The access function has a short entry and a short exit, the initialization
block is only run the first time. To improve the performance, we want to
have a short frame at the entry and exit.
We explicitly handle most of the CSRs via copies. Only the CSRs that are not
handled via copies will be in CSR_SaveList.
Frame lowering and prologue/epilogue insertion will generate a short frame
in the entry and exit according to CSR_SaveList. The majority of the CSRs will
be handled by register allcoator. Register allocator will try to spill and
reload them in the initialization block.
We add CSRsViaCopy, it will be explicitly handled during lowering.
1> we first set FunctionLoweringInfo->SplitCSR if conditions are met (the target
supports it for the given machine function and the function has only return
exits). We also call TLI->initializeSplitCSR to perform initialization.
2> we call TLI->insertCopiesSplitCSR to insert copies from CSRsViaCopy to
virtual registers at beginning of the entry block and copies from virtual
registers to CSRsViaCopy at beginning of the exit blocks.
3> we also need to make sure the explicit copies will not be eliminated.
The target independent portion was committed as r255353.
rdar://problem/23557469
Differential Revision: http://reviews.llvm.org/D15341
llvm-svn: 255821
When comparing a zero-extended value against a constant small enough to
be in range of the inner type, it doesn't matter whether a signed or
unsigned compare operation (for the outer type) is being used. This is
why the code in adjustSubwordCmp had this assertion:
assert(C.ICmpType == SystemZICMP::Any &&
"Signedness shouldn't matter here.");
assuming the the caller had already detected that fact. However, it
turns out that there cases, in particular with always-true or always-
false conditions that have not been eliminated when compiling at -O0,
where this is not true.
Instead of failing an assertion if C.ICmpType is not SystemZICMP::Any
here, we can simply *set* it safely to SystemZICMP::Any, however.
llvm-svn: 255786
This removes an unpleasant hack involving a global variable for special
lowering of certain memcpy calls. These are now lowered as intended in
EmitTargetCodeForMemcpy in the same way that other targets do it.
llvm-svn: 255785
This folds (ashr (shl a, [56,48,32,24,16]), SarConst)
into (shl, (sext (a), [56,48,32,24,16] - SarConst))
or into (lshr, (sext (a), SarConst - [56,48,32,24,16]))
depending on sign of (SarConst - [56,48,32,24,16])
sexts in X86 are MOVs.
The MOVs have the same code size as above SHIFTs (only SHIFT by 1 has lower code size).
However the MOVs have 2 advantages to SHIFTs on x86:
1. MOVs can write to a register that differs from source.
2. MOVs accept memory operands.
This fixes PR24373.
Patch by: evgeny.v.stupachenko@intel.com
Differential Revision: http://reviews.llvm.org/D13161
llvm-svn: 255761
Summary: This patch adds a check in visitLandingPad to see if landingpad's result type is token type. If so, do not create DAG nodes for its exception pointer and selector value. This patch enables the back end to handle landingpads of token type.
Reviewers: JosephTremoulet, majnemer, rnk
Subscribers: sanjoy, llvm-commits
Differential Revision: http://reviews.llvm.org/D15405
llvm-svn: 255749
This patch allows atomic loads and stores of floating point to be specified in the IR and adds an adapter to allow them to be lowered via existing backend support for bitcast-to-equivalent-integer idiom.
Previously, the only way to specify a atomic float operation was to bitcast the pointer to a i32, load the value as an i32, then bitcast to a float. At it's most basic, this patch simply moves this expansion step to the point we start lowering to the backend.
This patch does not add canonicalization rules to convert the bitcast idioms to the appropriate atomic loads. I plan to do that in the future, but for now, let's simply add the support. I'd like to get instruction selection working through at least one backend (x86-64) without the bitcast conversion before canonicalizing into this form.
Similarly, I haven't yet added the target hooks to opt out of the lowering step I added to AtomicExpand. I figured it would more sense to add those once at least one backend (x86) was ready to actually opt out.
As you can see from the included tests, the generated code quality is not great. I plan on submitting some patches to fix this, but help from others along that line would be very welcome. I'm not super familiar with the backend and my ramp up time may be material.
