs.llvm.org/show_bug.cgi?id=42697
As discussed there, we could view this as a failure of IR canonicalization,
but then we would need to implement a backend fixup with target overrides
to get this right in all cases. Instead, we can just view this as a codegen
opportunity. It's not even clear for x86 exactly when we should favor
test+set; some CPUs have better theoretical throughput for the ALU ops than
bt/test.
This patch is made more complicated than I expected because there's an early
DAGCombine for 'and' that can change types of the intermediate ops via
trunc+anyext.
Differential Revision: https://reviews.llvm.org/D66687
llvm-svn: 370668
Summary:
D61491 caused us to use relocs when they're not strictly necessary, to
refer to symbols in the text section. This is a pessimization and it's a
problem for some loaders that don't support relocs yet.
Reviewers: nhaehnle, arsenm, tpr
Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, t-tye, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65813
llvm-svn: 370667
MachineLICM can hoist an invariant load, but if that load is folded it needs to be unfolded. On AVX512 sometimes this load is an broadcast load which we were previously unable to unfold. This patch adds initial support for that with a very basic list of supported instructions as a starting point.
Differential Revision: https://reviews.llvm.org/D67017
llvm-svn: 370620
The motivating case for this is a long way from here:
https://bugs.llvm.org/show_bug.cgi?id=43146
...but I think this is where we have to start.
We need to canonicalize/optimize sequences of shift and logic to ease
pattern matching for things like bswap and improve perf in general.
But without the artificial limit of '!LegalTypes' (early combining),
there are a lot of test diffs, and not all are good.
In the minimal tests added for this proposal, x86 should have better
throughput in all cases. AArch64 is neutral for scalar tests because
it can fold shifts into bitwise logic ops.
There are 3 shift opcodes and 3 logic opcodes for a total of 9 possible patterns:
https://rise4fun.com/Alive/VlIhttps://rise4fun.com/Alive/n1mhttps://rise4fun.com/Alive/1Vn
Differential Revision: https://reviews.llvm.org/D67021
llvm-svn: 370617
These were never enabled correctly and are causing other problems. Taking them
out for the moment, whilst we work on the issues.
This reverts r370329.
llvm-svn: 370607
Summary:
This fixes the bugzilla id 43183 which triggerd by the following commit:
[RISCV] Avoid generating AssertZext for LP64 ABI when lowering floating LibCall
llvm-svn: 370604
There were legalizer asserts in aarch64 globalisel (in debug mode) with s128
sext+icmp before r367060 and r366943 landed. These are just a couple reduced
mir and ir regression tests that came from a build where these were encountered.
llvm-svn: 370602
EltsFromConsecutiveLoads was assuming that the number of input elts was the same as the number of elements in the output vector type when creating a zeroing shuffle, causing an assert when subvectors were being combined instead of just scalars.
llvm-svn: 370592
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
Craig Topper