[clang] [llvm] [SPIRV] Add PreLegalizer pattern matching for `faceforward` (PR #139959)
Kaitlin Peng via cfe-commits
cfe-commits at lists.llvm.org
Fri May 16 16:51:47 PDT 2025
https://github.com/kmpeng updated https://github.com/llvm/llvm-project/pull/139959
>From be7df595c1df0f310a1941da3d3ac3529270241e Mon Sep 17 00:00:00 2001
From: kmpeng <kaitlinpeng at microsoft.com>
Date: Tue, 29 Apr 2025 16:46:08 -0700
Subject: [PATCH 1/5] WIP - debug `matchSelectToFaceForward`
---
.../lib/Headers/hlsl/hlsl_intrinsic_helpers.h | 9 +-
llvm/lib/Target/SPIRV/SPIRVCombine.td | 9 +-
.../SPIRV/SPIRVPreLegalizerCombiner.cpp | 100 ++++++++++++++++++
...egalizercombiner-select-to-faceforward.mir | 33 ++++++
.../SPIRV/hlsl-intrinsics/faceforward.ll | 44 ++------
5 files changed, 153 insertions(+), 42 deletions(-)
create mode 100644 llvm/test/CodeGen/SPIRV/GlobalISel/InstCombine/prelegalizercombiner-select-to-faceforward.mir
diff --git a/clang/lib/Headers/hlsl/hlsl_intrinsic_helpers.h b/clang/lib/Headers/hlsl/hlsl_intrinsic_helpers.h
index 4eb7b8f45c85a..68dc6d96f89c1 100644
--- a/clang/lib/Headers/hlsl/hlsl_intrinsic_helpers.h
+++ b/clang/lib/Headers/hlsl/hlsl_intrinsic_helpers.h
@@ -127,11 +127,12 @@ template <typename T> constexpr vector<T, 4> lit_impl(T NDotL, T NDotH, T M) {
}
template <typename T> constexpr T faceforward_impl(T N, T I, T Ng) {
-#if (__has_builtin(__builtin_spirv_faceforward))
- return __builtin_spirv_faceforward(N, I, Ng);
-#else
+// #if (__has_builtin(__builtin_spirv_faceforward))
+// return __builtin_spirv_faceforward(N, I, Ng);
+// #else
+// return select(dot(I, Ng) < 0, N, -N);
+// #endif
return select(dot(I, Ng) < 0, N, -N);
-#endif
}
template <typename T> constexpr T ldexp_impl(T X, T Exp) {
diff --git a/llvm/lib/Target/SPIRV/SPIRVCombine.td b/llvm/lib/Target/SPIRV/SPIRVCombine.td
index 6f726e024de52..78a57146e61d2 100644
--- a/llvm/lib/Target/SPIRV/SPIRVCombine.td
+++ b/llvm/lib/Target/SPIRV/SPIRVCombine.td
@@ -15,8 +15,15 @@ def vector_length_sub_to_distance_lowering : GICombineRule <
(apply [{ applySPIRVDistance(*${root}, MRI, B); }])
>;
+def vector_select_to_faceforward_lowering : GICombineRule <
+ (defs root:$root),
+ (match (wip_match_opcode G_SELECT):$root,
+ [{ return matchSelectToFaceForward(*${root}, MRI); }]),
+ (apply [{ applySPIRVFaceForward(*${root}, MRI, B); }])
+>;
+
def SPIRVPreLegalizerCombiner
: GICombiner<"SPIRVPreLegalizerCombinerImpl",
- [vector_length_sub_to_distance_lowering]> {
+ [vector_length_sub_to_distance_lowering, vector_select_to_faceforward_lowering]> {
let CombineAllMethodName = "tryCombineAllImpl";
}
diff --git a/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp b/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp
index c96ee6b02491a..d323453e68828 100644
--- a/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp
+++ b/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp
@@ -113,6 +113,106 @@ void applySPIRVDistance(MachineInstr &MI, MachineRegisterInfo &MRI,
SubInstr->eraseFromParent(); // remove FSUB instruction
}
+/// This match is part of a combine that
+/// rewrites select(fcmp(dot(I, Ng), 0), N, 0 - N) to faceforward(N, I, Ng)
+/// (vXf32 (g_select
+/// (g_fcmp
+/// (g_intrinsic dot(vXf32 I) (vXf32 Ng)
+/// 0)
+/// (vXf32 N)
+/// (vXf32 g_fsub (0) (vXf32 N))))
+/// ->
+/// (vXf32 (g_intrinsic faceforward
+/// (vXf32 N) (vXf32 I) (vXf32 Ng)))
+///
+bool matchSelectToFaceForward(MachineInstr &MI, MachineRegisterInfo &MRI) {
+ if (MI.getOpcode() != TargetOpcode::G_SELECT)
+ return false;
+
+ // Check if the condition is a comparison between a dot product and zero
+ Register CondReg = MI.getOperand(1).getReg();
+ MachineInstr *CondInstr = MRI.getVRegDef(CondReg);
+ if (!CondInstr || CondInstr->getOpcode() != TargetOpcode::G_FCMP)
+ return false;
+
+ if (!CondInstr->getOperand(2).getReg())
+ return false;
+ Register DotReg = CondInstr->getOperand(2).getReg();
+ MachineInstr *DotInstr = MRI.getVRegDef(DotReg);
+ // fmul?
+ if (DotInstr->getOpcode() != TargetOpcode::G_INTRINSIC || cast<GIntrinsic>(DotInstr)->getIntrinsicID() != Intrinsic::spv_fdot)
+ return false;
+ // // is using getImm() correct?
+ // if (!CondInstr->getOperand(3).isImm() ||
+ // CondInstr->getOperand(3).getImm() != 0)
+ // return false;
+
+ // // Check if the false operand is the negation of the true operand
+ // Register TrueReg = MI.getOperand(2).getReg();
+ // Register FalseReg = MI.getOperand(3).getReg();
+ // MachineInstr *FalseInstr = MRI.getVRegDef(FalseReg);
+ // // getImm() correct?
+ // if (FalseInstr->getOpcode() != TargetOpcode::G_FSUB ||
+ // FalseInstr->getOperand(1).getImm() != 0 ||
+ // FalseInstr->getOperand(2).getReg() != TrueReg)
+ // return false;
+
+ return true;
+}
+void applySPIRVFaceForward(MachineInstr &MI, MachineRegisterInfo &MRI,
+ MachineIRBuilder &B) {
+
+ // Extract the operands for N, I, and Ng from the match criteria.
+ Register CondReg = MI.getOperand(1).getReg();
+ MachineInstr *CondInstr = MRI.getVRegDef(CondReg);
+ Register DotReg = CondInstr->getOperand(1).getReg();
+ MachineInstr *DotInstr = MRI.getVRegDef(DotReg);
+ Register DotOperand1 = DotInstr->getOperand(2).getReg(); // I
+ Register DotOperand2 = DotInstr->getOperand(3).getReg(); // Ng
+ Register TrueReg = MI.getOperand(2).getReg(); // N
+ Register FalseReg = MI.getOperand(3).getReg();
+ MachineInstr *FalseInstr = MRI.getVRegDef(FalseReg);
+
+ // Remove the original `select` instruction
+ Register ResultReg = MI.getOperand(0).getReg();
+ DebugLoc DL = MI.getDebugLoc();
+ MachineBasicBlock &MBB = *MI.getParent();
+ MachineBasicBlock::iterator InsertPt = MI.getIterator();
+
+ // Build the `spv_faceforward` intrinsic
+ MachineInstrBuilder NewInstr =
+ BuildMI(MBB, InsertPt, DL, B.getTII().get(TargetOpcode::G_INTRINSIC));
+ NewInstr
+ .addDef(ResultReg) // Result register
+ .addIntrinsicID(Intrinsic::spv_faceforward) // Intrinsic ID
+ .addUse(TrueReg) // Operand N
+ .addUse(DotOperand1) // Operand I
+ .addUse(DotOperand2); // Operand Ng
+
+ SPIRVGlobalRegistry *GR =
+ MI.getMF()->getSubtarget<SPIRVSubtarget>().getSPIRVGlobalRegistry();
+ auto RemoveAllUses = [&](Register Reg) {
+ SmallVector<MachineInstr *, 4> UsesToErase;
+ for (auto &UseMI : MRI.use_instructions(Reg))
+ UsesToErase.push_back(&UseMI);
+
+ // calling eraseFromParent to early invalidates the iterator.
