Skip to content

[DirectX] Add emulation for fp16 types of llvm.is.fpclass #157505

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 2 commits into from
Sep 8, 2025
Merged

[DirectX] Add emulation for fp16 types of llvm.is.fpclass #157505

Show file tree
Hide file tree
Changes from 1 commit
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
b198a1e
[DirectX] Add emulation for fp16 types of llvm.is.fpclass
farzonl Sep 8, 2025
fa1373e
fix bad merge
farzonl Sep 8, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
112 changes: 112 additions & 0 deletions llvm/lib/Target/DirectX/DXILIntrinsicExpansion.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -86,6 +86,115 @@ static Value *expand16BitIsInf(CallInst *Orig) {
return B3;
}

static Value *expand16BitIsNaN(CallInst *Orig) {
Module *M = Orig->getModule();
if (M->getTargetTriple().getDXILVersion() >= VersionTuple(1, 9))
return nullptr;

Value *Val = Orig->getOperand(0);
Type *ValTy = Val->getType();
if (!ValTy->getScalarType()->isHalfTy())
return nullptr;

IRBuilder<> Builder(Orig);
Type *IType = Type::getInt16Ty(M->getContext());

Constant *ExpBitMask =
ValTy->isVectorTy()
? ConstantVector::getSplat(
ElementCount::getFixed(
cast<FixedVectorType>(ValTy)->getNumElements()),
ConstantInt::get(IType, 0x7c00))
: ConstantInt::get(IType, 0x7c00);
Constant *SigBitMask =
ValTy->isVectorTy()
? ConstantVector::getSplat(
ElementCount::getFixed(
cast<FixedVectorType>(ValTy)->getNumElements()),
ConstantInt::get(IType, 0x3ff))
: ConstantInt::get(IType, 0x3ff);

Constant *Zero =
ValTy->isVectorTy()
? ConstantVector::getSplat(
ElementCount::getFixed(
cast<FixedVectorType>(ValTy)->getNumElements()),
ConstantInt::get(IType, 0))
: ConstantInt::get(IType, 0);

Value *IVal = Builder.CreateBitCast(Val, ExpBitMask->getType());
Value *Exp = Builder.CreateAnd(IVal, ExpBitMask);
Value *B1 = Builder.CreateICmpEQ(Exp, ExpBitMask);

Value *Sig = Builder.CreateAnd(IVal, SigBitMask);
Value *B2 = Builder.CreateICmpNE(Sig, Zero);
Value *B3 = Builder.CreateAnd(B1, B2);
return B3;
}

static Value *expand16BitIsFinite(CallInst *Orig) {
Module *M = Orig->getModule();
if (M->getTargetTriple().getDXILVersion() >= VersionTuple(1, 9))
return nullptr;

Value *Val = Orig->getOperand(0);
Type *ValTy = Val->getType();
if (!ValTy->getScalarType()->isHalfTy())
return nullptr;

IRBuilder<> Builder(Orig);
Type *IType = Type::getInt16Ty(M->getContext());

Constant *ExpBitMask =
ValTy->isVectorTy()
? ConstantVector::getSplat(
ElementCount::getFixed(
cast<FixedVectorType>(ValTy)->getNumElements()),
ConstantInt::get(IType, 0x7c00))
: ConstantInt::get(IType, 0x7c00);

Value *IVal = Builder.CreateBitCast(Val, ExpBitMask->getType());
Value *Exp = Builder.CreateAnd(IVal, ExpBitMask);
Value *B1 = Builder.CreateICmpNE(Exp, ExpBitMask);
return B1;
}

static Value *expand16BitIsNormal(CallInst *Orig) {
Module *M = Orig->getModule();
if (M->getTargetTriple().getDXILVersion() >= VersionTuple(1, 9))
return nullptr;

Value *Val = Orig->getOperand(0);
Type *ValTy = Val->getType();
if (!ValTy->getScalarType()->isHalfTy())
return nullptr;

IRBuilder<> Builder(Orig);
Type *IType = Type::getInt16Ty(M->getContext());

Constant *ExpBitMask =
ValTy->isVectorTy()
? ConstantVector::getSplat(
ElementCount::getFixed(
cast<FixedVectorType>(ValTy)->getNumElements()),
ConstantInt::get(IType, 0x7c00))
: ConstantInt::get(IType, 0x7c00);
Constant *Zero =
ValTy->isVectorTy()
? ConstantVector::getSplat(
ElementCount::getFixed(
cast<FixedVectorType>(ValTy)->getNumElements()),
ConstantInt::get(IType, 0))
: ConstantInt::get(IType, 0);

