[DirectX] Add isinf f16 emulation for SM6.8 and lower #156932

farzonl · 2025-09-04T17:20:29Z

fixes #156068

We needed to add a new sub arch to the target tripple so we can test that emulation does not happen when targeting SM6.9
The HLSL toolchain needed to be updated to handle the conversion of strings to enums for the new sub arch.
The emulation is done in DXILIntrinsicExpansion.cpp and needs to be able to convert both llvm.is.fpclass and lvm.dx.isinf to the proper emulation
test updates in TargetParser/TripleTest.cpp, isinf.ll, is_fpclass.ll, and DXCModeTest.cpp

llvmbot · 2025-09-04T17:20:59Z

@llvm/pr-subscribers-clang
@llvm/pr-subscribers-backend-directx

@llvm/pr-subscribers-clang-driver

Author: Farzon Lotfi (farzonl)

Changes

fixes #156068

We needed to add a new sub arch to the target tripple so we can test that emulation does not happen when targeting SM6.9
The HLSL toolchain needed to be updated to handle the conversion of strings to enums for the new sub arch.
The emulation is done in DXILIntrinsicExpansion.cpp and needs to be able to convert both llvm.is.fpclass and lvm.dx.isinf to the proper emulation
test updates in TargetParser/TripleTest.cpp, isinf.ll, and is_fpclass.ll

Full diff: https://github.com/llvm/llvm-project/pull/156932.diff

7 Files Affected:

(modified) clang/lib/Driver/ToolChains/HLSL.cpp (+3)
(modified) llvm/include/llvm/TargetParser/Triple.h (+2-1)
(modified) llvm/lib/Target/DirectX/DXILIntrinsicExpansion.cpp (+42-1)
(modified) llvm/lib/TargetParser/Triple.cpp (+8-1)
(modified) llvm/test/CodeGen/DirectX/is_fpclass.ll (+19-2)
(modified) llvm/test/CodeGen/DirectX/isinf.ll (+37-6)
(modified) llvm/unittests/TargetParser/TripleTest.cpp (+13)

diff --git a/clang/lib/Driver/ToolChains/HLSL.cpp b/clang/lib/Driver/ToolChains/HLSL.cpp
index 660661945d62a..559af32dc3808 100644
--- a/clang/lib/Driver/ToolChains/HLSL.cpp
+++ b/clang/lib/Driver/ToolChains/HLSL.cpp
@@ -132,6 +132,9 @@ std::optional<std::string> tryParseProfile(StringRef Profile) {
   case 8:
     SubArch = llvm::Triple::DXILSubArch_v1_8;
     break;
+  case 9:
+    SubArch = llvm::Triple::DXILSubArch_v1_9;
+    break;
   case OfflineLibMinor:
     // Always consider minor version x as the latest supported DXIL version
     SubArch = llvm::Triple::LatestDXILSubArch;
diff --git a/llvm/include/llvm/TargetParser/Triple.h b/llvm/include/llvm/TargetParser/Triple.h
index f85984ed4f328..8e12c6852075d 100644
--- a/llvm/include/llvm/TargetParser/Triple.h
+++ b/llvm/include/llvm/TargetParser/Triple.h
@@ -180,7 +180,8 @@ class Triple {
     DXILSubArch_v1_6,
     DXILSubArch_v1_7,
     DXILSubArch_v1_8,
-    LatestDXILSubArch = DXILSubArch_v1_8,
+    DXILSubArch_v1_9,
+    LatestDXILSubArch = DXILSubArch_v1_9,
   };
   enum VendorType {
     UnknownVendor,
diff --git a/llvm/lib/Target/DirectX/DXILIntrinsicExpansion.cpp b/llvm/lib/Target/DirectX/DXILIntrinsicExpansion.cpp
index ee1db54446cb8..7966e3f1d6f3d 100644
--- a/llvm/lib/Target/DirectX/DXILIntrinsicExpansion.cpp
+++ b/llvm/lib/Target/DirectX/DXILIntrinsicExpansion.cpp
@@ -51,6 +51,42 @@ static bool resourceAccessNeeds64BitExpansion(Module *M, Type *OverloadTy,
   return ScalarTy->isDoubleTy() || ScalarTy->isIntegerTy(64);
 }
 