+ for (auto *MIToErase : UsesToErase) {
+ GR->invalidateMachineInstr(MIToErase);
+ MIToErase->eraseFromParent();
+ }
+ };
+ RemoveAllUses(CondReg); // remove all uses of FCMP Result
+ GR->invalidateMachineInstr(CondInstr);
+ CondInstr->eraseFromParent(); // remove FCMP instruction
+ RemoveAllUses(DotReg); // remove all uses of spv_fdot Result
+ GR->invalidateMachineInstr(DotInstr);
+ DotInstr->eraseFromParent(); // remove spv_fdot instruction
+ RemoveAllUses(FalseReg); // remove all uses of FSUB Result
+ GR->invalidateMachineInstr(FalseInstr);
+ FalseInstr->eraseFromParent(); // remove FSUB instruction
+}
+
class SPIRVPreLegalizerCombinerImpl : public Combiner {
protected:
const CombinerHelper Helper;
diff --git a/llvm/test/CodeGen/SPIRV/GlobalISel/InstCombine/prelegalizercombiner-select-to-faceforward.mir b/llvm/test/CodeGen/SPIRV/GlobalISel/InstCombine/prelegalizercombiner-select-to-faceforward.mir
new file mode 100644
index 0000000000000..e7f1fde0becee
--- /dev/null
+++ b/llvm/test/CodeGen/SPIRV/GlobalISel/InstCombine/prelegalizercombiner-select-to-faceforward.mir
@@ -0,0 +1,33 @@
+# RUN: llc -verify-machineinstrs -O0 -mtriple spirv-unknown-unknown -run-pass=spirv-prelegalizer-combiner %s -o - | FileCheck %s
+# REQUIRES: asserts
+---
+name: faceforward_instcombine_float4
+tracksRegLiveness: true
+legalized: true
+body: |
+ bb.1.entry:
+ ; CHECK-LABEL: name: faceforward_instcombine_float4
+ ; CHECK-NOT: %6:_(<4 x s32>) = G_FSUB %2, %3
+ ; CHECK-NOT: %7:id(s32) = G_INTRINSIC intrinsic(@llvm.spv.length), %6(<4 x s32>)
+ ; CHECK: %7:id(s32) = G_INTRINSIC intrinsic(@llvm.spv.distance), %2(<4 x s32>), %3(<4 x s32>)
+ %4:type(s64) = OpTypeVector %3:type(s64), 4
+ %6:type(s64) = OpTypeFunction %4:type(s64), %4:type(s64), %4:type(s64), %4:type(s64)
+ %3:type(s64) = OpTypeFloat 32
+ OpName %0:vfid(<4 x s32>), 97
+ OpName %1:vfid(<4 x s32>), 98
+ OpName %2:vfid(<4 x s32>), 99
+ %5:iid(s64) = OpFunction %4:type(s64), 0, %6:type(s64)
+ %0:vfid(<4 x s32>) = OpFunctionParameter %4:type(s64)
+ %1:vfid(<4 x s32>) = OpFunctionParameter %4:type(s64)
+ %2:vfid(<4 x s32>) = OpFunctionParameter %4:type(s64)
+ OpName %5:iid(s64), 1701011814, 2003988326, 1600418401, 1953721961, 1651339107, 1600482921, 1634692198, 13428
+ OpDecorate %5:iid(s64), 41, 1701011814, 2003988326, 1600418401, 1953721961, 1651339107, 1600482921, 1634692198, 13428, 0
+ %10:_(s32) = G_FCONSTANT float 0.000000e+00
+ %9:_(s32) = G_INTRINSIC intrinsic(@llvm.spv.fdot), %1:vfid(<4 x s32>), %2:vfid(<4 x s32>)
+ %11:_(s1) = G_FCMP floatpred(olt), %9:_(s32), %10:_
+ %12:_(<4 x s32>) = G_INTRINSIC_W_SIDE_EFFECTS intrinsic(@llvm.spv.const.composite)
+ %13:_(<4 x s32>) = G_INTRINSIC_W_SIDE_EFFECTS intrinsic(@llvm.spv.track.constant), %12:_(<4 x s32>), <0x55555d14f908>
+ %14:_(<4 x s32>) = G_FSUB %13:_, %0:vfid
+ %15:id(<4 x s32>) = G_SELECT %11:_(s1), %0:vfid, %14:_
+ OpReturnValue %15:id(<4 x s32>)
+
\ No newline at end of file
diff --git a/llvm/test/CodeGen/SPIRV/hlsl-intrinsics/faceforward.ll b/llvm/test/CodeGen/SPIRV/hlsl-intrinsics/faceforward.ll
index 22742169506f2..c566e863ba428 100644
--- a/llvm/test/CodeGen/SPIRV/hlsl-intrinsics/faceforward.ll
+++ b/llvm/test/CodeGen/SPIRV/hlsl-intrinsics/faceforward.ll
@@ -11,49 +11,19 @@
; CHECK-DAG: %[[#float_32:]] = OpTypeFloat 32
; CHECK-DAG: %[[#vec4_float_32:]] = OpTypeVector %[[#float_32]] 4
-define noundef half @faceforward_half(half noundef %a, half noundef %b, half noundef %c) {
-entry:
- ; CHECK: %[[#]] = OpFunction %[[#float_16]] None %[[#]]
- ; CHECK: %[[#arg0:]] = OpFunctionParameter %[[#float_16]]
- ; CHECK: %[[#arg1:]] = OpFunctionParameter %[[#float_16]]
- ; CHECK: %[[#arg2:]] = OpFunctionParameter %[[#float_16]]
- ; CHECK: %[[#]] = OpExtInst %[[#float_16]] %[[#op_ext_glsl]] FaceForward %[[#arg0]] %[[#arg1]] %[[#arg2]]
- %spv.faceforward = call half @llvm.spv.faceforward.f16(half %a, half %b, half %c)
- ret half %spv.faceforward
-}
-
-define noundef float @faceforward_float(float noundef %a, float noundef %b, float noundef %c) {
-entry:
- ; CHECK: %[[#]] = OpFunction %[[#float_32]] None %[[#]]
- ; CHECK: %[[#arg0:]] = OpFunctionParameter %[[#float_32]]
- ; CHECK: %[[#arg1:]] = OpFunctionParameter %[[#float_32]]
- ; CHECK: %[[#arg2:]] = OpFunctionParameter %[[#float_32]]
- ; CHECK: %[[#]] = OpExtInst %[[#float_32]] %[[#op_ext_glsl]] FaceForward %[[#arg0]] %[[#arg1]] %[[#arg2]]
- %spv.faceforward = call float @llvm.spv.faceforward.f32(float %a, float %b, float %c)
- ret float %spv.faceforward
-}
-
-define noundef <4 x half> @faceforward_half4(<4 x half> noundef %a, <4 x half> noundef %b, <4 x half> noundef %c) {
-entry:
- ; CHECK: %[[#]] = OpFunction %[[#vec4_float_16]] None %[[#]]
- ; CHECK: %[[#arg0:]] = OpFunctionParameter %[[#vec4_float_16]]
- ; CHECK: %[[#arg1:]] = OpFunctionParameter %[[#vec4_float_16]]
- ; CHECK: %[[#arg2:]] = OpFunctionParameter %[[#vec4_float_16]]
- ; CHECK: %[[#]] = OpExtInst %[[#vec4_float_16]] %[[#op_ext_glsl]] FaceForward %[[#arg0]] %[[#arg1]] %[[#arg2]]
- %spv.faceforward = call <4 x half> @llvm.spv.faceforward.v4f16(<4 x half> %a, <4 x half> %b, <4 x half> %c)
- ret <4 x half> %spv.faceforward
-}
-
-define noundef <4 x float> @faceforward_float4(<4 x float> noundef %a, <4 x float> noundef %b, <4 x float> noundef %c) {
+define noundef <4 x float> @faceforward_instcombine_float4(<4 x float> noundef %a, <4 x float> noundef %b, <4 x float> noundef %c) {
entry:
; CHECK: %[[#]] = OpFunction %[[#vec4_float_32]] None %[[#]]
; CHECK: %[[#arg0:]] = OpFunctionParameter %[[#vec4_float_32]]
; CHECK: %[[#arg1:]] = OpFunctionParameter %[[#vec4_float_32]]
; CHECK: %[[#arg2:]] = OpFunctionParameter %[[#vec4_float_32]]
; CHECK: %[[#]] = OpExtInst %[[#vec4_float_32]] %[[#op_ext_glsl]] FaceForward %[[#arg0]] %[[#arg1]] %[[#arg2]]
- %spv.faceforward = call <4 x float> @llvm.spv.faceforward.v4f32(<4 x float> %a, <4 x float> %b, <4 x float> %c)
- ret <4 x float> %spv.faceforward
-}
+ %spv.fdot = call float @llvm.spv.fdot.v4f32(<4 x float> %b, <4 x float> %c)
+ %fcmp = fcmp olt float %spv.fdot, 0.000000e+00
+ %delta = fsub <4 x float> zeroinitializer, %a
+ %select = select i1 %fcmp, <4 x float> %a, <4 x float> %delta
+ ret <4 x float> %select
+ }
declare half @llvm.spv.faceforward.f16(half, half, half)
declare float @llvm.spv.faceforward.f32(float, float, float)
>From a9459be987dae44d25d437a9582227981ac92d73 Mon Sep 17 00:00:00 2001
From: kmpeng <kaitlinpeng at microsoft.com>
Date: Tue, 13 May 2025 16:15:11 -0700
Subject: [PATCH 2/5] finished implementation, modified tests
---
.../lib/Headers/hlsl/hlsl_intrinsic_helpers.h | 5 -
