[SelectionDAG] Add preliminary plumbing for `samesign` flag #112354

antoniofrighetto · 2024-10-15T13:15:22Z

Extend recently-added poison-generating IR flag to codegen as well.

I think there are some other places in TargetLowering (e.g., LegalizeSetCCCondCode) where the flag should be cleared, welcoming directions (also maybe besides SDNodeFlags, it can be added to MIFlag directly here).

llvmbot · 2024-10-15T13:15:56Z

@llvm/pr-subscribers-llvm-globalisel
@llvm/pr-subscribers-backend-aarch64

@llvm/pr-subscribers-llvm-selectiondag

Author: Antonio Frighetto (antoniofrighetto)

Changes

Extend recently-added poison-generating IR flag to codegen as well.

I think there are some other places in TargetLowering (e.g., LegalizeSetCCCondCode) where the flag should be cleared, welcoming directions (also maybe besides SDNodeFlags, it can be added to MIFlag directly here).

Full diff: https://github.com/llvm/llvm-project/pull/112354.diff

4 Files Affected:

(modified) llvm/include/llvm/CodeGen/SelectionDAGNodes.h (+9-5)
(modified) llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp (+4)
(modified) llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp (+3)
(modified) llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp (+7-1)

diff --git a/llvm/include/llvm/CodeGen/SelectionDAGNodes.h b/llvm/include/llvm/CodeGen/SelectionDAGNodes.h
index 639e9311977502..bad19173683101 100644
--- a/llvm/include/llvm/CodeGen/SelectionDAGNodes.h
+++ b/llvm/include/llvm/CodeGen/SelectionDAGNodes.h
@@ -382,6 +382,7 @@ struct SDNodeFlags {
   bool NoSignedWrap : 1;
   bool Exact : 1;
   bool Disjoint : 1;
+  bool SameSign : 1;
   bool NonNeg : 1;
   bool NoNaNs : 1;
   bool NoInfs : 1;
@@ -404,10 +405,10 @@ struct SDNodeFlags {
   /// Default constructor turns off all optimization flags.
   SDNodeFlags()
       : NoUnsignedWrap(false), NoSignedWrap(false), Exact(false),
-        Disjoint(false), NonNeg(false), NoNaNs(false), NoInfs(false),
-        NoSignedZeros(false), AllowReciprocal(false), AllowContract(false),
-        ApproximateFuncs(false), AllowReassociation(false), NoFPExcept(false),
-        Unpredictable(false) {}
+        Disjoint(false), SameSign(false), NonNeg(false), NoNaNs(false),
+        NoInfs(false), NoSignedZeros(false), AllowReciprocal(false),
+        AllowContract(false), ApproximateFuncs(false),
+        AllowReassociation(false), NoFPExcept(false), Unpredictable(false) {}
 
   /// Propagate the fast-math-flags from an IR FPMathOperator.
   void copyFMF(const FPMathOperator &FPMO) {
@@ -425,6 +426,7 @@ struct SDNodeFlags {
   void setNoSignedWrap(bool b) { NoSignedWrap = b; }
   void setExact(bool b) { Exact = b; }
   void setDisjoint(bool b) { Disjoint = b; }
+  void setSameSign(bool b) { SameSign = b; }
   void setNonNeg(bool b) { NonNeg = b; }
   void setNoNaNs(bool b) { NoNaNs = b; }
   void setNoInfs(bool b) { NoInfs = b; }
@@ -441,6 +443,7 @@ struct SDNodeFlags {
   bool hasNoSignedWrap() const { return NoSignedWrap; }
   bool hasExact() const { return Exact; }
   bool hasDisjoint() const { return Disjoint; }
+  bool hasSameSign() const { return SameSign; }
   bool hasNonNeg() const { return NonNeg; }
   bool hasNoNaNs() const { return NoNaNs; }
   bool hasNoInfs() const { return NoInfs; }
@@ -473,6 +476,7 @@ struct SDNodeFlags {
     NoSignedWrap &= Flags.NoSignedWrap;
     Exact &= Flags.Exact;
     Disjoint &= Flags.Disjoint;
+    SameSign &= Flags.SameSign;
     NonNeg &= Flags.NonNeg;
     NoNaNs &= Flags.NoNaNs;
     NoInfs &= Flags.NoInfs;
@@ -1032,7 +1036,7 @@ END_TWO_BYTE_PACK()
     SDNodeFlags Flags = getFlags();
     return Flags.hasNoUnsignedWrap() || Flags.hasNoSignedWrap() ||
            Flags.hasExact() || Flags.hasDisjoint() || Flags.hasNonNeg() ||
-           Flags.hasNoNaNs() || Flags.hasNoInfs();
+           Flags.hasNoNaNs() || Flags.hasNoInfs() || Flags.hasSameSign();
   }
 
