[clang] [Clang] VectorExprEvaluator::VisitCallExpr / InterpretBuiltin - allow insertps intrinsic to be used in constexp (PR #165513)
Ahmed Nour via cfe-commits
cfe-commits at lists.llvm.org
Wed Oct 29 00:36:25 PDT 2025
https://github.com/ahmednoursphinx updated https://github.com/llvm/llvm-project/pull/165513
>From eca52c0e1d9e79911f79d7339926e295fcbcf84f Mon Sep 17 00:00:00 2001
From: ahmed <ahmednour.mohamed2012 at gmail.com>
Date: Tue, 28 Oct 2025 23:49:56 +0300
Subject: [PATCH 1/2] feat: VectorExprEvaluator::VisitCallExpr /
InterpretBuiltin - Allow insertps intrinsic to be used in constexpr
---
clang/include/clang/Basic/BuiltinsX86.td | 5 ++-
clang/lib/AST/ByteCode/InterpBuiltin.cpp | 40 +++++++++++++++++++++---
clang/lib/AST/ExprConstant.cpp | 39 ++++++++++++++++++++---
clang/test/CodeGen/X86/sse41-builtins.c | 10 ++++++
4 files changed, 85 insertions(+), 9 deletions(-)
diff --git a/clang/include/clang/Basic/BuiltinsX86.td b/clang/include/clang/Basic/BuiltinsX86.td
index 0c85e280e748b..a431fc36b41c1 100644
--- a/clang/include/clang/Basic/BuiltinsX86.td
+++ b/clang/include/clang/Basic/BuiltinsX86.td
@@ -327,8 +327,11 @@ let Features = "ssse3", Attributes = [NoThrow, Const, Constexpr, RequiredVectorW
}
}
-let Features = "sse4.1", Attributes = [NoThrow, Const, RequiredVectorWidth<128>] in {
+let Features = "sse4.1", Attributes = [NoThrow, Const, Constexpr, RequiredVectorWidth<128>] in {
def insertps128 : X86Builtin<"_Vector<4, float>(_Vector<4, float>, _Vector<4, float>, _Constant char)">;
+}
+
+let Features = "sse4.1", Attributes = [NoThrow, Const, RequiredVectorWidth<128>] in {
def roundps : X86Builtin<"_Vector<4, float>(_Vector<4, float>, _Constant int)">;
def roundss : X86Builtin<"_Vector<4, float>(_Vector<4, float>, _Vector<4, float>, _Constant int)">;
def roundsd : X86Builtin<"_Vector<2, double>(_Vector<2, double>, _Vector<2, double>, _Constant int)">;
diff --git a/clang/lib/AST/ByteCode/InterpBuiltin.cpp b/clang/lib/AST/ByteCode/InterpBuiltin.cpp
index 8f23001ea5a39..b1f0832860476 100644
--- a/clang/lib/AST/ByteCode/InterpBuiltin.cpp
+++ b/clang/lib/AST/ByteCode/InterpBuiltin.cpp
@@ -3358,7 +3358,8 @@ static bool interp__builtin_x86_byteshift(
static bool interp__builtin_ia32_shuffle_generic(
InterpState &S, CodePtr OpPC, const CallExpr *Call,
llvm::function_ref<std::pair<unsigned, unsigned>(unsigned, unsigned)>
- GetSourceIndex) {
+ GetSourceIndex,
+ llvm::function_ref<bool(unsigned, unsigned)> ShouldZero = nullptr) {
assert(Call->getNumArgs() == 3);
unsigned ShuffleMask = popToAPSInt(S, Call->getArg(2)).getZExtValue();
@@ -3373,9 +3374,20 @@ static bool interp__builtin_ia32_shuffle_generic(
const Pointer &Dst = S.Stk.peek<Pointer>();
for (unsigned DstIdx = 0; DstIdx != NumElems; ++DstIdx) {