.../CodeGenHLSL/builtins/faceforward.hlsl | 56 +++++++----
.../SPIRV/SPIRVPreLegalizerCombiner.cpp | 95 ++++++++-----------
...egalizercombiner-select-to-faceforward.mir | 17 ++--
.../SPIRV/hlsl-intrinsics/faceforward.ll | 46 ++++++++-
.../CodeGen/SPIRV/opencl/faceforward-error.ll | 13 +++
6 files changed, 146 insertions(+), 86 deletions(-)
create mode 100644 llvm/test/CodeGen/SPIRV/opencl/faceforward-error.ll
diff --git a/clang/lib/Headers/hlsl/hlsl_intrinsic_helpers.h b/clang/lib/Headers/hlsl/hlsl_intrinsic_helpers.h
index 68dc6d96f89c1..e1996fd3e30ed 100644
--- a/clang/lib/Headers/hlsl/hlsl_intrinsic_helpers.h
+++ b/clang/lib/Headers/hlsl/hlsl_intrinsic_helpers.h
@@ -127,11 +127,6 @@ template <typename T> constexpr vector<T, 4> lit_impl(T NDotL, T NDotH, T M) {
}
template <typename T> constexpr T faceforward_impl(T N, T I, T Ng) {
-// #if (__has_builtin(__builtin_spirv_faceforward))
-// return __builtin_spirv_faceforward(N, I, Ng);
-// #else
-// return select(dot(I, Ng) < 0, N, -N);
-// #endif
return select(dot(I, Ng) < 0, N, -N);
}
diff --git a/clang/test/CodeGenHLSL/builtins/faceforward.hlsl b/clang/test/CodeGenHLSL/builtins/faceforward.hlsl
index d2ece57aba4ae..f12f75f384964 100644
--- a/clang/test/CodeGenHLSL/builtins/faceforward.hlsl
+++ b/clang/test/CodeGenHLSL/builtins/faceforward.hlsl
@@ -12,8 +12,11 @@
// CHECK: %hlsl.select.i = select reassoc nnan ninf nsz arcp afn i1 %cmp.i, half %{{.*}}, half %fneg.i
// CHECK: ret half %hlsl.select.i
// SPVCHECK-LABEL: test_faceforward_half
-// SPVCHECK: %spv.faceforward.i = call reassoc nnan ninf nsz arcp afn noundef half @llvm.spv.faceforward.f16(half %{{.*}}, half %{{.*}}, half %{{.*}})
-// SPVCHECK: ret half %spv.faceforward.i
+// SPVCHECK: %hlsl.dot.i = fmul reassoc nnan ninf nsz arcp afn half %{{.*}}, %{{.*}}
+// SPVCHECK: %cmp.i = fcmp reassoc nnan ninf nsz arcp afn olt half %hlsl.dot.i, 0xH0000
+// SPVCHECK: %fneg.i = fneg reassoc nnan ninf nsz arcp afn half %{{.*}}
+// SPVCHECK: %hlsl.select.i = select reassoc nnan ninf nsz arcp afn i1 %cmp.i, half %{{.*}}, half %fneg.i
+// SPVCHECK: ret half %hlsl.select.i
half test_faceforward_half(half N, half I, half Ng) { return faceforward(N, I, Ng); }
// CHECK-LABEL: test_faceforward_half2
@@ -23,8 +26,11 @@ half test_faceforward_half(half N, half I, half Ng) { return faceforward(N, I, N
// CHECK: %hlsl.select.i = select reassoc nnan ninf nsz arcp afn i1 %cmp.i, <2 x half> %{{.*}}, <2 x half> %fneg.i
// CHECK: ret <2 x half> %hlsl.select.i
// SPVCHECK-LABEL: test_faceforward_half2
-// SPVCHECK: %spv.faceforward.i = call reassoc nnan ninf nsz arcp afn noundef <2 x half> @llvm.spv.faceforward.v2f16(<2 x half> %{{.*}}, <2 x half> %{{.*}}, <2 x half> %{{.*}})
-// SPVCHECK: ret <2 x half> %spv.faceforward.i
+// SPVCHECK: %hlsl.dot.i = call reassoc nnan ninf nsz arcp afn half @llvm.spv.fdot.v2f16(<2 x half> %{{.*}}, <2 x half> %{{.*}})
+// SPVCHECK: %cmp.i = fcmp reassoc nnan ninf nsz arcp afn olt half %hlsl.dot.i, 0xH0000
+// SPVCHECK: %fneg.i = fneg reassoc nnan ninf nsz arcp afn <2 x half> %{{.*}}
+// SPVCHECK: %hlsl.select.i = select reassoc nnan ninf nsz arcp afn i1 %cmp.i, <2 x half> %{{.*}}, <2 x half> %fneg.i
+// SPVCHECK: ret <2 x half> %hlsl.select.i
half2 test_faceforward_half2(half2 N, half2 I, half2 Ng) { return faceforward(N, I, Ng); }
// CHECK-LABEL: test_faceforward_half3
@@ -34,8 +40,11 @@ half2 test_faceforward_half2(half2 N, half2 I, half2 Ng) { return faceforward(N,
// CHECK: %hlsl.select.i = select reassoc nnan ninf nsz arcp afn i1 %cmp.i, <3 x half> %{{.*}}, <3 x half> %fneg.i
// CHECK: ret <3 x half> %hlsl.select.i
// SPVCHECK-LABEL: test_faceforward_half3
-// SPVCHECK: %spv.faceforward.i = call reassoc nnan ninf nsz arcp afn noundef <3 x half> @llvm.spv.faceforward.v3f16(<3 x half> %{{.*}}, <3 x half> %{{.*}}, <3 x half> %{{.*}})
-// SPVCHECK: ret <3 x half> %spv.faceforward.i
+// SPVCHECK: %hlsl.dot.i = call reassoc nnan ninf nsz arcp afn half @llvm.spv.fdot.v3f16(<3 x half> %{{.*}}, <3 x half> %{{.*}})
+// SPVCHECK: %cmp.i = fcmp reassoc nnan ninf nsz arcp afn olt half %hlsl.dot.i, 0xH0000
+// SPVCHECK: %fneg.i = fneg reassoc nnan ninf nsz arcp afn <3 x half> %{{.*}}
+// SPVCHECK: %hlsl.select.i = select reassoc nnan ninf nsz arcp afn i1 %cmp.i, <3 x half> %{{.*}}, <3 x half> %fneg.i
+// SPVCHECK: ret <3 x half> %hlsl.select.i
half3 test_faceforward_half3(half3 N, half3 I, half3 Ng) { return faceforward(N, I, Ng); }
// CHECK-LABEL: test_faceforward_half4
@@ -45,8 +54,11 @@ half3 test_faceforward_half3(half3 N, half3 I, half3 Ng) { return faceforward(N,
// CHECK: %hlsl.select.i = select reassoc nnan ninf nsz arcp afn i1 %cmp.i, <4 x half> %{{.*}}, <4 x half> %fneg.i
// CHECK: ret <4 x half> %hlsl.select.i
// SPVCHECK-LABEL: test_faceforward_half4
-// SPVCHECK: %spv.faceforward.i = call reassoc nnan ninf nsz arcp afn noundef <4 x half> @llvm.spv.faceforward.v4f16(<4 x half> %{{.*}}, <4 x half> %{{.*}}, <4 x half> %{{.*}})
-// SPVCHECK: ret <4 x half> %spv.faceforward.i
+// SPVCHECK: %hlsl.dot.i = call reassoc nnan ninf nsz arcp afn half @llvm.spv.fdot.v4f16(<4 x half> %{{.*}}, <4 x half> %{{.*}})
+// SPVCHECK: %cmp.i = fcmp reassoc nnan ninf nsz arcp afn olt half %hlsl.dot.i, 0xH0000
+// SPVCHECK: %fneg.i = fneg reassoc nnan ninf nsz arcp afn <4 x half> %{{.*}}
+// SPVCHECK: %hlsl.select.i = select reassoc nnan ninf nsz arcp afn i1 %cmp.i, <4 x half> %{{.*}}, <4 x half> %fneg.i
+// SPVCHECK: ret <4 x half> %hlsl.select.i
half4 test_faceforward_half4(half4 N, half4 I, half4 Ng) { return faceforward(N, I, Ng); }
// CHECK-LABEL: test_faceforward_float
@@ -56,8 +68,11 @@ half4 test_faceforward_half4(half4 N, half4 I, half4 Ng) { return faceforward(N,
// CHECK: %hlsl.select.i = select reassoc nnan ninf nsz arcp afn i1 %cmp.i, float %{{.*}}, float %fneg.i
// CHECK: ret float %hlsl.select.i
// SPVCHECK-LABEL: test_faceforward_float
-// SPVCHECK: %spv.faceforward.i = call reassoc nnan ninf nsz arcp afn noundef float @llvm.spv.faceforward.f32(float %{{.*}}, float %{{.*}}, float %{{.*}})
-// SPVCHECK: ret float %spv.faceforward.i
+// SPVCHECK: %hlsl.dot.i = fmul reassoc nnan ninf nsz arcp afn float %{{.*}}, %{{.*}}
+// SPVCHECK: %cmp.i = fcmp reassoc nnan ninf nsz arcp afn olt float %hlsl.dot.i, 0.000000e+00
+// SPVCHECK: %fneg.i = fneg reassoc nnan ninf nsz arcp afn float %{{.*}}
+// SPVCHECK: %hlsl.select.i = select reassoc nnan ninf nsz arcp afn i1 %cmp.i, float %{{.*}}, float %fneg.i
+// SPVCHECK: ret float %hlsl.select.i
float test_faceforward_float(float N, float I, float Ng) { return faceforward(N, I, Ng); }
// CHECK-LABEL: test_faceforward_float2