+  static Value* expand16BitIsInf(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->isHalfTy() ||
+      (ValTy->isVectorTy() &&
+       cast<FixedVectorType>(ValTy)->getElementType()->isHalfTy())))
+        return nullptr;
+
+    IRBuilder<> Builder(Orig);
+    Type *IType = Type::getInt16Ty(M->getContext());
+    Constant *PosInf = ValTy->isVectorTy()
+                       ? ConstantVector::getSplat(
+                             ElementCount::getFixed(
+                                 cast<FixedVectorType>(ValTy)->getNumElements()),
+                             ConstantInt::get(IType, 0x7c00))
+                       : ConstantInt::get(IType, 0x7c00);
+
+    Constant *NegInf = ValTy->isVectorTy()
+                       ? ConstantVector::getSplat(
+                             ElementCount::getFixed(
+                                 cast<FixedVectorType>(ValTy)->getNumElements()),
+                             ConstantInt::get(IType, 0xfc00))
+                       : ConstantInt::get(IType, 0xfc00);
+
+
+    Value *IVal = Builder.CreateBitCast(Val, PosInf->getType());
+    Value *B1 = Builder.CreateICmpEQ(IVal, PosInf);
+    Value *B2 = Builder.CreateICmpEQ(IVal, NegInf);
+    Value *B3 = Builder.CreateOr(B1, B2);
+    return B3;
+  }
+
 static bool isIntrinsicExpansion(Function &F) {
   switch (F.getIntrinsicID()) {
   case Intrinsic::abs:
@@ -68,6 +104,7 @@ static bool isIntrinsicExpansion(Function &F) {
   case Intrinsic::dx_sclamp:
   case Intrinsic::dx_nclamp:
   case Intrinsic::dx_degrees:
+  case Intrinsic::dx_isinf:
   case Intrinsic::dx_lerp:
   case Intrinsic::dx_normalize:
   case Intrinsic::dx_fdot:
@@ -301,9 +338,10 @@ static Value *expandIsFPClass(CallInst *Orig) {
   auto *TCI = dyn_cast<ConstantInt>(T);
 
   // These FPClassTest cases have DXIL opcodes, so they will be handled in
-  // DXIL Op Lowering instead.
+  // DXIL Op Lowering instead for all non f16 cases.
   switch (TCI->getZExtValue()) {
   case FPClassTest::fcInf:
+    return expand16BitIsInf(Orig);
   case FPClassTest::fcNan:
   case FPClassTest::fcNormal:
   case FPClassTest::fcFinite:
@@ -873,6 +911,9 @@ static bool expandIntrinsic(Function &F, CallInst *Orig) {
   case Intrinsic::dx_degrees:
     Result = expandDegreesIntrinsic(Orig);
     break;
+  case Intrinsic::dx_isinf:
+    Result = expand16BitIsInf(Orig);
+    break;
   case Intrinsic::dx_lerp:
     Result = expandLerpIntrinsic(Orig);
     break;
diff --git a/llvm/lib/TargetParser/Triple.cpp b/llvm/lib/TargetParser/Triple.cpp
index ec15f235b8624..2ee27ba4a7de4 100644
--- a/llvm/lib/TargetParser/Triple.cpp
+++ b/llvm/lib/TargetParser/Triple.cpp
@@ -158,6 +158,8 @@ StringRef Triple::getArchName(ArchType Kind, SubArchType SubArch) {
       return "dxilv1.7";
     case Triple::DXILSubArch_v1_8:
       return "dxilv1.8";
+    case Triple::DXILSubArch_v1_9:
+      return "dxilv1.9";
     default:
       break;
     }
@@ -650,6 +652,8 @@ static Triple::ArchType parseArch(StringRef ArchName) {
                 .Cases("dxil", "dxilv1.0", "dxilv1.1", "dxilv1.2", "dxilv1.3",
                        "dxilv1.4", "dxilv1.5", "dxilv1.6", "dxilv1.7",
                        "dxilv1.8", Triple::dxil)
+                //Note: Cases has max limit of 10.
+                .Case("dxilv1.9", Triple::dxil)
                 .Case("xtensa", Triple::xtensa)
                 .Default(Triple::UnknownArch);
 
@@ -842,6 +846,7 @@ static Triple::SubArchType parseSubArch(StringRef SubArchName) {
         .EndsWith("v1.6", Triple::DXILSubArch_v1_6)
         .EndsWith("v1.7", Triple::DXILSubArch_v1_7)
         .EndsWith("v1.8", Triple::DXILSubArch_v1_8)
+        .EndsWith("v1.9", Triple::DXILSubArch_v1_9)
         .Default(Triple::NoSubArch);
 
   StringRef ARMSubArch = ARM::getCanonicalArchName(SubArchName);
@@ -1111,7 +1116,7 @@ static StringRef getDXILArchNameFromShaderModel(StringRef ShaderModelStr) {
   VersionTuple Ver =
       parseVersionFromName(ShaderModelStr.drop_front(strlen("shadermodel")));
   // Default DXIL minor version when Shader Model version is anything other
-  // than 6.[0...8] or 6.x (which translates to latest current SM version)
+  // than 6.[0...9] or 6.x (which translates to latest current SM version)
   const unsigned SMMajor = 6;
   if (!Ver.empty()) {
     if (Ver.getMajor() == SMMajor) {
@@ -1135,6 +1140,8 @@ static StringRef getDXILArchNameFromShaderModel(StringRef ShaderModelStr) {
           return Triple::getArchName(Triple::dxil, Triple::DXILSubArch_v1_7);
         case 8:
           return Triple::getArchName(Triple::dxil, Triple::DXILSubArch_v1_8);
+        case 9:
+          return Triple::getArchName(Triple::dxil, Triple::DXILSubArch_v1_9);
         default:
           report_fatal_error("Unsupported Shader Model version", false);
         }
diff --git a/llvm/test/CodeGen/DirectX/is_fpclass.ll b/llvm/test/CodeGen/DirectX/is_fpclass.ll
index a628096aacd7d..1796e8bd794d8 100644
--- a/llvm/test/CodeGen/DirectX/is_fpclass.ll
+++ b/llvm/test/CodeGen/DirectX/is_fpclass.ll
@@ -1,5 +1,5 @@
-; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
-; RUN: opt -S -dxil-intrinsic-expansion -scalarizer -dxil-op-lower -mtriple=dxil-pc-shadermodel6.3-library %s | FileCheck %s
+; RUN: opt -S -dxil-intrinsic-expansion -scalarizer -dxil-op-lower -mtriple=dxil-pc-shadermodel6.9-library %s | FileCheck %s --check-prefixes=CHECK,SM69CHECK
+; RUN: opt -S -dxil-intrinsic-expansion -scalarizer -dxil-op-lower -mtriple=dxil-pc-shadermodel6.8-library %s | FileCheck %s --check-prefixes=CHECK,SMOLDCHECK
 
