[ARM][TargetLowering] Combine Level should not be a factor in shouldFoldConstantShiftPairToMask (NFC) #156949
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…oldConstantShiftPairToMask This should be based on the type and instructions, and only thumb uses combine level anyway.
llvmbot
added
backend:ARM
backend:AArch64
backend:MIPS
backend:X86
llvm:SelectionDAG
|
@llvm/pr-subscribers-backend-x86 @llvm/pr-subscribers-backend-mips Author: AZero13 (AZero13) ChangesThis should be based on the type and instructions, and only thumb uses combine level anyway. Full diff: https://github.com/llvm/llvm-project/pull/156949.diff 10 Files Affected:
diff --git a/llvm/include/llvm/CodeGen/TargetLowering.h b/llvm/include/llvm/CodeGen/TargetLowering.h
index 438b6ff55c85f..119209fd0a6fb 100644
--- a/llvm/include/llvm/CodeGen/TargetLowering.h
+++ b/llvm/include/llvm/CodeGen/TargetLowering.h
@@ -854,8 +854,7 @@ class LLVM_ABI TargetLoweringBase {
/// This is usually true on most targets. But some targets, like Thumb1,
/// have immediate shift instructions, but no immediate "and" instruction;
/// this makes the fold unprofitable.
- virtual bool shouldFoldConstantShiftPairToMask(const SDNode *N,
- CombineLevel Level) const {
+ virtual bool shouldFoldConstantShiftPairToMask(const SDNode *N) const {
return true;
}
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index bed3c42473e27..ec5ce31fc8777 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -10521,7 +10521,7 @@ SDValue DAGCombiner::visitSHL(SDNode *N) {
// folding this will increase the total number of instructions.
if (N0.getOpcode() == ISD::SRL &&
(N0.getOperand(1) == N1 || N0.hasOneUse()) &&
- TLI.shouldFoldConstantShiftPairToMask(N, Level)) {
+ TLI.shouldFoldConstantShiftPairToMask(N)) {
if (ISD::matchBinaryPredicate(N1, N0.getOperand(1), MatchShiftAmount,
/*AllowUndefs*/ false,
/*AllowTypeMismatch*/ true)) {
@@ -11100,7 +11100,7 @@ SDValue DAGCombiner::visitSRL(SDNode *N) {
// fold (srl (shl x, c1), c2) -> (and (shl x, (sub c1, c2), MASK) or
// (and (srl x, (sub c2, c1), MASK)
if ((N0.getOperand(1) == N1 || N0->hasOneUse()) &&
- TLI.shouldFoldConstantShiftPairToMask(N, Level)) {
+ TLI.shouldFoldConstantShiftPairToMask(N)) {
auto MatchShiftAmount = [OpSizeInBits](ConstantSDNode *LHS,
ConstantSDNode *RHS) {
const APInt &LHSC = LHS->getAPIntValue();
diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
index b7011e0ea1669..77bc780295a88 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -18280,7 +18280,7 @@ bool AArch64TargetLowering::isDesirableToCommuteXorWithShift(
}
bool AArch64TargetLowering::shouldFoldConstantShiftPairToMask(
- const SDNode *N, CombineLevel Level) const {
+ const SDNode *N) const {
assert(((N->getOpcode() == ISD::SHL &&
N->getOperand(0).getOpcode() == ISD::SRL) ||
(N->getOpcode() == ISD::SRL &&
diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.h b/llvm/lib/Target/AArch64/AArch64ISelLowering.h
index 46738365080f9..6ad7c6f2a5975 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.h
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.h
@@ -297,8 +297,7 @@ class AArch64TargetLowering : public TargetLowering {
bool isDesirableToCommuteXorWithShift(const SDNode *N) const override;
/// Return true if it is profitable to fold a pair of shifts into a mask.