@@ -67,8 +82,11 @@ float test_faceforward_float(float N, float I, float Ng) { return faceforward(N,
// CHECK: %hlsl.select.i = select reassoc nnan ninf nsz arcp afn i1 %cmp.i, <2 x float> %{{.*}}, <2 x float> %fneg.i
// CHECK: ret <2 x float> %hlsl.select.i
// SPVCHECK-LABEL: test_faceforward_float2
-// SPVCHECK: %spv.faceforward.i = call reassoc nnan ninf nsz arcp afn noundef <2 x float> @llvm.spv.faceforward.v2f32(<2 x float> %{{.*}}, <2 x float> %{{.*}}, <2 x float> %{{.*}})
-// SPVCHECK: ret <2 x float> %spv.faceforward.i
+// SPVCHECK: %hlsl.dot.i = call reassoc nnan ninf nsz arcp afn float @llvm.spv.fdot.v2f32(<2 x float> %{{.*}}, <2 x float> %{{.*}})
+// SPVCHECK: %cmp.i = fcmp reassoc nnan ninf nsz arcp afn olt float %hlsl.dot.i, 0.000000e+00
+// SPVCHECK: %fneg.i = fneg reassoc nnan ninf nsz arcp afn <2 x float> %{{.*}}
+// SPVCHECK: %hlsl.select.i = select reassoc nnan ninf nsz arcp afn i1 %cmp.i, <2 x float> %{{.*}}, <2 x float> %fneg.i
+// SPVCHECK: ret <2 x float> %hlsl.select.i
float2 test_faceforward_float2(float2 N, float2 I, float2 Ng) { return faceforward(N, I, Ng); }
// CHECK-LABEL: test_faceforward_float3
@@ -78,8 +96,11 @@ float2 test_faceforward_float2(float2 N, float2 I, float2 Ng) { return faceforwa
// CHECK: %hlsl.select.i = select reassoc nnan ninf nsz arcp afn i1 %cmp.i, <3 x float> %{{.*}}, <3 x float> %fneg.i
// CHECK: ret <3 x float> %hlsl.select.i
// SPVCHECK-LABEL: test_faceforward_float3
-// SPVCHECK: %spv.faceforward.i = call reassoc nnan ninf nsz arcp afn noundef <3 x float> @llvm.spv.faceforward.v3f32(<3 x float> %{{.*}}, <3 x float> %{{.*}}, <3 x float> %{{.*}})
-// SPVCHECK: ret <3 x float> %spv.faceforward.i
+// SPVCHECK: %hlsl.dot.i = call reassoc nnan ninf nsz arcp afn float @llvm.spv.fdot.v3f32(<3 x float> %{{.*}}, <3 x float> %{{.*}})
+// SPVCHECK: %cmp.i = fcmp reassoc nnan ninf nsz arcp afn olt float %hlsl.dot.i, 0.000000e+00
+// SPVCHECK: %fneg.i = fneg reassoc nnan ninf nsz arcp afn <3 x float> %{{.*}}
+// SPVCHECK: %hlsl.select.i = select reassoc nnan ninf nsz arcp afn i1 %cmp.i, <3 x float> %{{.*}}, <3 x float> %fneg.i
+// SPVCHECK: ret <3 x float> %hlsl.select.i
float3 test_faceforward_float3(float3 N, float3 I, float3 Ng) { return faceforward(N, I, Ng); }
// CHECK-LABEL: test_faceforward_float4
@@ -89,6 +110,9 @@ float3 test_faceforward_float3(float3 N, float3 I, float3 Ng) { return faceforwa
// CHECK: %hlsl.select.i = select reassoc nnan ninf nsz arcp afn i1 %cmp.i, <4 x float> %{{.*}}, <4 x float> %fneg.i
// CHECK: ret <4 x float> %hlsl.select.i
// SPVCHECK-LABEL: test_faceforward_float4
-// SPVCHECK: %spv.faceforward.i = call reassoc nnan ninf nsz arcp afn noundef <4 x float> @llvm.spv.faceforward.v4f32(<4 x float> %{{.*}}, <4 x float> %{{.*}}, <4 x float> %{{.*}})
-// SPVCHECK: ret <4 x float> %spv.faceforward.i
+// SPVCHECK: %hlsl.dot.i = call reassoc nnan ninf nsz arcp afn float @llvm.spv.fdot.v4f32(<4 x float> %{{.*}}, <4 x float> %{{.*}})
+// SPVCHECK: %cmp.i = fcmp reassoc nnan ninf nsz arcp afn olt float %hlsl.dot.i, 0.000000e+00
+// SPVCHECK: %fneg.i = fneg reassoc nnan ninf nsz arcp afn <4 x float> %{{.*}}
+// SPVCHECK: %hlsl.select.i = select reassoc nnan ninf nsz arcp afn i1 %cmp.i, <4 x float> %{{.*}}, <4 x float> %fneg.i
+// SPVCHECK: ret <4 x float> %hlsl.select.i
float4 test_faceforward_float4(float4 N, float4 I, float4 Ng) { return faceforward(N, I, Ng); }
diff --git a/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp b/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp
index d323453e68828..3826707fcbe9d 100644
--- a/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp
+++ b/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp
@@ -50,6 +50,18 @@ namespace {
#include "SPIRVGenPreLegalizeGICombiner.inc"
#undef GET_GICOMBINER_TYPES
+static void removeAllUses(Register Reg, MachineRegisterInfo &MRI,
+ SPIRVGlobalRegistry *GR) {
+ SmallVector<MachineInstr *, 4> UsesToErase(
+ llvm::make_pointer_range(MRI.use_instructions(Reg)));
+
+ // calling eraseFromParent too early invalidates the iterator.
+ for (auto *MIToErase : UsesToErase) {
+ GR->invalidateMachineInstr(MIToErase);
+ MIToErase->eraseFromParent();
+ }
+}
+
/// This match is part of a combine that
/// rewrites length(X - Y) to distance(X, Y)
/// (f32 (g_intrinsic length
@@ -98,17 +110,7 @@ void applySPIRVDistance(MachineInstr &MI, MachineRegisterInfo &MRI,
SPIRVGlobalRegistry *GR =
MI.getMF()->getSubtarget<SPIRVSubtarget>().getSPIRVGlobalRegistry();
- auto RemoveAllUses = [&](Register Reg) {
- SmallVector<MachineInstr *, 4> UsesToErase(
- llvm::make_pointer_range(MRI.use_instructions(Reg)));
-
- // calling eraseFromParent to early invalidates the iterator.
- for (auto *MIToErase : UsesToErase) {
- GR->invalidateMachineInstr(MIToErase);
- MIToErase->eraseFromParent();
- }
- };
- RemoveAllUses(SubDestReg); // remove all uses of FSUB Result
+ removeAllUses(SubDestReg, MRI, GR); // remove all uses of FSUB Result
GR->invalidateMachineInstr(SubInstr);
SubInstr->eraseFromParent(); // remove FSUB instruction
}
@@ -128,50 +130,48 @@ void applySPIRVDistance(MachineInstr &MI, MachineRegisterInfo &MRI,
bool matchSelectToFaceForward(MachineInstr &MI, MachineRegisterInfo &MRI) {
if (MI.getOpcode() != TargetOpcode::G_SELECT)
return false;
-
+
// Check if the condition is a comparison between a dot product and zero
Register CondReg = MI.getOperand(1).getReg();
MachineInstr *CondInstr = MRI.getVRegDef(CondReg);
if (!CondInstr || CondInstr->getOpcode() != TargetOpcode::G_FCMP)
return false;
- if (!CondInstr->getOperand(2).getReg())
- return false;
Register DotReg = CondInstr->getOperand(2).getReg();
MachineInstr *DotInstr = MRI.getVRegDef(DotReg);
// fmul?
- if (DotInstr->getOpcode() != TargetOpcode::G_INTRINSIC || cast<GIntrinsic>(DotInstr)->getIntrinsicID() != Intrinsic::spv_fdot)
+ if (DotInstr->getOpcode() != TargetOpcode::G_INTRINSIC ||
+ cast<GIntrinsic>(DotInstr)->getIntrinsicID() != Intrinsic::spv_fdot)
+ return false;
+
+ Register CondZeroReg = CondInstr->getOperand(3).getReg();
+ MachineInstr *CondZeroInstr = MRI.getVRegDef(CondZeroReg);
+ if (CondZeroInstr->getOpcode() != TargetOpcode::G_FCONSTANT ||
+ !CondZeroInstr->getOperand(1).getFPImm()->isZero())
+ return false;
+
+ // Check if the false operand is the negation of the true operand
+ Register TrueReg = MI.getOperand(2).getReg();
+ Register FalseReg = MI.getOperand(3).getReg();
+ MachineInstr *FalseInstr = MRI.getVRegDef(FalseReg);
+ if (FalseInstr->getOpcode() != TargetOpcode::G_FNEG)
+ return false;
+ if (TrueReg != FalseInstr->getOperand(1).getReg())
return false;
- // // is using getImm() correct?