Value *IVal = Builder.CreateBitCast(Val, ExpBitMask->getType());
Value *Exp = Builder.CreateAnd(IVal, ExpBitMask);
Value *NotAllZeroes = Builder.CreateICmpNE(Exp, Zero);
Value *NotAllOnes = Builder.CreateICmpNE(Exp, ExpBitMask);
Value *B1 = Builder.CreateAnd(NotAllZeroes, NotAllOnes);
return B1;
}

static bool isIntrinsicExpansion(Function &F) {
switch (F.getIntrinsicID()) {
case Intrinsic::abs:
Expand Down Expand Up @@ -342,8 +451,11 @@ static Value *expandIsFPClass(CallInst *Orig) {
case FPClassTest::fcInf:
return expand16BitIsInf(Orig);
case FPClassTest::fcNan:
return expand16BitIsNaN(Orig);
case FPClassTest::fcNormal:
return expand16BitIsNormal(Orig);
case FPClassTest::fcFinite:
return expand16BitIsFinite(Orig);
return nullptr;
}

Expand Down
150 changes: 149 additions & 1 deletion llvm/test/CodeGen/DirectX/is_fpclass.ll
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -46,6 +46,25 @@ entry:
ret i1 %0
}

define noundef i1 @isnanh(half noundef %a) {
; CHECK-LABEL: define noundef i1 @isnanh(
; CHECK-SAME: half noundef [[A:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*:]]
; SM69CHECK-NEXT: [[TMP0:%.*]] = call i1 @dx.op.isSpecialFloat.f16(i32 8, half [[A]]) #[[ATTR0:[0-9]+]]
; SMOLDCHECK-NEXT: [[BITCAST:%.*]] = bitcast half [[A]] to i16
; SMOLDCHECK-NEXT: [[AND:%.*]] = and i16 [[BITCAST]], 31744
; SMOLDCHECK-NEXT: [[CMPHIGH:%.*]] = icmp eq i16 [[AND]], 31744
; SMOLDCHECK-NEXT: [[ANDLOW:%.*]] = and i16 [[BITCAST]], 1023
; SMOLDCHECK-NEXT: [[CMPZERO:%.*]] = icmp ne i16 [[ANDLOW]], 0
; SMOLDCHECK-NEXT: [[ANDLOW:%.*]] = and i1 [[CMPHIGH]], [[CMPZERO]]
; SMOLDCHECK-NEXT: ret i1 [[ANDLOW]]
; SM69CHECK-NEXT: ret i1 [[TMP0]]
;
entry:
%0 = call i1 @llvm.is.fpclass.f16(half %a, i32 3)
ret i1 %0
}

define noundef <2 x i1> @isnanv2(<2 x float> noundef %a) {
; CHECK-LABEL: define noundef <2 x i1> @isnanv2(
; CHECK-SAME: <2 x float> noundef [[A:%.*]]) {
Expand All @@ -63,6 +82,40 @@ entry:
ret <2 x i1> %0
}