- auto [SrcVecIdx, SrcIdx] = GetSourceIndex(DstIdx, ShuffleMask);
- const Pointer &Src = (SrcVecIdx == 0) ? A : B;
- TYPE_SWITCH(ElemT, { Dst.elem<T>(DstIdx) = Src.elem<T>(SrcIdx); });
+ if (ShouldZero && ShouldZero(DstIdx, ShuffleMask)) {
+ // Zero out this element
+ if (ElemT == PT_Float) {
+ Dst.elem<Floating>(DstIdx) = Floating(S.getASTContext().getFloatTypeSemantics(VecT->getElementType()));
+ } else {
+ INT_TYPE_SWITCH_NO_BOOL(ElemT, {
+ Dst.elem<T>(DstIdx) = T::from(0);
+ });
+ }
+ } else {
+ auto [SrcVecIdx, SrcIdx] = GetSourceIndex(DstIdx, ShuffleMask);
+ const Pointer &Src = (SrcVecIdx == 0) ? A : B;
+ TYPE_SWITCH(ElemT, { Dst.elem<T>(DstIdx) = Src.elem<T>(SrcIdx); });
+ }
}
Dst.initializeAllElements();
@@ -4348,6 +4360,26 @@ bool InterpretBuiltin(InterpState &S, CodePtr OpPC, const CallExpr *Call,
unsigned Index = (ShuffleMask >> BitIndex) & IndexMask;
return std::pair<unsigned, unsigned>{SrcIdx, LaneOffset + Index};
});
+ case X86::BI__builtin_ia32_insertps128:
+ return interp__builtin_ia32_shuffle_generic(
+ S, OpPC, Call,
+ [](unsigned DstIdx, unsigned Mask) {
+ // Bits [7:6]: select element from source vector Y (0-3)
+ // Bits [5:4]: select destination position (0-3)
+ unsigned SrcElem = (Mask >> 6) & 0x3;
+ unsigned DstElem = (Mask >> 4) & 0x3;
+ if (DstIdx == DstElem) {
+ // Insert element from source vector (B) at this position
+ return std::pair<unsigned, unsigned>{1, SrcElem};
+ } else {
+ // Copy from destination vector (A)
+ return std::pair<unsigned, unsigned>{0, DstIdx};
+ }
+ },
+ [](unsigned DstIdx, unsigned Mask) {
+ // Bits [3:0]: zero mask
+ return (Mask & (1 << DstIdx)) != 0;
+ });
case X86::BI__builtin_ia32_pshufb128:
case X86::BI__builtin_ia32_pshufb256:
case X86::BI__builtin_ia32_pshufb512:
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index 29ee089505125..17c966b8c9f4c 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -11622,7 +11622,8 @@ static bool evalPackBuiltin(const CallExpr *E, EvalInfo &Info, APValue &Result,
static bool evalShuffleGeneric(
EvalInfo &Info, const CallExpr *Call, APValue &Out,
llvm::function_ref<std::pair<unsigned, unsigned>(unsigned, unsigned)>
- GetSourceIndex) {
+ GetSourceIndex,
+ llvm::function_ref<bool(unsigned, unsigned)> ShouldZero = nullptr) {
const auto *VT = Call->getType()->getAs<VectorType>();
if (!VT)
@@ -11643,9 +11644,15 @@ static bool evalShuffleGeneric(
ResultElements.reserve(NumElts);
for (unsigned DstIdx = 0; DstIdx != NumElts; ++DstIdx) {
- auto [SrcVecIdx, SrcIdx] = GetSourceIndex(DstIdx, ShuffleMask);
- const APValue &Src = (SrcVecIdx == 0) ? A : B;
- ResultElements.push_back(Src.getVectorElt(SrcIdx));
+ if (ShouldZero && ShouldZero(DstIdx, ShuffleMask)) {
+ // Zero out this element
+ QualType ElemTy = VT->getElementType();
+ ResultElements.push_back(APValue(APFloat::getZero(Info.Ctx.getFloatTypeSemantics(ElemTy))));