- bool shouldFoldConstantShiftPairToMask(const SDNode *N,
- CombineLevel Level) const override;
+ bool shouldFoldConstantShiftPairToMask(const SDNode *N) const override;
bool shouldFoldSelectWithIdentityConstant(unsigned BinOpcode, EVT VT,
unsigned SelectOpcode, SDValue X,
diff --git a/llvm/lib/Target/ARM/ARMISelLowering.cpp b/llvm/lib/Target/ARM/ARMISelLowering.cpp
index b5c01eafcf108..cb39a40f88d31 100644
--- a/llvm/lib/Target/ARM/ARMISelLowering.cpp
+++ b/llvm/lib/Target/ARM/ARMISelLowering.cpp
@@ -13878,7 +13878,7 @@ bool ARMTargetLowering::isDesirableToCommuteXorWithShift(
}
bool ARMTargetLowering::shouldFoldConstantShiftPairToMask(
- const SDNode *N, CombineLevel Level) const {
+ const SDNode *N) const {
assert(((N->getOpcode() == ISD::SHL &&
N->getOperand(0).getOpcode() == ISD::SRL) ||
(N->getOpcode() == ISD::SRL &&
@@ -13888,7 +13888,8 @@ bool ARMTargetLowering::shouldFoldConstantShiftPairToMask(
if (!Subtarget->isThumb1Only())
return true;
- if (Level == BeforeLegalizeTypes)
+ EVT VT = N->getValueType(0);
+ if (VT.getScalarSizeInBits() > 32)
return true;
return false;
diff --git a/llvm/lib/Target/ARM/ARMISelLowering.h b/llvm/lib/Target/ARM/ARMISelLowering.h
index 196ecb1b9f678..fbf1d9b48bb4a 100644
--- a/llvm/lib/Target/ARM/ARMISelLowering.h
+++ b/llvm/lib/Target/ARM/ARMISelLowering.h
@@ -770,8 +770,7 @@ class VectorType;
bool isDesirableToCommuteXorWithShift(const SDNode *N) const override;
- bool shouldFoldConstantShiftPairToMask(const SDNode *N,
- CombineLevel Level) const override;
+ bool shouldFoldConstantShiftPairToMask(const SDNode *N) const override;
bool shouldFoldSelectWithIdentityConstant(unsigned BinOpcode, EVT VT,
unsigned SelectOpcode, SDValue X,
diff --git a/llvm/lib/Target/Mips/MipsISelLowering.cpp b/llvm/lib/Target/Mips/MipsISelLowering.cpp
index 1491300e37d3e..956625487be99 100644
--- a/llvm/lib/Target/Mips/MipsISelLowering.cpp
+++ b/llvm/lib/Target/Mips/MipsISelLowering.cpp
@@ -1306,7 +1306,7 @@ bool MipsTargetLowering::hasBitTest(SDValue X, SDValue Y) const {
}
bool MipsTargetLowering::shouldFoldConstantShiftPairToMask(
- const SDNode *N, CombineLevel Level) const {
+ const SDNode *N) const {
assert(((N->getOpcode() == ISD::SHL &&
N->getOperand(0).getOpcode() == ISD::SRL) ||
(N->getOpcode() == ISD::SRL &&
diff --git a/llvm/lib/Target/Mips/MipsISelLowering.h b/llvm/lib/Target/Mips/MipsISelLowering.h
index c65c76ccffc75..25a0bf9b797d5 100644
--- a/llvm/lib/Target/Mips/MipsISelLowering.h
+++ b/llvm/lib/Target/Mips/MipsISelLowering.h
@@ -290,8 +290,7 @@ class TargetRegisterClass;
bool isCheapToSpeculateCttz(Type *Ty) const override;
bool isCheapToSpeculateCtlz(Type *Ty) const override;
bool hasBitTest(SDValue X, SDValue Y) const override;
- bool shouldFoldConstantShiftPairToMask(const SDNode *N,
- CombineLevel Level) const override;
+ bool shouldFoldConstantShiftPairToMask(const SDNode *N) const override;
/// Return the register type for a given MVT, ensuring vectors are treated
/// as a series of gpr sized integers.
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 08ae0d52d795e..d69fd099df875 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -3638,7 +3638,7 @@ bool X86TargetLowering::preferScalarizeSplat(SDNode *N) const {
}
bool X86TargetLowering::shouldFoldConstantShiftPairToMask(
- const SDNode *N, CombineLevel Level) const {
+ const SDNode *N) const {
assert(((N->getOpcode() == ISD::SHL &&
N->getOperand(0).getOpcode() == ISD::SRL) ||
(N->getOpcode() == ISD::SRL &&
@@ -3653,7 +3653,7 @@ bool X86TargetLowering::shouldFoldConstantShiftPairToMask(
// the fold for non-splats yet.
return N->getOperand(1) == N->getOperand(0).getOperand(1);
}
- return TargetLoweringBase::shouldFoldConstantShiftPairToMask(N, Level);
+ return TargetLoweringBase::shouldFoldConstantShiftPairToMask(N);
}
bool X86TargetLowering::shouldFoldMaskToVariableShiftPair(SDValue Y) const {
diff --git a/llvm/lib/Target/X86/X86ISelLowering.h b/llvm/lib/Target/X86/X86ISelLowering.h
index d888f9f593ee7..2fcf33938a596 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.h
+++ b/llvm/lib/Target/X86/X86ISelLowering.h
@@ -1240,8 +1240,7 @@ namespace llvm {
getJumpConditionMergingParams(Instruction::BinaryOps Opc, const Value *Lhs,
const Value *Rhs) const override;
- bool shouldFoldConstantShiftPairToMask(const SDNode *N,
- CombineLevel Level) const override;
+ bool shouldFoldConstantShiftPairToMask(const SDNode *N) const override;
bool shouldFoldMaskToVariableShiftPair(SDValue Y) const override;
|
AZero13
changed the title
arsenm
approved these changes
Oct 11, 2025
|
LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/94/builds/11655 Here is the relevant piece of the build log for the reference |
DharuniRAcharya
pushed a commit
to DharuniRAcharya/llvm-project
that referenced
this pull request
Oct 13, 2025
…oldConstantShiftPairToMask (NFC) (llvm#156949) This should be based on the type and instructions, and only thumb uses combine level anyway.
akadutta
pushed a commit
to akadutta/llvm-project
that referenced
this pull request
Oct 14, 2025
…oldConstantShiftPairToMask (NFC) (llvm#156949) This should be based on the type and instructions, and only thumb uses combine level anyway.
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This should be based on the type and instructions, and only thumb uses combine level anyway.