   void setCFIType(uint32_t Type) { CFIType = Type; }
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 805b8ecf009598..35ea9419f2dd1a 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -3640,6 +3640,10 @@ void SelectionDAGBuilder::visitICmp(const ICmpInst &I) {
   SDValue Op2 = getValue(I.getOperand(1));
   ISD::CondCode Opcode = getICmpCondCode(predicate);
 
+  SDNodeFlags Flags;
+  Flags.setSameSign(I.hasSameSign());
+  SelectionDAG::FlagInserter FlagsInserter(DAG, Flags);
+
   auto &TLI = DAG.getTargetLoweringInfo();
   EVT MemVT =
       TLI.getMemValueType(DAG.getDataLayout(), I.getOperand(0)->getType());
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
index 56fc538172f9fc..24fc83b422147f 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
@@ -651,6 +651,9 @@ void SDNode::print_details(raw_ostream &OS, const SelectionDAG *G) const {
   if (getFlags().hasDisjoint())
     OS << " disjoint";
 
+  if (getFlags().hasSameSign())
+    OS << " samesign";
+
   if (getFlags().hasNonNeg())
     OS << " nneg";
 
diff --git a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
index 40f030d7b936f7..43e6a43e820b5a 100644
--- a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -1703,6 +1703,7 @@ bool TargetLowering::SimplifyDemandedBits(
   case ISD::SETCC: {
     SDValue Op0 = Op.getOperand(0);
     SDValue Op1 = Op.getOperand(1);
+    SDNodeFlags Flags = Op.getNode()->getFlags();
     ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(2))->get();
     // If (1) we only need the sign-bit, (2) the setcc operands are the same
     // width as the setcc result, and (3) the result of a setcc conforms to 0 or
@@ -1716,8 +1717,13 @@ bool TargetLowering::SimplifyDemandedBits(
       // if we don't care about FP signed-zero. The use of SETLT with FP means
       // that we don't care about NaNs.
       if (CC == ISD::SETLT && Op1.getValueType().isInteger() &&
-          (isNullConstant(Op1) || ISD::isBuildVectorAllZeros(Op1.getNode())))
+          (isNullConstant(Op1) || ISD::isBuildVectorAllZeros(Op1.getNode()))) {
+        if (Flags.hasSameSign()) {
+          Flags.setSameSign(false);
+          Op->setFlags(Flags);
+        }
         return TLO.CombineTo(Op, Op0);
+      }
 
       // TODO: Should we check for other forms of sign-bit comparisons?
       // Examples: X <= -1, X >= 0

arsenm

Missed operator==. Should InstrEmitter propagate it?

antoniofrighetto · 2024-10-16T10:23:49Z

Missed operator==. Should InstrEmitter propagate it?

Added, thanks! Extended it to MIRParser as well.

goldsteinn · 2024-10-18T17:45:37Z

llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

@@ -3640,6 +3640,10 @@ void SelectionDAGBuilder::visitICmp(const ICmpInst &I) {
  SDValue Op2 = getValue(I.getOperand(1));
  ISD::CondCode Opcode = getICmpCondCode(predicate);

+  SDNodeFlags Flags;
+  Flags.setSameSign(I.hasSameSign());
+  SelectionDAG::FlagInserter FlagsInserter(DAG, Flags);


I think this needs to be below the possible getPtrExtOrTrunc below.

goldsteinn · 2024-10-18T17:49:42Z

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

+          (isNullConstant(Op1) || ISD::isBuildVectorAllZeros(Op1.getNode()))) {
+        if (Flags.hasSameSign()) {
+          Flags.setSameSign(false);
+          Op->setFlags(Flags);


This doesn't seem necessary for the plumbing and its not clear its correct to propagate the rest of the flags.