 
 define noundef i1 @isnegzero(float noundef %a) {
@@ -75,6 +75,23 @@ entry:
   ret i1 %0
 }
 
+define noundef i1 @isinfh(half noundef %a) {
+; CHECK-LABEL: define noundef i1 @isinfh(
+; 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: [[CMPHIGH:%.*]] = icmp eq i16 [[BITCAST]], 31744
+; SMOLDCHECK-NEXT: [[CMPLOW:%.*]] = icmp eq i16 [[BITCAST]], -1024
+; SMOLDCHECK-NEXT: [[OR:%.*]] = or i1 [[CMPHIGH]], [[CMPLOW]]
+; SMOLDCHECK-NEXT:   ret i1 [[OR]]
+; SM69CHECK-NEXT:    ret i1 [[ISINF]]
+;
+entry:
+  %0 = call i1 @llvm.is.fpclass.f16(half %a, i32 516)
+  ret i1 %0
+}
+
 define noundef <2 x i1> @isinfv2(<2 x float> noundef %a) {
 ; CHECK-LABEL: define noundef <2 x i1> @isinfv2(
 ; CHECK-SAME: <2 x float> noundef [[A:%.*]]) {
diff --git a/llvm/test/CodeGen/DirectX/isinf.ll b/llvm/test/CodeGen/DirectX/isinf.ll
index 461553b533ae1..bf31363ee114c 100644
--- a/llvm/test/CodeGen/DirectX/isinf.ll
+++ b/llvm/test/CodeGen/DirectX/isinf.ll
@@ -1,4 +1,5 @@
-; RUN: opt -S -scalarizer -dxil-op-lower -mtriple=dxil-pc-shadermodel6.3-library %s | FileCheck %s
+; RUN: opt -S -dxil-intrinsic-expansion -scalarizer -dxil-op-lower -mtriple=dxil-pc-shadermodel6.9-library %s | FileCheck %s --check-prefixes=CHECK,SM69CHECK
+; RUN: opt -S -dxil-intrinsic-expansion -scalarizer -dxil-op-lower -mtriple=dxil-pc-shadermodel6.8-library %s | FileCheck %s --check-prefixes=CHECK,SMOLDCHECK
 
 ; Make sure dxil operation function calls for isinf are generated for float and half.
 
@@ -11,17 +12,47 @@ entry:
 
 define noundef i1 @isinf_half(half noundef %a) {
 entry:
-  ; CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half %{{.*}}) #[[#ATTR]]
+  ; SM69CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half %{{.*}}) #[[#ATTR]]
+  ; SMOLDCHECK: [[BITCAST:%.*]] = bitcast half %a to i16
+  ; SMOLDCHECK: [[CMPHIGH:%.*]] = icmp eq i16 [[BITCAST]], 31744
+  ; SMOLDCHECK: [[CMPLOW:%.*]] = icmp eq i16 [[BITCAST]], -1024
+  ; SMOLDCHECK: [[OR:%.*]] = or i1 [[CMPHIGH]], [[CMPLOW]]
   %dx.isinf = call i1 @llvm.dx.isinf.f16(half %a)
   ret i1 %dx.isinf
 }
 