define noundef <2 x i1> @isnanhv2(<2 x half> noundef %a) {
; CHECK-LABEL: define noundef <2 x i1> @isnanhv2(
; CHECK-SAME: <2 x half> noundef [[A:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*:]]
; CHECK-NEXT: [[A_I0:%.*]] = extractelement <2 x half> [[A]], i64 0
; SM69CHECK-NEXT: [[DOTI02:%.*]] = call i1 @dx.op.isSpecialFloat.f16(i32 8, half [[A_I0]]) #[[ATTR0:[0-9]+]]
; SM69CHECK-NEXT: [[A_I1:%.*]] = extractelement <2 x half> [[A]], i64 1
; SM69CHECK-NEXT: [[DOTI11:%.*]] = call i1 @dx.op.isSpecialFloat.f16(i32 8, half [[A_I1]]) #[[ATTR0]]
; SM69CHECK-NEXT: [[DOTUPTO0:%.*]] = insertelement <2 x i1> poison, i1 [[DOTI02]], i64 0
; SM69CHECK-NEXT: [[TMP0:%.*]] = insertelement <2 x i1> [[DOTUPTO0]], i1 [[DOTI11]], i64 1
; SM69CHECK-NEXT: ret <2 x i1> [[TMP0]]
;
; SMOLDCHECK-NEXT: [[DOTI0:%.*]] = bitcast half [[A_I0]] to i16
; SMOLDCHECK-NEXT: [[A_I1:%.*]] = extractelement <2 x half> [[A]], i64 1
; SMOLDCHECK-NEXT: [[DOTI1:%.*]] = bitcast half [[A_I1]] to i16
; SMOLDCHECK-NEXT: [[DOTI01:%.*]] = and i16 [[DOTI0]], 31744
; SMOLDCHECK-NEXT: [[DOTI12:%.*]] = and i16 [[DOTI1]], 31744
; SMOLDCHECK-NEXT: [[DOTI03:%.*]] = icmp eq i16 [[DOTI01]], 31744
; SMOLDCHECK-NEXT: [[DOTI14:%.*]] = icmp eq i16 [[DOTI12]], 31744
; SMOLDCHECK-NEXT: [[DOTI05:%.*]] = and i16 [[DOTI0]], 1023
; SMOLDCHECK-NEXT: [[DOTI16:%.*]] = and i16 [[DOTI1]], 1023
; SMOLDCHECK-NEXT: [[DOTI07:%.*]] = icmp ne i16 [[DOTI05]], 0
; SMOLDCHECK-NEXT: [[DOTI18:%.*]] = icmp ne i16 [[DOTI16]], 0
; SMOLDCHECK-NEXT: [[DOTI09:%.*]] = and i1 [[DOTI03]], [[DOTI07]]
; SMOLDCHECK-NEXT: [[DOTI110:%.*]] = and i1 [[DOTI14]], [[DOTI18]]
; SMOLDCHECK-NEXT: [[DOTUPTO015:%.*]] = insertelement <2 x i1> poison, i1 [[DOTI09]], i64 0
; SMOLDCHECK-NEXT: [[TMP0:%.*]] = insertelement <2 x i1> [[DOTUPTO015]], i1 [[DOTI110]], i64 1
; SMOLDCHECK-NEXT: ret <2 x i1> [[TMP0]]
;
entry:
%0 = call <2 x i1> @llvm.is.fpclass.v2f16(<2 x half> %a, i32 3)
ret <2 x i1> %0
}

define noundef i1 @isinf(float noundef %a) {
; CHECK-LABEL: define noundef i1 @isinf(
; CHECK-SAME: float noundef [[A:%.*]]) {
Expand All @@ -80,7 +133,7 @@ define noundef i1 @isinfh(half noundef %a) {
; CHECK-SAME: half noundef [[A:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*:]]
; SM69CHECK-NEXT: [[ISINF:%.*]] = call i1 @dx.op.isSpecialFloat.f16(i32 9, half [[A]]) #[[ATTR0]]
; SMOLDCHECK-NEXT: [[BITCAST:%.*]] = bitcast half %a to i16
; SMOLDCHECK-NEXT: [[BITCAST:%.*]] = bitcast half [[A]] to i16
; SMOLDCHECK-NEXT: [[CMPHIGH:%.*]] = icmp eq i16 [[BITCAST]], 31744
; SMOLDCHECK-NEXT: [[CMPLOW:%.*]] = icmp eq i16 [[BITCAST]], -1024
; SMOLDCHECK-NEXT: [[OR:%.*]] = or i1 [[CMPHIGH]], [[CMPLOW]]
Expand Down Expand Up @@ -121,6 +174,22 @@ entry:
ret i1 %0
}

define noundef i1 @isfiniteh(half noundef %a) {
; CHECK-LABEL: define noundef i1 @isfiniteh(
; CHECK-SAME: half noundef [[A:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*:]]
; SM69CHECK-NEXT: [[TMP0:%.*]] = call i1 @dx.op.isSpecialFloat.f16(i32 10, half [[A]]) #[[ATTR0]]
; SMOLDCHECK-NEXT: [[BITCAST:%.*]] = bitcast half [[A]] to i16
; SMOLDCHECK-NEXT: [[AND:%.*]] = and i16 [[BITCAST]], 31744
; SMOLDCHECK-NEXT: [[CMPHIGH:%.*]] = icmp ne i16 [[AND]], 31744
; SMOLDCHECK-NEXT: ret i1 [[CMPHIGH]]
; SM69CHECK-NEXT: ret i1 [[TMP0]]
;
entry:
%0 = call i1 @llvm.is.fpclass.f16(half %a, i32 504)
ret i1 %0
}