Differential Revision: http://reviews.llvm.org/D15471
llvm-svn: 255737
It adjusts from RSP-after-prologue to RBP, which is what SEH filters
need to do before they can use llvm.localrecover.
Fixes SEH filter captures, which were broken in r250088.
Issue reported by Alex Crichton.
llvm-svn: 255707
This patch improves on the suggested codegen from PR24475:
https://llvm.org/bugs/show_bug.cgi?id=24475
but only for the fmaxf() case to start, so we can sort out any bugs before
extending to fmin, f64, and vectors.
The fmax / maxnum definitions provide us flexibility for signed zeros, so the
only thing we have to worry about in this replacement sequence is NaN handling.
Note 1: It may be better to implement this as lowerFMAXNUM(), but that exposes
a problem: SelectionDAGBuilder::visitSelect() transforms compare/select
instructions into FMAXNUM nodes if we declare FMAXNUM legal or custom. Perhaps
that should be checking for NaN inputs or global unsafe-math before transforming?
As it stands, that bypasses a big set of optimizations that the x86 backend
already has in PerformSELECTCombine().
Note 2: The v2f32 test reveals another bug; the vector is extended to v4f32, so
we have completely unnecessary operations happening on undef elements of the
vector.
Differential Revision: http://reviews.llvm.org/D15294
llvm-svn: 255700
Summary: I'm not sure how things worked before without this.
Reviewers: arsenm
Subscribers: arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D15492
llvm-svn: 255692
Add instruction patterns for matching load and store instructions with constant
offsets in addresses. The code is fairly redundant due to the need to replicate
everything between imm, tglobaldadr, and texternalsym, but this appears to be
common tablegen practice. The main alternative appears to be to introduce
matching functions with C++ code, but sticking with purely generated matchers
seems better for now.
Also note that this doesn't yet support offsets from getelementptr, which will
be the most common case; that will depend on a change in target-independent code
in order to set the NoUnsignedWrap flag, which I'll submit separately. Until
then, the testcase uses ptrtoint+add+inttoptr with a nuw on the add.
Also implement isLegalAddressingMode with an approximation of this.
Differential Revision: http://reviews.llvm.org/D15538
llvm-svn: 255681
SimplifyCFG allows tail merging with code which terminates in
unreachable which, in turn, makes it possible for an invoke to end up in
a funclet which it was not originally part of.
Using operand bundles on invokes allows us to determine whether or not
an invoke was part of a funclet in the source program.
Furthermore, it allows us to unambiguously answer questions about the
legality of inlining into call sites which the personality may have
trouble with.
Differential Revision: http://reviews.llvm.org/D15517
llvm-svn: 255674
Summary:
We were previously selecting all constant loads to SMRD instructions and legalizing
the SMRDs with non-uniform addresses during the SIFixSGPRCopesPass.
This new solution is more simple and also generates much better code, because
the instruction selector is able to take advantage of all the MUBUF addressing
modes that are legalization pass wasn't able to.
We also no longer need to generate v_add_* instructions when we
have a uniform pointer and a non-uniform offset, as this is now folded into the
MUBUF instruction during instruction selection.
Reviewers: arsenm
Subscribers: arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D15425
llvm-svn: 255672
On SparcV8, doubles get passed in two 32-bit integer registers. The call
code was already handling endianness correctly, but the incoming
argument code was not -- it got the two halves in opposite order.
Also remove some dead code in LowerFormalArguments_32 to handle
less-than-32bit values, which can't actually happen.
Finally, add some test cases for the 32-bit calling convention, cribbed
from the 64abi.ll test, and run for both big and little-endian.
llvm-svn: 255668
We only want to emit CFI adjustments when actually using DWARF.
This fixes PR25828.
Differential Revision: http://reviews.llvm.org/D15522
llvm-svn: 255664
"movl $-1, %eax" is 5 bytes, "xorl %eax, %eax; decl %eax" is 3 bytes.
This commit makes LLVM use the latter when optimizing for size.