 define noundef <4 x i1> @isinf_half4(<4 x half> noundef %p0) {
 entry:
-  ; CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half
-  ; CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half
-  ; CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half
-  ; CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half
+  ; SM69CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half
+  ; SM69CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half
+  ; SM69CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half
+  ; SM69CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half
+
+  ; SMOLDCHECK: [[ee0:%.*]] = extractelement <4 x half> %p0, i64 0
+  ; SMOLDCHECK: [[BITCAST0:%.*]] = bitcast half [[ee0]] to i16
+  ; SMOLDCHECK: [[ee1:%.*]] = extractelement <4 x half> %p0, i64 1
+  ; SMOLDCHECK: [[BITCAST1:%.*]] = bitcast half [[ee1]] to i16
+  ; SMOLDCHECK:[[ee2:%.*]] = extractelement <4 x half> %p0, i64 2
+  ; SMOLDCHECK: [[BITCAST2:%.*]] = bitcast half [[ee2]] to i16
+  ; SMOLDCHECK: [[ee3:%.*]] = extractelement <4 x half> %p0, i64 3
+  ; SMOLDCHECK: [[BITCAST3:%.*]] = bitcast half [[ee3]] to i16
+  ; SMOLDCHECK: [[ICMPHIGH0:%.*]] = icmp eq i16 [[BITCAST0]], 31744
+  ; SMOLDCHECK: [[ICMPHIGH1:%.*]] = icmp eq i16 [[BITCAST1]], 31744
+  ; SMOLDCHECK: [[ICMPHIGH2:%.*]] = icmp eq i16 [[BITCAST2]], 31744
+  ; SMOLDCHECK: [[ICMPHIGH3:%.*]] = icmp eq i16 [[BITCAST3]], 31744
+  ; SMOLDCHECK: [[ICMPLOW0:%.*]] = icmp eq i16 [[BITCAST0]], -1024
+  ; SMOLDCHECK: [[ICMPLOW1:%.*]] = icmp eq i16 [[BITCAST1]], -1024
+  ; SMOLDCHECK: [[ICMPLOW2:%.*]] = icmp eq i16 [[BITCAST2]], -1024
+  ; SMOLDCHECK: [[ICMPLOW3:%.*]] = icmp eq i16 [[BITCAST3]], -1024
+  ; SMOLDCHECK: [[OR0:%.*]] = or i1 [[ICMPHIGH0]], [[ICMPLOW0]]
+  ; SMOLDCHECK: [[OR1:%.*]] = or i1 [[ICMPHIGH1]], [[ICMPLOW1]]
+  ; SMOLDCHECK: [[OR2:%.*]] = or i1 [[ICMPHIGH2]], [[ICMPLOW2]]
+  ; SMOLDCHECK: [[OR3:%.*]] = or i1 [[ICMPHIGH3]], [[ICMPLOW3]]
+  ; SMOLDCHECK: %.upto019 = insertelement <4 x i1> poison, i1 [[OR0]], i64 0
+  ; SMOLDCHECK: %.upto120 = insertelement <4 x i1> %.upto019, i1 [[OR1]], i64 1
+  ; SMOLDCHECK: %.upto221 = insertelement <4 x i1> %.upto120, i1 [[OR2]], i64 2
+  ; SMOLDCHECK: %0 = insertelement <4 x i1> %.upto221, i1 [[OR3]], i64 3
+
   %hlsl.isinf = call <4 x i1> @llvm.dx.isinf.v4f16(<4 x half> %p0)
   ret <4 x i1> %hlsl.isinf
 }
diff --git a/llvm/unittests/TargetParser/TripleTest.cpp b/llvm/unittests/TargetParser/TripleTest.cpp
index 7d07615d273d7..942912bcfe0e2 100644
--- a/llvm/unittests/TargetParser/TripleTest.cpp
+++ b/llvm/unittests/TargetParser/TripleTest.cpp
@@ -553,6 +553,13 @@ TEST(TripleTest, ParsedIDs) {
   EXPECT_EQ(Triple::ShaderModel, T.getOS());
   EXPECT_EQ(VersionTuple(1, 8), T.getDXILVersion());
 
+  T = Triple("dxilv1.9-unknown-shadermodel6.15-library");
+  EXPECT_EQ(Triple::dxil, T.getArch());
+  EXPECT_EQ(Triple::DXILSubArch_v1_9, T.getSubArch());
+  EXPECT_EQ(Triple::UnknownVendor, T.getVendor());
+  EXPECT_EQ(Triple::ShaderModel, T.getOS());
+  EXPECT_EQ(VersionTuple(1, 9), T.getDXILVersion());
+
   T = Triple("x86_64-unknown-fuchsia");
   EXPECT_EQ(Triple::x86_64, T.getArch());
   EXPECT_EQ(Triple::UnknownVendor, T.getVendor());
@@ -1270,6 +1277,12 @@ TEST(TripleTest, ParsedIDs) {
   EXPECT_EQ(Triple::UnknownVendor, T.getVendor());
   EXPECT_EQ(Triple::UnknownOS, T.getOS());
 
+  T = Triple("dxilv1.9-unknown-unknown");
+  EXPECT_EQ(Triple::dxil, T.getArch());
+  EXPECT_EQ(Triple::DXILSubArch_v1_9, T.getSubArch());
+  EXPECT_EQ(Triple::UnknownVendor, T.getVendor());
+  EXPECT_EQ(Triple::UnknownOS, T.getOS());
+
   // Check specification of unknown SubArch results in
   // unknown architecture.
   T = Triple("dxilv1.999-unknown-unknown");

llvmbot · 2025-09-04T17:21:00Z

@llvm/pr-subscribers-hlsl

Author: Farzon Lotfi (farzonl)