Don't we want to stop propagating the flag in SimplifyDemandedBits?

Ahh, I misunderstood earlier.

I don't think we need to drop Op flags here. We aren't simplifying Op0 or Op1 here, just replacing Op with Op0.

That makes sense, dropped it.

arsenm · 2024-10-19T03:09:31Z

llvm/lib/CodeGen/MIRPrinter.cpp

@@ -837,6 +837,8 @@ void MIPrinter::print(const MachineInstr &MI) {
    OS << "disjoint ";
  if (MI.getFlag(MachineInstr::NoUSWrap))
    OS << "nusw ";
+  if (MI.getFlag(MachineInstr::SameSign))


Should get mir print / parse test

Testing this via GISel.

This test doesn't cover the parsing, see test/CodeGen/MIR/X86/fastmath.mir as an example

Added, thanks, think it should be on track now.

arsenm · 2024-10-19T03:09:47Z

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

+          (isNullConstant(Op1) || ISD::isBuildVectorAllZeros(Op1.getNode()))) {
+        if (Flags.hasSameSign()) {
+          Flags.setSameSign(false);
+          Op->setFlags(Flags);


Needs test and is beyond infrastructure work

Dropped it.

arsenm · 2024-10-29T21:36:43Z

llvm/test/CodeGen/MIR/X86/icmp-samesign.mir

+    samesign CMP32rr killed %0, killed %1, implicit-def $eflags
+    $al = SETCCr 2, implicit killed $eflags


Would be more sensible to have this on a G_MIR instruction as a sample

Changed the test to use generic MIR. The gMIR comes from GISel, stopping before legalization. Also rebased to main for the recent enum change.

arsenm

I feel like I just reviewed the same thing in #113090

arsenm · 2024-10-30T15:28:29Z

llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

+  SDNodeFlags Flags;
+  Flags.setSameSign(I.hasSameSign());
+  SelectionDAG::FlagInserter FlagsInserter(DAG, Flags);


Will need update after #114061

This was committed so can do this

We are still free to use FlagInserter, independently of the changes in #114061, this should be fine.

tschuett · 2024-10-30T19:00:38Z

llvm/test/CodeGen/AArch64/GlobalISel/irtranslator-icmp-samesign.ll

+  ; CHECK-NEXT:   [[ANYEXT:%[0-9]+]]:_(s32) = G_ANYEXT [[ZEXT]](s8)
+  ; CHECK-NEXT:   $w0 = COPY [[ANYEXT]](s32)
+  ; CHECK-NEXT:   RET_ReallyLR implicit $w0
+    %res = icmp samesign ult i32 %a, %b


There is no test without samesign.

tschuett · 2024-10-30T19:01:26Z

llvm/test/CodeGen/MIR/X86/icmp-samesign.mir

+    ; CHECK-NEXT: RET 0, implicit $al
+    %tmp0:_(s32) = COPY $edi
+    %tmp1:_(s32) = COPY $esi
+    %tmp4:_(s8) = samesign G_ICMP intpred(ult), %tmp0(s32), %tmp1


Again no test without samesign .

tschuett · 2024-10-30T19:02:32Z

If everything works well this time, you can rebase and limit the changes to SDAG.

tschuett · 2024-10-30T19:28:21Z

llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp

@@ -340,18 +340,18 @@ bool IRTranslator::translateCompare(const User &U,
  Register Op1 = getOrCreateVReg(*U.getOperand(1));
  Register Res = getOrCreateVReg(U);
  CmpInst::Predicate Pred = CI->getPredicate();
+  uint32_t Flags = 0;
+  if (CI)


CI is never nullptr, but it will disappear during rebase anyway.