Differential Revision: http://reviews.llvm.org/D14971
llvm-svn: 255656
Summary:
These are meant to be used instead of the llvm.SI.tid intrinsic which will
be deprecated at some point.
Reviewers: arsenm
Subscribers: arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D15475
llvm-svn: 255652
Summary:
These are meant to be used instead of the llvm.SI.fs.interp intrinsic which
will be deprecated at some point.
Reviewers: arsenm
Subscribers: arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D15474
llvm-svn: 255651
It appears that neither compiler-rt nor the gnu soft-float libraries actually
implement these conversions. Instead of emitting calls to library functions
that don't exist, handle it similarly to the way we handle i8 -> float and
i16 -> float conversions: call the i32 library function, and adjust the type.
Differential Revision: http://reviews.llvm.org/D15151
llvm-svn: 255643
This patch improves a temporary fix in r255530 so that we can normalize
successor list without trigger assertion failures in tail duplication pass.
llvm-svn: 255638
Full type legalizer that works with all vectors length - from 2 to 16, (i32, i64, float, double).
This intrinsic, for example
void @llvm.masked.scatter.v2f32(<2 x float>%data , <2 x float*>%ptrs , i32 align , <2 x i1>%mask )
requires type widening for data and type promotion for mask.
Differential Revision: http://reviews.llvm.org/D13633
llvm-svn: 255629
The post-dominance property is not sufficient to guarantee that a restore point
inside a loop is safe.
E.g.,
while(1) {
Save
Restore
if (...)
break;
use/def CSRs
}
All the uses/defs of CSRs are dominated by Save and post-dominated
by Restore. However, the CSRs uses are still reachable after
Restore and before Save are executed.
This fixes PR25824
llvm-svn: 255613
This case was tested in the linker from code, but not from globals indexing into other globals. The linker currently barfs on this, ncbray volunteered to fix it.
llvm-svn: 255601
Add return type information to call and call_indirect instructions. This
allows them to be disambiguated without knowledge of the callee.
Differential Revision: http://reviews.llvm.org/D15484
llvm-svn: 255565
Implement a new BLOCK scope placement algorithm which better handles
early-return blocks and early exists from nested scopes.
Differential Revision: http://reviews.llvm.org/D15368
llvm-svn: 255564
Part 1 was submitted in http://reviews.llvm.org/D15134.
Changes in this part:
* X86RegisterInfo.td, X86RecognizableInstr.cpp: Add FR128 register class.
* X86CallingConv.td: Pass f128 values in XMM registers or on stack.
* X86InstrCompiler.td, X86InstrInfo.td, X86InstrSSE.td:
Add instruction selection patterns for f128.
* X86ISelLowering.cpp:
When target has MMX registers, configure MVT::f128 in FR128RegClass,
with TypeSoftenFloat action, and custom actions for some opcodes.
Add missed cases of MVT::f128 in places that handle f32, f64, or vector types.
Add TODO comment to support f128 type in inline assembly code.
* SelectionDAGBuilder.cpp:
Fix infinite loop when f128 type can have
VT == TLI.getTypeToTransformTo(Ctx, VT).
* Add unit tests for x86-64 fp128 type.
Differential Revision: http://reviews.llvm.org/D11438
llvm-svn: 255558
It turns out that terminatepad gives little benefit over a cleanuppad
which calls the termination function. This is not sufficient to
implement fully generic filters but MSVC doesn't support them which
makes terminatepad a little over-designed.
Depends on D15478.
Differential Revision: http://reviews.llvm.org/D15479
llvm-svn: 255522
When FastISel fails to translate an instruction it hands off code
generation to SelectionDAG. Before it does so, it may have generated
local value instructions to feed phi nodes in successor blocks. These
instructions will then be generated again by SelectionDAG, causing
duplication and less efficient code, including extra spill
instructions.
Patch by Wolfgang Pieb!
Differential Revision: http://reviews.llvm.org/D11768
llvm-svn: 255520
This is the second in a set of patches for soft float support for ppc32,
it enables soft float operations.
Patch by Strahinja Petrovic.