Changes

fixes #156068

We needed to add a new sub arch to the target tripple so we can test that emulation does not happen when targeting SM6.9
The HLSL toolchain needed to be updated to handle the conversion of strings to enums for the new sub arch.
The emulation is done in DXILIntrinsicExpansion.cpp and needs to be able to convert both llvm.is.fpclass and lvm.dx.isinf to the proper emulation
test updates in TargetParser/TripleTest.cpp, isinf.ll, and is_fpclass.ll

Full diff: https://github.com/llvm/llvm-project/pull/156932.diff

7 Files Affected:

(modified) clang/lib/Driver/ToolChains/HLSL.cpp (+3)
(modified) llvm/include/llvm/TargetParser/Triple.h (+2-1)
(modified) llvm/lib/Target/DirectX/DXILIntrinsicExpansion.cpp (+42-1)
(modified) llvm/lib/TargetParser/Triple.cpp (+8-1)
(modified) llvm/test/CodeGen/DirectX/is_fpclass.ll (+19-2)
(modified) llvm/test/CodeGen/DirectX/isinf.ll (+37-6)
(modified) llvm/unittests/TargetParser/TripleTest.cpp (+13)

diff --git a/clang/lib/Driver/ToolChains/HLSL.cpp b/clang/lib/Driver/ToolChains/HLSL.cpp
index 660661945d62a..559af32dc3808 100644
--- a/clang/lib/Driver/ToolChains/HLSL.cpp
+++ b/clang/lib/Driver/ToolChains/HLSL.cpp
@@ -132,6 +132,9 @@ std::optional<std::string> tryParseProfile(StringRef Profile) {
   case 8:
     SubArch = llvm::Triple::DXILSubArch_v1_8;
     break;
+  case 9:
+    SubArch = llvm::Triple::DXILSubArch_v1_9;
+    break;
   case OfflineLibMinor:
     // Always consider minor version x as the latest supported DXIL version
     SubArch = llvm::Triple::LatestDXILSubArch;
diff --git a/llvm/include/llvm/TargetParser/Triple.h b/llvm/include/llvm/TargetParser/Triple.h
index f85984ed4f328..8e12c6852075d 100644
--- a/llvm/include/llvm/TargetParser/Triple.h
+++ b/llvm/include/llvm/TargetParser/Triple.h
@@ -180,7 +180,8 @@ class Triple {
     DXILSubArch_v1_6,
     DXILSubArch_v1_7,
     DXILSubArch_v1_8,
-    LatestDXILSubArch = DXILSubArch_v1_8,
+    DXILSubArch_v1_9,
+    LatestDXILSubArch = DXILSubArch_v1_9,
   };
   enum VendorType {
     UnknownVendor,
diff --git a/llvm/lib/Target/DirectX/DXILIntrinsicExpansion.cpp b/llvm/lib/Target/DirectX/DXILIntrinsicExpansion.cpp
index ee1db54446cb8..7966e3f1d6f3d 100644
--- a/llvm/lib/Target/DirectX/DXILIntrinsicExpansion.cpp
+++ b/llvm/lib/Target/DirectX/DXILIntrinsicExpansion.cpp
@@ -51,6 +51,42 @@ static bool resourceAccessNeeds64BitExpansion(Module *M, Type *OverloadTy,
   return ScalarTy->isDoubleTy() || ScalarTy->isIntegerTy(64);
 }
 
+  static Value* expand16BitIsInf(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->isHalfTy() ||
+      (ValTy->isVectorTy() &&
+       cast<FixedVectorType>(ValTy)->getElementType()->isHalfTy())))
+        return nullptr;
+
+    IRBuilder<> Builder(Orig);
+    Type *IType = Type::getInt16Ty(M->getContext());
+    Constant *PosInf = ValTy->isVectorTy()
+                       ? ConstantVector::getSplat(
+                             ElementCount::getFixed(
+                                 cast<FixedVectorType>(ValTy)->getNumElements()),
+                             ConstantInt::get(IType, 0x7c00))
+                       : ConstantInt::get(IType, 0x7c00);
+
+    Constant *NegInf = ValTy->isVectorTy()
+                       ? ConstantVector::getSplat(
+                             ElementCount::getFixed(
+                                 cast<FixedVectorType>(ValTy)->getNumElements()),
+                             ConstantInt::get(IType, 0xfc00))
+                       : ConstantInt::get(IType, 0xfc00);
+
+
+    Value *IVal = Builder.CreateBitCast(Val, PosInf->getType());
+    Value *B1 = Builder.CreateICmpEQ(IVal, PosInf);
+    Value *B2 = Builder.CreateICmpEQ(IVal, NegInf);
+    Value *B3 = Builder.CreateOr(B1, B2);
+    return B3;
+  }
+
 static bool isIntrinsicExpansion(Function &F) {
   switch (F.getIntrinsicID()) {
   case Intrinsic::abs:
@@ -68,6 +104,7 @@ static bool isIntrinsicExpansion(Function &F) {
   case Intrinsic::dx_sclamp:
   case Intrinsic::dx_nclamp:
   case Intrinsic::dx_degrees:
+  case Intrinsic::dx_isinf:
   case Intrinsic::dx_lerp:
   case Intrinsic::dx_normalize:
   case Intrinsic::dx_fdot:
@@ -301,9 +338,10 @@ static Value *expandIsFPClass(CallInst *Orig) {
   auto *TCI = dyn_cast<ConstantInt>(T);
 