- // if (!CondInstr->getOperand(3).isImm() ||
- // CondInstr->getOperand(3).getImm() != 0)
- // return false;
-
- // // Check if the false operand is the negation of the true operand
- // Register TrueReg = MI.getOperand(2).getReg();
- // Register FalseReg = MI.getOperand(3).getReg();
- // MachineInstr *FalseInstr = MRI.getVRegDef(FalseReg);
- // // getImm() correct?
- // if (FalseInstr->getOpcode() != TargetOpcode::G_FSUB ||
- // FalseInstr->getOperand(1).getImm() != 0 ||
- // FalseInstr->getOperand(2).getReg() != TrueReg)
- // return false;
return true;
}
void applySPIRVFaceForward(MachineInstr &MI, MachineRegisterInfo &MRI,
- MachineIRBuilder &B) {
+ MachineIRBuilder &B) {
// Extract the operands for N, I, and Ng from the match criteria.
Register CondReg = MI.getOperand(1).getReg();
MachineInstr *CondInstr = MRI.getVRegDef(CondReg);
- Register DotReg = CondInstr->getOperand(1).getReg();
+ Register DotReg = CondInstr->getOperand(2).getReg();
MachineInstr *DotInstr = MRI.getVRegDef(DotReg);
Register DotOperand1 = DotInstr->getOperand(2).getReg(); // I
Register DotOperand2 = DotInstr->getOperand(3).getReg(); // Ng
- Register TrueReg = MI.getOperand(2).getReg(); // N
- Register FalseReg = MI.getOperand(3).getReg();
- MachineInstr *FalseInstr = MRI.getVRegDef(FalseReg);
+ Register TrueReg = MI.getOperand(2).getReg(); // N
// Remove the original `select` instruction
Register ResultReg = MI.getOperand(0).getReg();
@@ -183,34 +183,17 @@ void applySPIRVFaceForward(MachineInstr &MI, MachineRegisterInfo &MRI,
MachineInstrBuilder NewInstr =
BuildMI(MBB, InsertPt, DL, B.getTII().get(TargetOpcode::G_INTRINSIC));
NewInstr
- .addDef(ResultReg) // Result register
+ .addDef(ResultReg) // Result register
.addIntrinsicID(Intrinsic::spv_faceforward) // Intrinsic ID
- .addUse(TrueReg) // Operand N
- .addUse(DotOperand1) // Operand I
- .addUse(DotOperand2); // Operand Ng
+ .addUse(TrueReg) // Operand N
+ .addUse(DotOperand1) // Operand I
+ .addUse(DotOperand2); // Operand Ng
SPIRVGlobalRegistry *GR =
MI.getMF()->getSubtarget<SPIRVSubtarget>().getSPIRVGlobalRegistry();
- auto RemoveAllUses = [&](Register Reg) {
- SmallVector<MachineInstr *, 4> UsesToErase;
- for (auto &UseMI : MRI.use_instructions(Reg))
- UsesToErase.push_back(&UseMI);
-
- // calling eraseFromParent to early invalidates the iterator.
- for (auto *MIToErase : UsesToErase) {
- GR->invalidateMachineInstr(MIToErase);
- MIToErase->eraseFromParent();
- }
- };
- RemoveAllUses(CondReg); // remove all uses of FCMP Result
+ removeAllUses(CondReg, MRI, GR); // remove all uses of FCMP Result
GR->invalidateMachineInstr(CondInstr);
CondInstr->eraseFromParent(); // remove FCMP instruction
- RemoveAllUses(DotReg); // remove all uses of spv_fdot Result
- GR->invalidateMachineInstr(DotInstr);
- DotInstr->eraseFromParent(); // remove spv_fdot instruction
- RemoveAllUses(FalseReg); // remove all uses of FSUB Result
- GR->invalidateMachineInstr(FalseInstr);
- FalseInstr->eraseFromParent(); // remove FSUB instruction
}
class SPIRVPreLegalizerCombinerImpl : public Combiner {
diff --git a/llvm/test/CodeGen/SPIRV/GlobalISel/InstCombine/prelegalizercombiner-select-to-faceforward.mir b/llvm/test/CodeGen/SPIRV/GlobalISel/InstCombine/prelegalizercombiner-select-to-faceforward.mir
index e7f1fde0becee..4fbc3d0735b68 100644
--- a/llvm/test/CodeGen/SPIRV/GlobalISel/InstCombine/prelegalizercombiner-select-to-faceforward.mir
+++ b/llvm/test/CodeGen/SPIRV/GlobalISel/InstCombine/prelegalizercombiner-select-to-faceforward.mir
@@ -7,9 +7,12 @@ legalized: true
body: |
bb.1.entry:
; CHECK-LABEL: name: faceforward_instcombine_float4
- ; CHECK-NOT: %6:_(<4 x s32>) = G_FSUB %2, %3
- ; CHECK-NOT: %7:id(s32) = G_INTRINSIC intrinsic(@llvm.spv.length), %6(<4 x s32>)
- ; CHECK: %7:id(s32) = G_INTRINSIC intrinsic(@llvm.spv.distance), %2(<4 x s32>), %3(<4 x s32>)
+ ; CHECK-NOT: %10:_(s32) = G_FCONSTANT float 0.000000e+00
+ ; CHECK-NOT: %9:_(s32) = G_INTRINSIC intrinsic(@llvm.spv.fdot), %1:vfid(<4 x s32>), %2:vfid(<4 x s32>)
+ ; CHECK-NOT: %11:_(s1) = G_FCMP floatpred(olt), %9:_(s32), %10:_
+ ; CHECK-NOT: %12:_(<4 x s32>) = G_FNEG %0:vfid
+ ; CHECK-NOT: %13:id(<4 x s32>) = G_SELECT %11:_(s1), %0:vfid, %12:_
+ ; CHECK: %11:id(<4 x s32>) = G_INTRINSIC intrinsic(@llvm.spv.faceforward), %3(<4 x s32>), %4(<4 x s32>), %5(<4 x s32>)
%4:type(s64) = OpTypeVector %3:type(s64), 4
%6:type(s64) = OpTypeFunction %4:type(s64), %4:type(s64), %4:type(s64), %4:type(s64)
%3:type(s64) = OpTypeFloat 32
@@ -25,9 +28,7 @@ body: |
%10:_(s32) = G_FCONSTANT float 0.000000e+00
%9:_(s32) = G_INTRINSIC intrinsic(@llvm.spv.fdot), %1:vfid(<4 x s32>), %2:vfid(<4 x s32>)
%11:_(s1) = G_FCMP floatpred(olt), %9:_(s32), %10:_
- %12:_(<4 x s32>) = G_INTRINSIC_W_SIDE_EFFECTS intrinsic(@llvm.spv.const.composite)
- %13:_(<4 x s32>) = G_INTRINSIC_W_SIDE_EFFECTS intrinsic(@llvm.spv.track.constant), %12:_(<4 x s32>), <0x55555d14f908>
- %14:_(<4 x s32>) = G_FSUB %13:_, %0:vfid
- %15:id(<4 x s32>) = G_SELECT %11:_(s1), %0:vfid, %14:_
- OpReturnValue %15:id(<4 x s32>)
+ %12:_(<4 x s32>) = G_FNEG %0:vfid
+ %13:id(<4 x s32>) = G_SELECT %11:_(s1), %0:vfid, %12:_
+ OpReturnValue %13:id(<4 x s32>)
\ No newline at end of file
diff --git a/llvm/test/CodeGen/SPIRV/hlsl-intrinsics/faceforward.ll b/llvm/test/CodeGen/SPIRV/hlsl-intrinsics/faceforward.ll
index c566e863ba428..b3dccc929ae71 100644
--- a/llvm/test/CodeGen/SPIRV/hlsl-intrinsics/faceforward.ll
+++ b/llvm/test/CodeGen/SPIRV/hlsl-intrinsics/faceforward.ll
@@ -11,6 +11,50 @@
; CHECK-DAG: %[[#float_32:]] = OpTypeFloat 32
; CHECK-DAG: %[[#vec4_float_32:]] = OpTypeVector %[[#float_32]] 4
+define noundef half @faceforward_half(half noundef %a, half noundef %b, half noundef %c) {
+entry:
+ ; CHECK: %[[#]] = OpFunction %[[#float_16]] None %[[#]]
+ ; CHECK: %[[#arg0:]] = OpFunctionParameter %[[#float_16]]
+ ; CHECK: %[[#arg1:]] = OpFunctionParameter %[[#float_16]]
+ ; CHECK: %[[#arg2:]] = OpFunctionParameter %[[#float_16]]
+ ; CHECK: %[[#]] = OpExtInst %[[#float_16]] %[[#op_ext_glsl]] FaceForward %[[#arg0]] %[[#arg1]] %[[#arg2]]
+ %spv.faceforward = call half @llvm.spv.faceforward.f16(half %a, half %b, half %c)
+ ret half %spv.faceforward
+}
+
+define noundef float @faceforward_float(float noundef %a, float noundef %b, float noundef %c) {
+entry:
+ ; CHECK: %[[#]] = OpFunction %[[#float_32]] None %[[#]]