define noundef <2 x i1> @isfinitev2(<2 x float> noundef %a) {
; CHECK-LABEL: define noundef <2 x i1> @isfinitev2(
; CHECK-SAME: <2 x float> noundef [[A:%.*]]) {
Expand All @@ -138,6 +207,35 @@ entry:
ret <2 x i1> %0
}

define noundef <2 x i1> @isfinitehv2(<2 x half> noundef %a) {
; CHECK-LABEL: define noundef <2 x i1> @isfinitehv2(
; CHECK-SAME: <2 x half> noundef [[A:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*:]]
; SM69CHECK-NEXT: [[A_I0:%.*]] = extractelement <2 x half> [[A]], i64 0
; SM69CHECK-NEXT: [[DOTI02:%.*]] = call i1 @dx.op.isSpecialFloat.f16(i32 10, half [[A_I0]]) #[[ATTR0:[0-9]+]]
; SM69CHECK-NEXT: [[A_I1:%.*]] = extractelement <2 x half> [[A]], i64 1
; SM69CHECK-NEXT: [[DOTI11:%.*]] = call i1 @dx.op.isSpecialFloat.f16(i32 10, half [[A_I1]]) #[[ATTR0]]
; SM69CHECK-NEXT: [[DOTUPTO0:%.*]] = insertelement <2 x i1> poison, i1 [[DOTI02]], i64 0
; SM69CHECK-NEXT: [[TMP0:%.*]] = insertelement <2 x i1> [[DOTUPTO0]], i1 [[DOTI11]], i64 1
; SM69CHECK-NEXT: ret <2 x i1> [[TMP0]]
;
; SMOLDCHECK-NEXT: [[A_I0:%.*]] = extractelement <2 x half> [[A]], i64 0
; SMOLDCHECK-NEXT: [[DOTI0:%.*]] = bitcast half [[A_I0]] to i16
; SMOLDCHECK-NEXT: [[A_I1:%.*]] = extractelement <2 x half> [[A]], i64 1
; SMOLDCHECK-NEXT: [[DOTI1:%.*]] = bitcast half [[A_I1]] to i16
; SMOLDCHECK-NEXT: [[DOTI01:%.*]] = and i16 [[DOTI0]], 31744
; SMOLDCHECK-NEXT: [[DOTI12:%.*]] = and i16 [[DOTI1]], 31744
; SMOLDCHECK-NEXT: [[DOTI03:%.*]] = icmp ne i16 [[DOTI01]], 31744
; SMOLDCHECK-NEXT: [[DOTI14:%.*]] = icmp ne i16 [[DOTI12]], 31744
; SMOLDCHECK-NEXT: [[DOTUPTO06:%.*]] = insertelement <2 x i1> poison, i1 [[DOTI03]], i64 0
; SMOLDCHECK-NEXT: [[TMP0:%.*]] = insertelement <2 x i1> [[DOTUPTO06]], i1 [[DOTI14]], i64 1
; SMOLDCHECK-NEXT: ret <2 x i1> [[TMP0]]
;
entry:
%0 = call <2 x i1> @llvm.is.fpclass.v2f16(<2 x half> %a, i32 504)
ret <2 x i1> %0
}

define noundef i1 @isnormal(float noundef %a) {
; CHECK-LABEL: define noundef i1 @isnormal(
; CHECK-SAME: float noundef [[A:%.*]]) {
Expand All @@ -150,6 +248,24 @@ entry:
ret i1 %0
}

define noundef i1 @isnormalh(half noundef %a) {
; CHECK-LABEL: define noundef i1 @isnormalh(
; CHECK-SAME: half noundef [[A:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*:]]
; SM69CHECK-NEXT: [[TMP0:%.*]] = call i1 @dx.op.isSpecialFloat.f16(i32 11, half [[A]]) #[[ATTR0]]
; SMOLDCHECK-NEXT: [[BITCAST:%.*]] = bitcast half [[A]] to i16
; SMOLDCHECK-NEXT: [[AND:%.*]] = and i16 [[BITCAST]], 31744
; SMOLDCHECK-NEXT: [[CMPZERO:%.*]] = icmp ne i16 [[AND]], 0
; SMOLDCHECK-NEXT: [[CMPHIGH:%.*]] = icmp ne i16 [[AND]], 31744
; SMOLDCHECK-NEXT: [[ANDCMP:%.*]] = and i1 [[CMPZERO]], [[CMPHIGH]]
; SMOLDCHECK-NEXT: ret i1 [[ANDCMP]]
; SM69CHECK-NEXT: ret i1 [[TMP0]]
;
entry:
%0 = call i1 @llvm.is.fpclass.f16(half %a, i32 264)
ret i1 %0
}