   // These FPClassTest cases have DXIL opcodes, so they will be handled in
-  // DXIL Op Lowering instead.
+  // DXIL Op Lowering instead for all non f16 cases.
   switch (TCI->getZExtValue()) {
   case FPClassTest::fcInf:
+    return expand16BitIsInf(Orig);
   case FPClassTest::fcNan:
   case FPClassTest::fcNormal:
   case FPClassTest::fcFinite:
@@ -873,6 +911,9 @@ static bool expandIntrinsic(Function &F, CallInst *Orig) {
   case Intrinsic::dx_degrees:
     Result = expandDegreesIntrinsic(Orig);
     break;
+  case Intrinsic::dx_isinf:
+    Result = expand16BitIsInf(Orig);
+    break;
   case Intrinsic::dx_lerp:
     Result = expandLerpIntrinsic(Orig);
     break;
diff --git a/llvm/lib/TargetParser/Triple.cpp b/llvm/lib/TargetParser/Triple.cpp
index ec15f235b8624..2ee27ba4a7de4 100644
--- a/llvm/lib/TargetParser/Triple.cpp
+++ b/llvm/lib/TargetParser/Triple.cpp
@@ -158,6 +158,8 @@ StringRef Triple::getArchName(ArchType Kind, SubArchType SubArch) {
       return "dxilv1.7";
     case Triple::DXILSubArch_v1_8:
       return "dxilv1.8";
+    case Triple::DXILSubArch_v1_9:
+      return "dxilv1.9";
     default:
       break;
     }
@@ -650,6 +652,8 @@ static Triple::ArchType parseArch(StringRef ArchName) {
                 .Cases("dxil", "dxilv1.0", "dxilv1.1", "dxilv1.2", "dxilv1.3",
                        "dxilv1.4", "dxilv1.5", "dxilv1.6", "dxilv1.7",
                        "dxilv1.8", Triple::dxil)
+                //Note: Cases has max limit of 10.
+                .Case("dxilv1.9", Triple::dxil)
                 .Case("xtensa", Triple::xtensa)
                 .Default(Triple::UnknownArch);
 
@@ -842,6 +846,7 @@ static Triple::SubArchType parseSubArch(StringRef SubArchName) {
         .EndsWith("v1.6", Triple::DXILSubArch_v1_6)
         .EndsWith("v1.7", Triple::DXILSubArch_v1_7)
         .EndsWith("v1.8", Triple::DXILSubArch_v1_8)
+        .EndsWith("v1.9", Triple::DXILSubArch_v1_9)
         .Default(Triple::NoSubArch);
 
   StringRef ARMSubArch = ARM::getCanonicalArchName(SubArchName);
@@ -1111,7 +1116,7 @@ static StringRef getDXILArchNameFromShaderModel(StringRef ShaderModelStr) {
   VersionTuple Ver =
       parseVersionFromName(ShaderModelStr.drop_front(strlen("shadermodel")));
   // Default DXIL minor version when Shader Model version is anything other
-  // than 6.[0...8] or 6.x (which translates to latest current SM version)
+  // than 6.[0...9] or 6.x (which translates to latest current SM version)
   const unsigned SMMajor = 6;
   if (!Ver.empty()) {
     if (Ver.getMajor() == SMMajor) {
@@ -1135,6 +1140,8 @@ static StringRef getDXILArchNameFromShaderModel(StringRef ShaderModelStr) {
           return Triple::getArchName(Triple::dxil, Triple::DXILSubArch_v1_7);
         case 8:
           return Triple::getArchName(Triple::dxil, Triple::DXILSubArch_v1_8);
+        case 9:
+          return Triple::getArchName(Triple::dxil, Triple::DXILSubArch_v1_9);
         default:
           report_fatal_error("Unsupported Shader Model version", false);
         }
diff --git a/llvm/test/CodeGen/DirectX/is_fpclass.ll b/llvm/test/CodeGen/DirectX/is_fpclass.ll
index a628096aacd7d..1796e8bd794d8 100644
--- a/llvm/test/CodeGen/DirectX/is_fpclass.ll
+++ b/llvm/test/CodeGen/DirectX/is_fpclass.ll
@@ -1,5 +1,5 @@
-; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
-; RUN: opt -S -dxil-intrinsic-expansion -scalarizer -dxil-op-lower -mtriple=dxil-pc-shadermodel6.3-library %s | FileCheck %s
+; RUN: opt -S -dxil-intrinsic-expansion -scalarizer -dxil-op-lower -mtriple=dxil-pc-shadermodel6.9-library %s | FileCheck %s --check-prefixes=CHECK,SM69CHECK
+; RUN: opt -S -dxil-intrinsic-expansion -scalarizer -dxil-op-lower -mtriple=dxil-pc-shadermodel6.8-library %s | FileCheck %s --check-prefixes=CHECK,SMOLDCHECK
 
 
 define noundef i1 @isnegzero(float noundef %a) {
@@ -75,6 +75,23 @@ entry:
   ret i1 %0
 }
 