+ ; CHECK: %[[#arg0:]] = OpFunctionParameter %[[#float_32]]
+ ; CHECK: %[[#arg1:]] = OpFunctionParameter %[[#float_32]]
+ ; CHECK: %[[#arg2:]] = OpFunctionParameter %[[#float_32]]
+ ; CHECK: %[[#]] = OpExtInst %[[#float_32]] %[[#op_ext_glsl]] FaceForward %[[#arg0]] %[[#arg1]] %[[#arg2]]
+ %spv.faceforward = call float @llvm.spv.faceforward.f32(float %a, float %b, float %c)
+ ret float %spv.faceforward
+}
+
+define noundef <4 x half> @faceforward_half4(<4 x half> noundef %a, <4 x half> noundef %b, <4 x half> noundef %c) {
+entry:
+ ; CHECK: %[[#]] = OpFunction %[[#vec4_float_16]] None %[[#]]
+ ; CHECK: %[[#arg0:]] = OpFunctionParameter %[[#vec4_float_16]]
+ ; CHECK: %[[#arg1:]] = OpFunctionParameter %[[#vec4_float_16]]
+ ; CHECK: %[[#arg2:]] = OpFunctionParameter %[[#vec4_float_16]]
+ ; CHECK: %[[#]] = OpExtInst %[[#vec4_float_16]] %[[#op_ext_glsl]] FaceForward %[[#arg0]] %[[#arg1]] %[[#arg2]]
+ %spv.faceforward = call <4 x half> @llvm.spv.faceforward.v4f16(<4 x half> %a, <4 x half> %b, <4 x half> %c)
+ ret <4 x half> %spv.faceforward
+}
+
+define noundef <4 x float> @faceforward_float4(<4 x float> noundef %a, <4 x float> noundef %b, <4 x float> noundef %c) {
+entry:
+ ; CHECK: %[[#]] = OpFunction %[[#vec4_float_32]] None %[[#]]
+ ; CHECK: %[[#arg0:]] = OpFunctionParameter %[[#vec4_float_32]]
+ ; CHECK: %[[#arg1:]] = OpFunctionParameter %[[#vec4_float_32]]
+ ; CHECK: %[[#arg2:]] = OpFunctionParameter %[[#vec4_float_32]]
+ ; CHECK: %[[#]] = OpExtInst %[[#vec4_float_32]] %[[#op_ext_glsl]] FaceForward %[[#arg0]] %[[#arg1]] %[[#arg2]]
+ %spv.faceforward = call <4 x float> @llvm.spv.faceforward.v4f32(<4 x float> %a, <4 x float> %b, <4 x float> %c)
+ ret <4 x float> %spv.faceforward
+}
+
define noundef <4 x float> @faceforward_instcombine_float4(<4 x float> noundef %a, <4 x float> noundef %b, <4 x float> noundef %c) {
entry:
; CHECK: %[[#]] = OpFunction %[[#vec4_float_32]] None %[[#]]
@@ -20,7 +64,7 @@ entry:
; CHECK: %[[#]] = OpExtInst %[[#vec4_float_32]] %[[#op_ext_glsl]] FaceForward %[[#arg0]] %[[#arg1]] %[[#arg2]]
%spv.fdot = call float @llvm.spv.fdot.v4f32(<4 x float> %b, <4 x float> %c)
%fcmp = fcmp olt float %spv.fdot, 0.000000e+00
- %delta = fsub <4 x float> zeroinitializer, %a
+ %delta = fneg <4 x float> %a
%select = select i1 %fcmp, <4 x float> %a, <4 x float> %delta
ret <4 x float> %select
}
diff --git a/llvm/test/CodeGen/SPIRV/opencl/faceforward-error.ll b/llvm/test/CodeGen/SPIRV/opencl/faceforward-error.ll
new file mode 100644
index 0000000000000..9334e0977347a
--- /dev/null
+++ b/llvm/test/CodeGen/SPIRV/opencl/faceforward-error.ll
@@ -0,0 +1,13 @@
+; RUN: not llc -verify-machineinstrs -O0 -mtriple=spirv64-unknown-unknown %s -o /dev/null 2>&1 | FileCheck %s
+; RUN: not llc -verify-machineinstrs -O0 -mtriple=spirv32-unknown-unknown %s -o /dev/null 2>&1 | FileCheck %s
+
+; CHECK: LLVM ERROR: %{{.*}} = G_INTRINSIC intrinsic(@llvm.spv.faceforward), %{{.*}}, %{{.*}}, %{{.*}} is only supported with the GLSL extended instruction set.
+
+define noundef <4 x float> @faceforward_float4(<4 x float> noundef %a, <4 x float> noundef %b, <4 x float> noundef %c) {
+entry:
+ %spv.faceforward = call <4 x float> @llvm.spv.faceforward.v4f32(<4 x float> %a, <4 x float> %b, <4 x float> %c)
+ ret <4 x float> %spv.faceforward
+}
+
+declare <4 x float> @llvm.spv.faceforward.v4f32(<4 x float>, <4 x float>, <4 x float>)
+
>From 28c391027a16bdd669ddfc924008f656f3296689 Mon Sep 17 00:00:00 2001
From: kmpeng <kaitlinpeng at microsoft.com>
Date: Tue, 13 May 2025 17:18:53 -0700
Subject: [PATCH 3/5] fixed FIXME in faceforward.ll, edited comments
---
.../SPIRV/SPIRVPreLegalizerCombiner.cpp | 15 +++++-----
.../SPIRV/hlsl-intrinsics/faceforward.ll | 28 +++++++++++--------
2 files changed, 24 insertions(+), 19 deletions(-)
diff --git a/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp b/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp
index 3826707fcbe9d..2e1678bf2ea62 100644
--- a/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp
+++ b/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp
@@ -131,7 +131,7 @@ bool matchSelectToFaceForward(MachineInstr &MI, MachineRegisterInfo &MRI) {
if (MI.getOpcode() != TargetOpcode::G_SELECT)
return false;
- // Check if the condition is a comparison between a dot product and zero
+ // Check if select's condition is a comparison between a dot product and 0.
Register CondReg = MI.getOperand(1).getReg();
MachineInstr *CondInstr = MRI.getVRegDef(CondReg);
if (!CondInstr || CondInstr->getOpcode() != TargetOpcode::G_FCMP)
@@ -139,7 +139,6 @@ bool matchSelectToFaceForward(MachineInstr &MI, MachineRegisterInfo &MRI) {
Register DotReg = CondInstr->getOperand(2).getReg();
MachineInstr *DotInstr = MRI.getVRegDef(DotReg);
- // fmul?
if (DotInstr->getOpcode() != TargetOpcode::G_INTRINSIC ||
cast<GIntrinsic>(DotInstr)->getIntrinsicID() != Intrinsic::spv_fdot)
return false;
@@ -150,7 +149,7 @@ bool matchSelectToFaceForward(MachineInstr &MI, MachineRegisterInfo &MRI) {
!CondZeroInstr->getOperand(1).getFPImm()->isZero())
return false;
- // Check if the false operand is the negation of the true operand
+ // Check if select's false operand is the negation of the true operand.
Register TrueReg = MI.getOperand(2).getReg();
Register FalseReg = MI.getOperand(3).getReg();
MachineInstr *FalseInstr = MRI.getVRegDef(FalseReg);
@@ -169,17 +168,17 @@ void applySPIRVFaceForward(MachineInstr &MI, MachineRegisterInfo &MRI,
MachineInstr *CondInstr = MRI.getVRegDef(CondReg);
Register DotReg = CondInstr->getOperand(2).getReg();
MachineInstr *DotInstr = MRI.getVRegDef(DotReg);
- Register DotOperand1 = DotInstr->getOperand(2).getReg(); // I
- Register DotOperand2 = DotInstr->getOperand(3).getReg(); // Ng
- Register TrueReg = MI.getOperand(2).getReg(); // N
+ Register DotOperand1 = DotInstr->getOperand(2).getReg();
+ Register DotOperand2 = DotInstr->getOperand(3).getReg();
+ Register TrueReg = MI.getOperand(2).getReg();
- // Remove the original `select` instruction
+ // Remove the original `select` instruction.
Register ResultReg = MI.getOperand(0).getReg();
DebugLoc DL = MI.getDebugLoc();
MachineBasicBlock &MBB = *MI.getParent();
MachineBasicBlock::iterator InsertPt = MI.getIterator();
- // Build the `spv_faceforward` intrinsic
+ // Build the `spv_faceforward` intrinsic.