antoniofrighetto · 2024-10-31T18:14:52Z

llvm/test/CodeGen/AArch64/dag-preserve-icmp-samesign.ll

+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT:   [[COPY:%[0-9]+]]:gpr32 = COPY $w1
+  ; CHECK-NEXT:   [[COPY1:%[0-9]+]]:gpr32 = COPY $w0
+  ; CHECK-NEXT:   [[SUBSWrr:%[0-9]+]]:gpr32 = SUBSWrr [[COPY1]], [[COPY]], implicit-def $nzcv


@arsenm Was trying to test DAG preserving of the flag (to test InstrEmitter), but it seems like the flag gets lost during legalization of the DAG (which boils down to a custom LowerSETCC for AArch64/X86). Shouldn't we want to preserve the flag there as well, or is it beyond patch scope?

The value of preserving the flag is diminishing the further back you go. I doubt anything after selection will have any use of this

Shouldn't we still preserve the flag immediately before doing instruction selection (before the very last iteration of DAG combining)?

Don't really care, it's easy enough to handle. I would agree preserving the flag in other contexts is beyond the scope of this patch

Okay, I'm dropping the test then, and merging this, if you are still fine with everything else.

arsenm · 2024-10-31T18:22:41Z

llvm/include/llvm/CodeGen/GlobalISel/MachineIRBuilder.h

@@ -1267,7 +1267,7 @@ class MachineIRBuilder {
  /// \return a MachineInstrBuilder for the newly created instruction.
  MachineInstrBuilder buildICmp(CmpInst::Predicate Pred, const DstOp &Res,
                                const SrcOp &Op0, const SrcOp &Op1,
-                                std::optional<unsigned> Flgs = std::nullopt);


Unrelated typo fix

I took the minor opportunity to fix the typo within this patch, will undo if you have a strong concern on this.

That was probably me. I vote for fix.

arsenm · 2024-10-31T18:23:11Z

llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

+  SDNodeFlags Flags;
+  Flags.setSameSign(I.hasSameSign());
+  SelectionDAG::FlagInserter FlagsInserter(DAG, Flags);


This was committed so can do this

tschuett · 2024-10-31T18:25:07Z

llvm/test/CodeGen/AArch64/dag-preserve-icmp-samesign.ll

+  ; CHECK-NEXT:   [[CMHIv2i32_:%[0-9]+]]:fpr64 = CMHIv2i32 [[COPY]], [[COPY1]]
+  ; CHECK-NEXT:   $d0 = COPY [[CMHIv2i32_]]
+  ; CHECK-NEXT:   RET_ReallyLR implicit $d0
+  %res = icmp samesign ult <2 x i32> %a, %b


Could you please add a test without samesign?

Extend recently-added poison-generating IR flag to codegen as well.

gulfemsavrun · 2024-11-01T18:24:53Z

This PR caused an assertion error:

[1321/5119](49) Building CXX object lib/Analysis/CMakeFiles/LLVMAnalysis.dir/BranchProbabilityInfo.cpp.o
FAILED: lib/Analysis/CMakeFiles/LLVMAnalysis.dir/BranchProbabilityInfo.cpp.o 
/b/s/w/ir/x/w/llvm_build/./bin/clang++ --sysroot=/b/s/w/ir/x/w/cipd/linux -DGTEST_HAS_RTTI=0 -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/b/s/w/ir/x/w/llvm_build/tools/clang/stage2-bins/lib/Analysis -I/b/s/w/ir/x/w/llvm-llvm-project/llvm/lib/Analysis -I/b/s/w/ir/x/w/llvm_build/tools/clang/stage2-bins/include -I/b/s/w/ir/x/w/llvm-llvm-project/llvm/include -isystem /b/s/w/ir/x/w/zlib_install_target/include -isystem /b/s/w/ir/x/w/zstd_install/include -stdlib=libc++ -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -flto=full -ffat-lto-objects -ffile-prefix-map=/b/s/w/ir/x/w/llvm_build/tools/clang/stage2-bins=../../../../llvm-llvm-project -ffile-prefix-map=/b/s/w/ir/x/w/llvm-llvm-project/= -no-canonical-prefixes -O3 -DNDEBUG -std=c++17 -fvisibility=default  -fno-exceptions -fno-unwind-tables -fno-asynchronous-unwind-tables -fno-rtti -MD -MT lib/Analysis/CMakeFiles/LLVMAnalysis.dir/BranchProbabilityInfo.cpp.o -MF lib/Analysis/CMakeFiles/LLVMAnalysis.dir/BranchProbabilityInfo.cpp.o.d -o lib/Analysis/CMakeFiles/LLVMAnalysis.dir/BranchProbabilityInfo.cpp.o -c /b/s/w/ir/x/w/llvm-llvm-project/llvm/lib/Analysis/BranchProbabilityInfo.cpp
clang++: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:16157: SDValue (anonymous namespace)::DAGCombiner::visitFREEZE(SDNode *): Assertion `DAG.isGuaranteedNotToBeUndefOrPoison(R, false) && "Can't create node that may be undef/poison!"' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.	Program arguments: /b/s/w/ir/x/w/llvm_build/./bin/clang++ --sysroot=/b/s/w/ir/x/w/cipd/linux -DGTEST_HAS_RTTI=0 -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/b/s/w/ir/x/w/llvm_build/tools/clang/stage2-bins/lib/Analysis -I/b/s/w/ir/x/w/llvm-llvm-project/llvm/lib/Analysis -I/b/s/w/ir/x/w/llvm_build/tools/clang/stage2-bins/include -I/b/s/w/ir/x/w/llvm-llvm-project/llvm/include -isystem /b/s/w/ir/x/w/zlib_install_target/include -isystem /b/s/w/ir/x/w/zstd_install/include -stdlib=libc++ -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -flto=full -ffat-lto-objects -ffile-prefix-map=/b/s/w/ir/x/w/llvm_build/tools/clang/stage2-bins=../../../../llvm-llvm-project -ffile-prefix-map=/b/s/w/ir/x/w/llvm-llvm-project/= -no-canonical-prefixes -O3 -DNDEBUG -std=c++17 -fvisibility=default -fno-exceptions -fno-unwind-tables -fno-asynchronous-unwind-tables -fno-rtti -MD -MT lib/Analysis/CMakeFiles/LLVMAnalysis.dir/BranchProbabilityInfo.cpp.o -MF lib/Analysis/CMakeFiles/LLVMAnalysis.dir/BranchProbabilityInfo.cpp.o.d -o lib/Analysis/CMakeFiles/LLVMAnalysis.dir/BranchProbabilityInfo.cpp.o -c /b/s/w/ir/x/w/llvm-llvm-project/llvm/lib/Analysis/BranchProbabilityInfo.cpp
1.	<eof> parser at end of file
2.	Code generation
3.	Running pass 'Function Pass Manager' on module '/b/s/w/ir/x/w/llvm-llvm-project/llvm/lib/Analysis/BranchProbabilityInfo.cpp'.
4.	Running pass 'AArch64 Instruction Selection' on function '@_ZN4llvm21BranchProbabilityInfo19calcMetadataWeightsEPKNS_10BasicBlockE'
#0 0x0000aaaacdc240c0 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/b/s/w/ir/x/w/llvm_build/./bin/clang+++0x42040c0)
clang++: error: clang frontend command failed with exit code 134 (use -v to see invocation)

https://logs.chromium.org/logs/fuchsia/buildbucket/cr-buildbucket/8732522040154573889/+/u/clang/build/stdout

antoniofrighetto · 2024-11-01T18:33:34Z

This PR caused an assertion error:

[1321/5119](49) Building CXX object lib/Analysis/CMakeFiles/LLVMAnalysis.dir/BranchProbabilityInfo.cpp.o
FAILED: lib/Analysis/CMakeFiles/LLVMAnalysis.dir/BranchProbabilityInfo.cpp.o 
/b/s/w/ir/x/w/llvm_build/./bin/clang++ --sysroot=/b/s/w/ir/x/w/cipd/linux -DGTEST_HAS_RTTI=0 -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/b/s/w/ir/x/w/llvm_build/tools/clang/stage2-bins/lib/Analysis -I/b/s/w/ir/x/w/llvm-llvm-project/llvm/lib/Analysis -I/b/s/w/ir/x/w/llvm_build/tools/clang/stage2-bins/include -I/b/s/w/ir/x/w/llvm-llvm-project/llvm/include -isystem /b/s/w/ir/x/w/zlib_install_target/include -isystem /b/s/w/ir/x/w/zstd_install/include -stdlib=libc++ -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -flto=full -ffat-lto-objects -ffile-prefix-map=/b/s/w/ir/x/w/llvm_build/tools/clang/stage2-bins=../../../../llvm-llvm-project -ffile-prefix-map=/b/s/w/ir/x/w/llvm-llvm-project/= -no-canonical-prefixes -O3 -DNDEBUG -std=c++17 -fvisibility=default  -fno-exceptions -fno-unwind-tables -fno-asynchronous-unwind-tables -fno-rtti -MD -MT lib/Analysis/CMakeFiles/LLVMAnalysis.dir/BranchProbabilityInfo.cpp.o -MF lib/Analysis/CMakeFiles/LLVMAnalysis.dir/BranchProbabilityInfo.cpp.o.d -o lib/Analysis/CMakeFiles/LLVMAnalysis.dir/BranchProbabilityInfo.cpp.o -c /b/s/w/ir/x/w/llvm-llvm-project/llvm/lib/Analysis/BranchProbabilityInfo.cpp
clang++: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:16157: SDValue (anonymous namespace)::DAGCombiner::visitFREEZE(SDNode *): Assertion `DAG.isGuaranteedNotToBeUndefOrPoison(R, false) && "Can't create node that may be undef/poison!"' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.	Program arguments: /b/s/w/ir/x/w/llvm_build/./bin/clang++ --sysroot=/b/s/w/ir/x/w/cipd/linux -DGTEST_HAS_RTTI=0 -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/b/s/w/ir/x/w/llvm_build/tools/clang/stage2-bins/lib/Analysis -I/b/s/w/ir/x/w/llvm-llvm-project/llvm/lib/Analysis -I/b/s/w/ir/x/w/llvm_build/tools/clang/stage2-bins/include -I/b/s/w/ir/x/w/llvm-llvm-project/llvm/include -isystem /b/s/w/ir/x/w/zlib_install_target/include -isystem /b/s/w/ir/x/w/zstd_install/include -stdlib=libc++ -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -flto=full -ffat-lto-objects -ffile-prefix-map=/b/s/w/ir/x/w/llvm_build/tools/clang/stage2-bins=../../../../llvm-llvm-project -ffile-prefix-map=/b/s/w/ir/x/w/llvm-llvm-project/= -no-canonical-prefixes -O3 -DNDEBUG -std=c++17 -fvisibility=default -fno-exceptions -fno-unwind-tables -fno-asynchronous-unwind-tables -fno-rtti -MD -MT lib/Analysis/CMakeFiles/LLVMAnalysis.dir/BranchProbabilityInfo.cpp.o -MF lib/Analysis/CMakeFiles/LLVMAnalysis.dir/BranchProbabilityInfo.cpp.o.d -o lib/Analysis/CMakeFiles/LLVMAnalysis.dir/BranchProbabilityInfo.cpp.o -c /b/s/w/ir/x/w/llvm-llvm-project/llvm/lib/Analysis/BranchProbabilityInfo.cpp
1.	<eof> parser at end of file
2.	Code generation
3.	Running pass 'Function Pass Manager' on module '/b/s/w/ir/x/w/llvm-llvm-project/llvm/lib/Analysis/BranchProbabilityInfo.cpp'.
4.	Running pass 'AArch64 Instruction Selection' on function '@_ZN4llvm21BranchProbabilityInfo19calcMetadataWeightsEPKNS_10BasicBlockE'
#0 0x0000aaaacdc240c0 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/b/s/w/ir/x/w/llvm_build/./bin/clang+++0x42040c0)
clang++: error: clang frontend command failed with exit code 134 (use -v to see invocation)

https://logs.chromium.org/logs/fuchsia/buildbucket/cr-buildbucket/8732522040154573889/+/u/clang/build/stdout

Patch attempting to fix the issue: #114582.