+define noundef i1 @isinfh(half noundef %a) {
+; CHECK-LABEL: define noundef i1 @isinfh(
+; 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: [[CMPHIGH:%.*]] = icmp eq i16 [[BITCAST]], 31744
+; SMOLDCHECK-NEXT: [[CMPLOW:%.*]] = icmp eq i16 [[BITCAST]], -1024
+; SMOLDCHECK-NEXT: [[OR:%.*]] = or i1 [[CMPHIGH]], [[CMPLOW]]
+; SMOLDCHECK-NEXT:   ret i1 [[OR]]
+; SM69CHECK-NEXT:    ret i1 [[ISINF]]
+;
+entry:
+  %0 = call i1 @llvm.is.fpclass.f16(half %a, i32 516)
+  ret i1 %0
+}
+
 define noundef <2 x i1> @isinfv2(<2 x float> noundef %a) {
 ; CHECK-LABEL: define noundef <2 x i1> @isinfv2(
 ; CHECK-SAME: <2 x float> noundef [[A:%.*]]) {
diff --git a/llvm/test/CodeGen/DirectX/isinf.ll b/llvm/test/CodeGen/DirectX/isinf.ll
index 461553b533ae1..bf31363ee114c 100644
--- a/llvm/test/CodeGen/DirectX/isinf.ll
+++ b/llvm/test/CodeGen/DirectX/isinf.ll
@@ -1,4 +1,5 @@
-; RUN: opt -S -scalarizer -dxil-op-lower -mtriple=dxil-pc-shadermodel6.3-library %s | FileCheck %s
+; RUN: opt -S -dxil-intrinsic-expansion -scalarizer -dxil-op-lower -mtriple=dxil-pc-shadermodel6.9-library %s | FileCheck %s --check-prefixes=CHECK,SM69CHECK
+; RUN: opt -S -dxil-intrinsic-expansion -scalarizer -dxil-op-lower -mtriple=dxil-pc-shadermodel6.8-library %s | FileCheck %s --check-prefixes=CHECK,SMOLDCHECK
 
 ; Make sure dxil operation function calls for isinf are generated for float and half.
 
@@ -11,17 +12,47 @@ entry:
 
 define noundef i1 @isinf_half(half noundef %a) {
 entry:
-  ; CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half %{{.*}}) #[[#ATTR]]
+  ; SM69CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half %{{.*}}) #[[#ATTR]]
+  ; SMOLDCHECK: [[BITCAST:%.*]] = bitcast half %a to i16
+  ; SMOLDCHECK: [[CMPHIGH:%.*]] = icmp eq i16 [[BITCAST]], 31744
+  ; SMOLDCHECK: [[CMPLOW:%.*]] = icmp eq i16 [[BITCAST]], -1024
+  ; SMOLDCHECK: [[OR:%.*]] = or i1 [[CMPHIGH]], [[CMPLOW]]
   %dx.isinf = call i1 @llvm.dx.isinf.f16(half %a)
   ret i1 %dx.isinf
 }
 