MachineInstrBuilder NewInstr =
BuildMI(MBB, InsertPt, DL, B.getTII().get(TargetOpcode::G_INTRINSIC));
NewInstr
diff --git a/llvm/test/CodeGen/SPIRV/hlsl-intrinsics/faceforward.ll b/llvm/test/CodeGen/SPIRV/hlsl-intrinsics/faceforward.ll
index b3dccc929ae71..f181be8ee1200 100644
--- a/llvm/test/CodeGen/SPIRV/hlsl-intrinsics/faceforward.ll
+++ b/llvm/test/CodeGen/SPIRV/hlsl-intrinsics/faceforward.ll
@@ -1,7 +1,5 @@
-; RUN: llc -O0 -verify-machineinstrs -mtriple=spirv-unknown-unknown %s -o - | FileCheck %s
-; RUN: %if spirv-tools %{ llc -O0 -mtriple=spirv-unknown-unknown %s -o - -filetype=obj | spirv-val --target-env spv1.4 %}
-
-; FIXME(#136344): Change --target-env to vulkan1.3 and update this test accordingly once the issue is resolved.
+; RUN: llc -O0 -verify-machineinstrs -mtriple=spirv-vulkan1.3-unknown %s -o - | FileCheck %s
+; RUN: %if spirv-tools %{ llc -O0 -mtriple=spirv-vulkan1.3-unknown %s -o - -filetype=obj | spirv-val --target-env vulkan1.3 %}
; Make sure SPIRV operation function calls for faceforward are lowered correctly.
@@ -11,7 +9,7 @@
; CHECK-DAG: %[[#float_32:]] = OpTypeFloat 32
; CHECK-DAG: %[[#vec4_float_32:]] = OpTypeVector %[[#float_32]] 4
-define noundef half @faceforward_half(half noundef %a, half noundef %b, half noundef %c) {
+define internal noundef half @faceforward_half(half noundef %a, half noundef %b, half noundef %c) {
entry:
; CHECK: %[[#]] = OpFunction %[[#float_16]] None %[[#]]
; CHECK: %[[#arg0:]] = OpFunctionParameter %[[#float_16]]
@@ -22,7 +20,7 @@ entry:
ret half %spv.faceforward
}
-define noundef float @faceforward_float(float noundef %a, float noundef %b, float noundef %c) {
+define internal noundef float @faceforward_float(float noundef %a, float noundef %b, float noundef %c) {
entry:
; CHECK: %[[#]] = OpFunction %[[#float_32]] None %[[#]]
; CHECK: %[[#arg0:]] = OpFunctionParameter %[[#float_32]]
@@ -33,7 +31,7 @@ entry:
ret float %spv.faceforward
}
-define noundef <4 x half> @faceforward_half4(<4 x half> noundef %a, <4 x half> noundef %b, <4 x half> noundef %c) {
+define internal noundef <4 x half> @faceforward_half4(<4 x half> noundef %a, <4 x half> noundef %b, <4 x half> noundef %c) {
entry:
; CHECK: %[[#]] = OpFunction %[[#vec4_float_16]] None %[[#]]
; CHECK: %[[#arg0:]] = OpFunctionParameter %[[#vec4_float_16]]
@@ -44,7 +42,7 @@ entry:
ret <4 x half> %spv.faceforward
}
-define noundef <4 x float> @faceforward_float4(<4 x float> noundef %a, <4 x float> noundef %b, <4 x float> noundef %c) {
+define internal noundef <4 x float> @faceforward_float4(<4 x float> noundef %a, <4 x float> noundef %b, <4 x float> noundef %c) {
entry:
; CHECK: %[[#]] = OpFunction %[[#vec4_float_32]] None %[[#]]
; CHECK: %[[#arg0:]] = OpFunctionParameter %[[#vec4_float_32]]
@@ -55,7 +53,7 @@ entry:
ret <4 x float> %spv.faceforward
}
-define noundef <4 x float> @faceforward_instcombine_float4(<4 x float> noundef %a, <4 x float> noundef %b, <4 x float> noundef %c) {
+define internal noundef <4 x float> @faceforward_instcombine_float4(<4 x float> noundef %a, <4 x float> noundef %b, <4 x float> noundef %c) {
entry:
; CHECK: %[[#]] = OpFunction %[[#vec4_float_32]] None %[[#]]
; CHECK: %[[#arg0:]] = OpFunctionParameter %[[#vec4_float_32]]
@@ -64,13 +62,21 @@ entry:
; CHECK: %[[#]] = OpExtInst %[[#vec4_float_32]] %[[#op_ext_glsl]] FaceForward %[[#arg0]] %[[#arg1]] %[[#arg2]]
%spv.fdot = call float @llvm.spv.fdot.v4f32(<4 x float> %b, <4 x float> %c)
%fcmp = fcmp olt float %spv.fdot, 0.000000e+00
- %delta = fneg <4 x float> %a
- %select = select i1 %fcmp, <4 x float> %a, <4 x float> %delta
+ %fneg = fneg <4 x float> %a
+ %select = select i1 %fcmp, <4 x float> %a, <4 x float> %fneg
ret <4 x float> %select
}
+; The other fucntions are the test, but a entry point is required to have a valid SPIR-V module.
+define void @main() #1 {
+entry:
+ ret void
+}
+
declare half @llvm.spv.faceforward.f16(half, half, half)
declare float @llvm.spv.faceforward.f32(float, float, float)
declare <4 x half> @llvm.spv.faceforward.v4f16(<4 x half>, <4 x half>, <4 x half>)
declare <4 x float> @llvm.spv.faceforward.v4f32(<4 x float>, <4 x float>, <4 x float>)
+
+attributes #1 = { convergent noinline norecurse "hlsl.numthreads"="1,1,1" "hlsl.shader"="compute" "no-trapping-math"="true" "stack-protector-buffer-size"="8" }
>From e6dfc5bd2aa7837e5eee46ea0328124b91b2e103 Mon Sep 17 00:00:00 2001
From: kmpeng <kaitlinpeng at microsoft.com>
Date: Wed, 14 May 2025 13:04:29 -0700
Subject: [PATCH 4/5] added scalar implementation and tests
---
.../SPIRV/SPIRVPreLegalizerCombiner.cpp | 15 +++++++---
...egalizercombiner-select-to-faceforward.mir | 29 +++++++++++++++++++
.../SPIRV/hlsl-intrinsics/faceforward.ll | 14 +++++++++
3 files changed, 54 insertions(+), 4 deletions(-)
diff --git a/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp b/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp
index 2e1678bf2ea62..82c5cbf75b849 100644
--- a/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp
+++ b/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp
@@ -139,8 +139,9 @@ bool matchSelectToFaceForward(MachineInstr &MI, MachineRegisterInfo &MRI) {
Register DotReg = CondInstr->getOperand(2).getReg();
MachineInstr *DotInstr = MRI.getVRegDef(DotReg);
- if (DotInstr->getOpcode() != TargetOpcode::G_INTRINSIC ||
- cast<GIntrinsic>(DotInstr)->getIntrinsicID() != Intrinsic::spv_fdot)
+ if (DotInstr->getOpcode() != TargetOpcode::G_FMUL &&
+ (DotInstr->getOpcode() != TargetOpcode::G_INTRINSIC ||
+ cast<GIntrinsic>(DotInstr)->getIntrinsicID() != Intrinsic::spv_fdot))
return false;
Register CondZeroReg = CondInstr->getOperand(3).getReg();
@@ -168,8 +169,14 @@ void applySPIRVFaceForward(MachineInstr &MI, MachineRegisterInfo &MRI,
MachineInstr *CondInstr = MRI.getVRegDef(CondReg);
Register DotReg = CondInstr->getOperand(2).getReg();
MachineInstr *DotInstr = MRI.getVRegDef(DotReg);
- Register DotOperand1 = DotInstr->getOperand(2).getReg();
- Register DotOperand2 = DotInstr->getOperand(3).getReg();
+ Register DotOperand1, DotOperand2;
+ if (DotInstr->getOpcode() == TargetOpcode::G_FMUL) {
+ DotOperand1 = DotInstr->getOperand(1).getReg();
+ DotOperand2 = DotInstr->getOperand(2).getReg();
+ } else {
+ DotOperand1 = DotInstr->getOperand(2).getReg();
+ DotOperand2 = DotInstr->getOperand(3).getReg();
+ }
Register TrueReg = MI.getOperand(2).getReg();
// Remove the original `select` instruction.