define noundef <2 x i1> @isnormalv2(<2 x float> noundef %a) {
; CHECK-LABEL: define noundef <2 x i1> @isnormalv2(
; CHECK-SAME: <2 x float> noundef [[A:%.*]]) {
Expand All @@ -167,5 +283,37 @@ entry:
ret <2 x i1> %0
}

define noundef <2 x i1> @isnormalhv2(<2 x half> noundef %a) {
; CHECK-LABEL: define noundef <2 x i1> @isnormalhv2(
; CHECK-SAME: <2 x half> noundef [[A:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*:]]
; CHECK-NEXT: [[A_I0:%.*]] = extractelement <2 x half> [[A]], i64 0
; SM69CHECK-NEXT: [[DOTI02:%.*]] = call i1 @dx.op.isSpecialFloat.f16(i32 11, half [[A_I0]]) #[[ATTR0:[0-9]+]]
; SM69CHECK-NEXT: [[A_I1:%.*]] = extractelement <2 x half> [[A]], i64 1
; SM69CHECK-NEXT: [[DOTI11:%.*]] = call i1 @dx.op.isSpecialFloat.f16(i32 11, half [[A_I1]]) #[[ATTR0]]
; SM69CHECK-NEXT: [[DOTUPTO0:%.*]] = insertelement <2 x i1> poison, i1 [[DOTI02]], i64 0
; SM69CHECK-NEXT: [[TMP0:%.*]] = insertelement <2 x i1> [[DOTUPTO0]], i1 [[DOTI11]], i64 1
; SM69CHECK-NEXT: ret <2 x i1> [[TMP0]]
;
; SMOLDCHECK-NEXT: [[DOTI0:%.*]] = bitcast half [[A_I0]] to i16
; SMOLDCHECK-NEXT: [[A_I1:%.*]] = extractelement <2 x half> [[A]], i64 1
; SMOLDCHECK-NEXT: [[DOTI1:%.*]] = bitcast half [[A_I1]] to i16
; SMOLDCHECK-NEXT: [[DOTI01:%.*]] = and i16 [[DOTI0]], 31744
; SMOLDCHECK-NEXT: [[DOTI12:%.*]] = and i16 [[DOTI1]], 31744
; SMOLDCHECK-NEXT: [[DOTI03:%.*]] = icmp ne i16 [[DOTI01]], 0
; SMOLDCHECK-NEXT: [[DOTI14:%.*]] = icmp ne i16 [[DOTI12]], 0
; SMOLDCHECK-NEXT: [[DOTI05:%.*]] = icmp ne i16 [[DOTI01]], 31744
; SMOLDCHECK-NEXT: [[DOTI16:%.*]] = icmp ne i16 [[DOTI12]], 31744
; SMOLDCHECK-NEXT: [[DOTI07:%.*]] = and i1 [[DOTI03]], [[DOTI05]]
; SMOLDCHECK-NEXT: [[DOTI18:%.*]] = and i1 [[DOTI14]], [[DOTI16]]
; SMOLDCHECK-NEXT: [[DOTUPTO012:%.*]] = insertelement <2 x i1> poison, i1 [[DOTI07]], i64 0
; SMOLDCHECK-NEXT: [[TMP0:%.*]] = insertelement <2 x i1> [[DOTUPTO012]], i1 [[DOTI18]], i64 1
; SMOLDCHECK-NEXT: ret <2 x i1> [[TMP0]]
;
entry:
%0 = call <2 x i1> @llvm.is.fpclass.v2f16(<2 x half> %a, i32 264)
ret <2 x i1> %0
}

declare i1 @llvm.is.fpclass.f32(float, i32 immarg)
declare <2 x i1> @llvm.is.fpclass.v2f32(<2 x float>, i32 immarg)