 define noundef <4 x i1> @isinf_half4(<4 x half> noundef %p0) {
 entry:
-  ; CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half
-  ; CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half
-  ; CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half
-  ; CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half
+  ; SM69CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half
+  ; SM69CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half
+  ; SM69CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half
+  ; SM69CHECK: call i1 @dx.op.isSpecialFloat.f16(i32 9, half
+
+  ; SMOLDCHECK: [[ee0:%.*]] = extractelement <4 x half> %p0, i64 0
+  ; SMOLDCHECK: [[BITCAST0:%.*]] = bitcast half [[ee0]] to i16
+  ; SMOLDCHECK: [[ee1:%.*]] = extractelement <4 x half> %p0, i64 1
+  ; SMOLDCHECK: [[BITCAST1:%.*]] = bitcast half [[ee1]] to i16
+  ; SMOLDCHECK:[[ee2:%.*]] = extractelement <4 x half> %p0, i64 2
+  ; SMOLDCHECK: [[BITCAST2:%.*]] = bitcast half [[ee2]] to i16
+  ; SMOLDCHECK: [[ee3:%.*]] = extractelement <4 x half> %p0, i64 3
+  ; SMOLDCHECK: [[BITCAST3:%.*]] = bitcast half [[ee3]] to i16
+  ; SMOLDCHECK: [[ICMPHIGH0:%.*]] = icmp eq i16 [[BITCAST0]], 31744
+  ; SMOLDCHECK: [[ICMPHIGH1:%.*]] = icmp eq i16 [[BITCAST1]], 31744
+  ; SMOLDCHECK: [[ICMPHIGH2:%.*]] = icmp eq i16 [[BITCAST2]], 31744
+  ; SMOLDCHECK: [[ICMPHIGH3:%.*]] = icmp eq i16 [[BITCAST3]], 31744
+  ; SMOLDCHECK: [[ICMPLOW0:%.*]] = icmp eq i16 [[BITCAST0]], -1024
+  ; SMOLDCHECK: [[ICMPLOW1:%.*]] = icmp eq i16 [[BITCAST1]], -1024
+  ; SMOLDCHECK: [[ICMPLOW2:%.*]] = icmp eq i16 [[BITCAST2]], -1024
+  ; SMOLDCHECK: [[ICMPLOW3:%.*]] = icmp eq i16 [[BITCAST3]], -1024
+  ; SMOLDCHECK: [[OR0:%.*]] = or i1 [[ICMPHIGH0]], [[ICMPLOW0]]
+  ; SMOLDCHECK: [[OR1:%.*]] = or i1 [[ICMPHIGH1]], [[ICMPLOW1]]
+  ; SMOLDCHECK: [[OR2:%.*]] = or i1 [[ICMPHIGH2]], [[ICMPLOW2]]
+  ; SMOLDCHECK: [[OR3:%.*]] = or i1 [[ICMPHIGH3]], [[ICMPLOW3]]
+  ; SMOLDCHECK: %.upto019 = insertelement <4 x i1> poison, i1 [[OR0]], i64 0
+  ; SMOLDCHECK: %.upto120 = insertelement <4 x i1> %.upto019, i1 [[OR1]], i64 1
+  ; SMOLDCHECK: %.upto221 = insertelement <4 x i1> %.upto120, i1 [[OR2]], i64 2
+  ; SMOLDCHECK: %0 = insertelement <4 x i1> %.upto221, i1 [[OR3]], i64 3
+
   %hlsl.isinf = call <4 x i1> @llvm.dx.isinf.v4f16(<4 x half> %p0)
   ret <4 x i1> %hlsl.isinf
 }
diff --git a/llvm/unittests/TargetParser/TripleTest.cpp b/llvm/unittests/TargetParser/TripleTest.cpp
index 7d07615d273d7..942912bcfe0e2 100644
--- a/llvm/unittests/TargetParser/TripleTest.cpp
+++ b/llvm/unittests/TargetParser/TripleTest.cpp
@@ -553,6 +553,13 @@ TEST(TripleTest, ParsedIDs) {
   EXPECT_EQ(Triple::ShaderModel, T.getOS());
   EXPECT_EQ(VersionTuple(1, 8), T.getDXILVersion());
 
+  T = Triple("dxilv1.9-unknown-shadermodel6.15-library");
+  EXPECT_EQ(Triple::dxil, T.getArch());
+  EXPECT_EQ(Triple::DXILSubArch_v1_9, T.getSubArch());
+  EXPECT_EQ(Triple::UnknownVendor, T.getVendor());
+  EXPECT_EQ(Triple::ShaderModel, T.getOS());
+  EXPECT_EQ(VersionTuple(1, 9), T.getDXILVersion());
+
   T = Triple("x86_64-unknown-fuchsia");
   EXPECT_EQ(Triple::x86_64, T.getArch());
   EXPECT_EQ(Triple::UnknownVendor, T.getVendor());
@@ -1270,6 +1277,12 @@ TEST(TripleTest, ParsedIDs) {
   EXPECT_EQ(Triple::UnknownVendor, T.getVendor());
   EXPECT_EQ(Triple::UnknownOS, T.getOS());
 
+  T = Triple("dxilv1.9-unknown-unknown");
+  EXPECT_EQ(Triple::dxil, T.getArch());
+  EXPECT_EQ(Triple::DXILSubArch_v1_9, T.getSubArch());
+  EXPECT_EQ(Triple::UnknownVendor, T.getVendor());
+  EXPECT_EQ(Triple::UnknownOS, T.getOS());
+
   // Check specification of unknown SubArch results in
   // unknown architecture.
   T = Triple("dxilv1.999-unknown-unknown");

github-actions · 2025-09-04T17:23:41Z

✅ With the latest revision this PR passed the C/C++ code formatter.

fixes llvm#156068 - We needed to add a new sub arch to the target tripple so we can test that emulation does not happen when targeting SM6.9 - The HLSL toolchain needed to be updated to handle the conversion of strings to enums for the new sub arch. - The emulation is done in DXILIntrinsicExpansion.cpp and needs to be able to convert both llvm.is.fpclass and lvm.dx.isinf to the proper emulation - test updates in TargetParser/TripleTest.cpp, isinf.ll, and is_fpclass.ll

llvmbot added clang Clang issues not falling into any other category clang:driver 'clang' and 'clang++' user-facing binaries. Not 'clang-cl' backend:DirectX HLSL HLSL Language Support labels Sep 4, 2025

farzonl force-pushed the feature/isinf_f16_emulation_issue-156068 branch from dcc6ae9 to 8c31865 Compare September 4, 2025 17:24

farzonl added 2 commits September 4, 2025 15:12

update test case.

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update unit test

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