diff --git a/llvm/test/CodeGen/SPIRV/GlobalISel/InstCombine/prelegalizercombiner-select-to-faceforward.mir b/llvm/test/CodeGen/SPIRV/GlobalISel/InstCombine/prelegalizercombiner-select-to-faceforward.mir
index 4fbc3d0735b68..08f03942460ba 100644
--- a/llvm/test/CodeGen/SPIRV/GlobalISel/InstCombine/prelegalizercombiner-select-to-faceforward.mir
+++ b/llvm/test/CodeGen/SPIRV/GlobalISel/InstCombine/prelegalizercombiner-select-to-faceforward.mir
@@ -1,6 +1,35 @@
# RUN: llc -verify-machineinstrs -O0 -mtriple spirv-unknown-unknown -run-pass=spirv-prelegalizer-combiner %s -o - | FileCheck %s
# REQUIRES: asserts
---
+name: faceforward_instcombine_float
+tracksRegLiveness: true
+legalized: true
+body: |
+ bb.1.entry:
+ ; CHECK-LABEL: name: faceforward_instcombine_float
+ ; CHECK-NOT: %9:_(s32) = G_FCONSTANT float 0.000000e+00
+ ; CHECK-NOT: %8:_(s32) = G_FMUL %1:fid, %2:fid
+ ; CHECK-NOT: %10:_(s1) = G_FCMP floatpred(olt), %8:_(s32), %9:_
+ ; CHECK-NOT: %11:_(s32) = G_FNEG %0:fid
+ ; CHECK-NOT: %12:id(s32) = G_SELECT %10:_(s1), %0:fid, %11:_
+ ; CHECK: %10:id(s32) = G_INTRINSIC intrinsic(@llvm.spv.faceforward), %2(s32), %3(s32), %4(s32)
+ %3:type(s64) = OpTypeFloat 32
+ %5:type(s64) = OpTypeFunction %3:type(s64), %3:type(s64), %3:type(s64), %3:type(s64)
+ OpName %0:fid(s32), 97
+ OpName %1:fid(s32), 98
+ OpName %2:fid(s32), 99
+ %4:iid(s64) = OpFunction %3:type(s64), 0, %5:type(s64)
+ %0:fid(s32) = OpFunctionParameter %3:type(s64)
+ %1:fid(s32) = OpFunctionParameter %3:type(s64)
+ %2:fid(s32) = OpFunctionParameter %3:type(s64)
+ OpName %4:iid(s64), 1701011814, 2003988326, 1600418401, 1953721961, 1651339107, 1600482921, 1634692198, 116
+ %9:_(s32) = G_FCONSTANT float 0.000000e+00
+ %8:_(s32) = G_FMUL %1:fid, %2:fid
+ %10:_(s1) = G_FCMP floatpred(olt), %8:_(s32), %9:_
+ %11:_(s32) = G_FNEG %0:fid
+ %12:id(s32) = G_SELECT %10:_(s1), %0:fid, %11:_
+ OpReturnValue %12:id(s32)
+---
name: faceforward_instcombine_float4
tracksRegLiveness: true
legalized: true
diff --git a/llvm/test/CodeGen/SPIRV/hlsl-intrinsics/faceforward.ll b/llvm/test/CodeGen/SPIRV/hlsl-intrinsics/faceforward.ll
index f181be8ee1200..6811f95bbab17 100644
--- a/llvm/test/CodeGen/SPIRV/hlsl-intrinsics/faceforward.ll
+++ b/llvm/test/CodeGen/SPIRV/hlsl-intrinsics/faceforward.ll
@@ -53,6 +53,20 @@ entry:
ret <4 x float> %spv.faceforward
}
+define internal noundef float @faceforward_instcombine_float(float noundef %a, float noundef %b, float noundef %c) {
+entry:
+ ; CHECK: %[[#]] = OpFunction %[[#float_32]] None %[[#]]
+ ; CHECK: %[[#arg0:]] = OpFunctionParameter %[[#float_32]]
+ ; CHECK: %[[#arg1:]] = OpFunctionParameter %[[#float_32]]
+ ; CHECK: %[[#arg2:]] = OpFunctionParameter %[[#float_32]]
+ ; CHECK: %[[#]] = OpExtInst %[[#float_32]] %[[#op_ext_glsl]] FaceForward %[[#arg0]] %[[#arg1]] %[[#arg2]]
+ %fmul= fmul float %b, %c
+ %fcmp = fcmp olt float %fmul, 0.000000e+00
+ %fneg = fneg float %a
+ %select = select i1 %fcmp, float %a, float %fneg
+ ret float %select
+ }
+
define internal noundef <4 x float> @faceforward_instcombine_float4(<4 x float> noundef %a, <4 x float> noundef %b, <4 x float> noundef %c) {
entry:
; CHECK: %[[#]] = OpFunction %[[#vec4_float_32]] None %[[#]]
>From 5cb68c5498935017eceed5bd71f0afde185bdbf8 Mon Sep 17 00:00:00 2001
From: kmpeng <kaitlinpeng at microsoft.com>
Date: Fri, 16 May 2025 16:51:35 -0700
Subject: [PATCH 5/5] partially address PR comments
---
.../SPIRV/SPIRVPreLegalizerCombiner.cpp | 20 +++++++++++++++----
...egalizercombiner-select-to-faceforward.mir | 4 +++-
2 files changed, 19 insertions(+), 5 deletions(-)
diff --git a/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp b/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp
index 82c5cbf75b849..732945645ed85 100644
--- a/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp
+++ b/llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp
@@ -127,7 +127,13 @@ void applySPIRVDistance(MachineInstr &MI, MachineRegisterInfo &MRI,
/// (vXf32 (g_intrinsic faceforward
/// (vXf32 N) (vXf32 I) (vXf32 Ng)))
///
+/// This only works for Vulkan targets.
+///
bool matchSelectToFaceForward(MachineInstr &MI, MachineRegisterInfo &MRI) {
+ const SPIRVSubtarget &ST = MI.getMF()->getSubtarget<SPIRVSubtarget>();
+ if (!ST.isVulkanEnv())
+ return false;
+
if (MI.getOpcode() != TargetOpcode::G_SELECT)
return false;
@@ -139,10 +145,16 @@ bool matchSelectToFaceForward(MachineInstr &MI, MachineRegisterInfo &MRI) {
Register DotReg = CondInstr->getOperand(2).getReg();
MachineInstr *DotInstr = MRI.getVRegDef(DotReg);
- if (DotInstr->getOpcode() != TargetOpcode::G_FMUL &&
- (DotInstr->getOpcode() != TargetOpcode::G_INTRINSIC ||
- cast<GIntrinsic>(DotInstr)->getIntrinsicID() != Intrinsic::spv_fdot))
- return false;
+ if ((DotInstr->getOpcode() != TargetOpcode::G_INTRINSIC ||
+ cast<GIntrinsic>(DotInstr)->getIntrinsicID() != Intrinsic::spv_fdot)) {
+ if (DotInstr->getOpcode() != TargetOpcode::G_FMUL)
+ return false;
+ Register DotOperand1 = DotInstr->getOperand(1).getReg();
+ Register DotOperand2 = DotInstr->getOperand(2).getReg();
+ if (MRI.getType(DotOperand1).isVector() ||
+ MRI.getType(DotOperand2).isVector())
+ return false;
+ }
Register CondZeroReg = CondInstr->getOperand(3).getReg();
MachineInstr *CondZeroInstr = MRI.getVRegDef(CondZeroReg);
diff --git a/llvm/test/CodeGen/SPIRV/GlobalISel/InstCombine/prelegalizercombiner-select-to-faceforward.mir b/llvm/test/CodeGen/SPIRV/GlobalISel/InstCombine/prelegalizercombiner-select-to-faceforward.mir
index 08f03942460ba..dc7cc03e11613 100644
--- a/llvm/test/CodeGen/SPIRV/GlobalISel/InstCombine/prelegalizercombiner-select-to-faceforward.mir
+++ b/llvm/test/CodeGen/SPIRV/GlobalISel/InstCombine/prelegalizercombiner-select-to-faceforward.mir
@@ -13,6 +13,7 @@ body: |
; CHECK-NOT: %11:_(s32) = G_FNEG %0:fid
; CHECK-NOT: %12:id(s32) = G_SELECT %10:_(s1), %0:fid, %11:_
; CHECK: %10:id(s32) = G_INTRINSIC intrinsic(@llvm.spv.faceforward), %2(s32), %3(s32), %4(s32)
+ ; CHECK: OpReturnValue %10(s32)
%3:type(s64) = OpTypeFloat 32
%5:type(s64) = OpTypeFunction %3:type(s64), %3:type(s64), %3:type(s64), %3:type(s64)
OpName %0:fid(s32), 97
@@ -42,6 +43,7 @@ body: |
; CHECK-NOT: %12:_(<4 x s32>) = G_FNEG %0:vfid
; CHECK-NOT: %13:id(<4 x s32>) = G_SELECT %11:_(s1), %0:vfid, %12:_
; CHECK: %11:id(<4 x s32>) = G_INTRINSIC intrinsic(@llvm.spv.faceforward), %3(<4 x s32>), %4(<4 x s32>), %5(<4 x s32>)
+ ; CHECK: OpReturnValue %11(<4 x s32>)
%4:type(s64) = OpTypeVector %3:type(s64), 4
%6:type(s64) = OpTypeFunction %4:type(s64), %4:type(s64), %4:type(s64), %4:type(s64)
%3:type(s64) = OpTypeFloat 32
@@ -60,4 +62,4 @@ body: |
%12:_(<4 x s32>) = G_FNEG %0:vfid
%13:id(<4 x s32>) = G_SELECT %11:_(s1), %0:vfid, %12:_
OpReturnValue %13:id(<4 x s32>)
-
\ No newline at end of file
+
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