This patch intersects poison-generating flags after CSE to fix assertion failure reported in #112354 (comment). Co-authored-by: Antonio Frighetto <[email protected]>

This patch intersects poison-generating flags after CSE to fix assertion failure reported in llvm#112354 (comment). Co-authored-by: Antonio Frighetto <[email protected]>

antoniofrighetto requested review from arsenm, nikic, dtcxzyw and topperc October 15, 2024 13:15

llvmbot added the llvm:SelectionDAG SelectionDAGISel as well label Oct 15, 2024

arsenm reviewed Oct 15, 2024

View reviewed changes

antoniofrighetto changed the title ~~[SelectionDAG] Add preliminary plumbing for samesign flag~~ [CodeGen] Add preliminary plumbing for samesign flag Oct 16, 2024

dtcxzyw mentioned this pull request Oct 17, 2024

[IR] Add samesign flag to icmp instruction #111421

Closed

5 tasks

dtcxzyw requested review from RKSimon and goldsteinn October 18, 2024 13:22

goldsteinn reviewed Oct 18, 2024

View reviewed changes

arsenm reviewed Oct 19, 2024

View reviewed changes

llvmbot added backend:AArch64 llvm:globalisel labels Oct 23, 2024

arsenm reviewed Oct 29, 2024

View reviewed changes

antoniofrighetto force-pushed the feature/sdag-samesign branch from 8bcf219 to 7c49142 Compare October 30, 2024 14:03

arsenm approved these changes Oct 30, 2024

View reviewed changes

arsenm reviewed Oct 30, 2024

View reviewed changes

tschuett reviewed Oct 30, 2024

View reviewed changes

antoniofrighetto force-pushed the feature/sdag-samesign branch from 7c49142 to 4f95fbd Compare October 31, 2024 18:10

antoniofrighetto changed the title ~~[CodeGen] Add preliminary plumbing for samesign flag~~ [SelectionDAG] Add preliminary plumbing for samesign flag Oct 31, 2024

antoniofrighetto commented Oct 31, 2024

View reviewed changes

arsenm reviewed Oct 31, 2024

View reviewed changes

tschuett reviewed Oct 31, 2024

View reviewed changes

antoniofrighetto force-pushed the feature/sdag-samesign branch from 4f95fbd to 54a58b1 Compare October 31, 2024 18:46

[SelectionDAG] Add preliminary plumbing for samesign flag

19c8475

Extend recently-added poison-generating IR flag to codegen as well.

antoniofrighetto force-pushed the feature/sdag-samesign branch from 54a58b1 to 19c8475 Compare October 31, 2024 18:48

antoniofrighetto merged commit 19c8475 into llvm:main Oct 31, 2024
3 of 5 checks passed

dtcxzyw mentioned this pull request Nov 2, 2024

[SDAG] Intersect poison-generating flags after CSE #114650

Merged

		samesign CMP32rr killed %0, killed %1, implicit-def $eflags
		$al = SETCCr 2, implicit killed $eflags

[SelectionDAG] Add preliminary plumbing for samesign flag #112354

[SelectionDAG] Add preliminary plumbing for samesign flag #112354

Uh oh!

Conversation

antoniofrighetto commented Oct 15, 2024

Uh oh!

llvmbot commented Oct 15, 2024 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

arsenm left a comment

Choose a reason for hiding this comment

Uh oh!

antoniofrighetto commented Oct 16, 2024

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

arsenm left a comment

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

tschuett commented Oct 30, 2024

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Uh oh!

gulfemsavrun commented Nov 1, 2024

Uh oh!

[SelectionDAG] Add preliminary plumbing for `samesign` flag #112354

[SelectionDAG] Add preliminary plumbing for `samesign` flag #112354

llvmbot commented Oct 15, 2024 •

edited

Loading