Differential Revision: http://reviews.llvm.org/D13700
llvm-svn: 255516
EABI attributes should only be emitted on EABI targets. This prevents the
emission of the optimization goals EABI attribute on Windows ARM.
llvm-svn: 255448
Summary:
Previously SelectionDAGBuilder asserted that the pointer operands of
memcpy / memset / memmove intrinsics are in address space < 256. This assert
implicitly assumed the X86 backend, where all address spaces < 256 are
equivalent to address space 0 from the code generator's point of view. On some
targets (R600 and NVPTX) several address spaces < 256 have a target-defined
meaning, so this assert made little sense for these targets.
This patch removes this wrong assertion and adds extra checks before lowering
these intrinsics to library calls. If a pointer operand can't be casted to
address space 0 without changing semantics, a fatal error is reported to the
user.
The new behavior should be valid for all targets that give address spaces != 0
a target-specified meaning (NVPTX, R600, X86). NVPTX lowers big or
variable-sized memory intrinsics before SelectionDAG construction. All other
memory intrinsics are inlined (the threshold is set very high for this target).
R600 doesn't support memcpy / memset / memmove library calls (previously the
illegal emission of a call to such library function triggered an error
somewhere in the code generator). X86 now emits inline loads and stores for
address spaces 256 and 257 up to the same threshold that is used for address
space 0 and reports a fatal error otherwise.
I call this a "partial fix" because there are still cases that can't be
lowered. A fatal error is reported in these cases.
Reviewers: arsenm, theraven, compnerd, hfinkel
Subscribers: hfinkel, llvm-commits, alex
Differential Revision: http://reviews.llvm.org/D7241
llvm-svn: 255441
While we have successfully implemented a funclet-oriented EH scheme on
top of LLVM IR, our scheme has some notable deficiencies:
- catchendpad and cleanupendpad are necessary in the current design
but they are difficult to explain to others, even to seasoned LLVM
experts.
- catchendpad and cleanupendpad are optimization barriers. They cannot
be split and force all potentially throwing call-sites to be invokes.
This has a noticable effect on the quality of our code generation.
- catchpad, while similar in some aspects to invoke, is fairly awkward.
It is unsplittable, starts a funclet, and has control flow to other
funclets.
- The nesting relationship between funclets is currently a property of
control flow edges. Because of this, we are forced to carefully
analyze the flow graph to see if there might potentially exist illegal
nesting among funclets. While we have logic to clone funclets when
they are illegally nested, it would be nicer if we had a
representation which forbade them upfront.
Let's clean this up a bit by doing the following:
- Instead, make catchpad more like cleanuppad and landingpad: no control
flow, just a bunch of simple operands; catchpad would be splittable.
- Introduce catchswitch, a control flow instruction designed to model
the constraints of funclet oriented EH.
- Make funclet scoping explicit by having funclet instructions consume
the token produced by the funclet which contains them.
- Remove catchendpad and cleanupendpad. Their presence can be inferred
implicitly using coloring information.
N.B. The state numbering code for the CLR has been updated but the
veracity of it's output cannot be spoken for. An expert should take a
look to make sure the results are reasonable.
Reviewers: rnk, JosephTremoulet, andrew.w.kaylor
Differential Revision: http://reviews.llvm.org/D15139
llvm-svn: 255422
Summary: This patch adds support of conversion (mul x, 2^N + 1) => (add (shl x, N), x) and (mul x, 2^N - 1) => (sub (shl x, N), x) if the multiplication can not be converted to LEA + SHL or LEA + LEA. LLVM has already supported this on ARM, and it should also be useful on X86. Note the patch currently only applies to cases where the constant operand is positive, and I am planing to add another patch to support negative cases after this.
Reviewers: craig.topper, RKSimon
Subscribers: aemerson, llvm-commits
Differential Revision: http://reviews.llvm.org/D14603
llvm-svn: 255415
This branch adds hints for highly biased branches on the PPC architecture. Even
in absence of profiling information, LLVM will mark code reaching unreachable
terminators and other exceptional control flow constructs as highly unlikely to
be reached.
Patch by Tom Jablin!
llvm-svn: 255398
Eric Christopher