+ } else {
+ auto [SrcVecIdx, SrcIdx] = GetSourceIndex(DstIdx, ShuffleMask);
+ const APValue &Src = (SrcVecIdx == 0) ? A : B;
+ ResultElements.push_back(Src.getVectorElt(SrcIdx));
+ }
}
Out = APValue(ResultElements.data(), ResultElements.size());
@@ -12481,6 +12488,30 @@ bool VectorExprEvaluator::VisitCallExpr(const CallExpr *E) {
return false;
return Success(R, E);
}
+ case X86::BI__builtin_ia32_insertps128: {
+ APValue R;
+ if (!evalShuffleGeneric(
+ Info, E, R,
+ [](unsigned DstIdx, unsigned Mask) -> std::pair<unsigned, unsigned> {
+ // Bits [7:6]: select element from source vector Y (0-3)
+ // Bits [5:4]: select destination position (0-3)
+ unsigned SrcElem = (Mask >> 6) & 0x3;
+ unsigned DstElem = (Mask >> 4) & 0x3;
+ if (DstIdx == DstElem) {
+ // Insert element from source vector (B) at this position
+ return {1, SrcElem};
+ } else {
+ // Copy from destination vector (A)
+ return {0, DstIdx};
+ }
+ },
+ [](unsigned DstIdx, unsigned Mask) -> bool {
+ // Bits [3:0]: zero mask
+ return (Mask & (1 << DstIdx)) != 0;
+ }))
+ return false;
+ return Success(R, E);
+ }
case X86::BI__builtin_ia32_pshufb128:
case X86::BI__builtin_ia32_pshufb256:
case X86::BI__builtin_ia32_pshufb512: {
diff --git a/clang/test/CodeGen/X86/sse41-builtins.c b/clang/test/CodeGen/X86/sse41-builtins.c
index 62cd392824bb2..35fa65a99836b 100644
--- a/clang/test/CodeGen/X86/sse41-builtins.c
+++ b/clang/test/CodeGen/X86/sse41-builtins.c
@@ -307,6 +307,16 @@ __m128 test_mm_insert_ps(__m128 x, __m128 y) {
return _mm_insert_ps(x, y, 4);
}
+TEST_CONSTEXPR((match_m128(_mm_insert_ps(((__m128)(__v4sf){1.0f, 2.0f, 3.0f, 4.0f}), ((__m128)(__v4sf){10.0f, 20.0f, 30.0f, 40.0f}), 0x10), 1.0f, 10.0f, 3.0f, 4.0f))); // Insert Y[0] into X[1]
+TEST_CONSTEXPR((match_m128(_mm_insert_ps(((__m128)(__v4sf){1.0f, 2.0f, 3.0f, 4.0f}), ((__m128)(__v4sf){10.0f, 20.0f, 30.0f, 40.0f}), 0x00), 10.0f, 2.0f, 3.0f, 4.0f))); // Insert Y[0] into X[0]
+TEST_CONSTEXPR((match_m128(_mm_insert_ps(((__m128)(__v4sf){1.0f, 2.0f, 3.0f, 4.0f}), ((__m128)(__v4sf){10.0f, 20.0f, 30.0f, 40.0f}), 0x20), 1.0f, 2.0f, 10.0f, 4.0f))); // Insert Y[0] into X[2]
+TEST_CONSTEXPR((match_m128(_mm_insert_ps(((__m128)(__v4sf){1.0f, 2.0f, 3.0f, 4.0f}), ((__m128)(__v4sf){10.0f, 20.0f, 30.0f, 40.0f}), 0x30), 1.0f, 2.0f, 3.0f, 10.0f))); // Insert Y[0] into X[3]
+TEST_CONSTEXPR((match_m128(_mm_insert_ps(((__m128)(__v4sf){1.0f, 2.0f, 3.0f, 4.0f}), ((__m128)(__v4sf){10.0f, 20.0f, 30.0f, 40.0f}), 0x80), 30.0f, 2.0f, 3.0f, 4.0f))); // Insert Y[2] into X[0]
+TEST_CONSTEXPR((match_m128(_mm_insert_ps(((__m128)(__v4sf){1.0f, 2.0f, 3.0f, 4.0f}), ((__m128)(__v4sf){10.0f, 20.0f, 30.0f, 40.0f}), 0x01), 0.0f, 2.0f, 3.0f, 4.0f))); // Insert Y[0] into X[0], zero X[0]
+TEST_CONSTEXPR((match_m128(_mm_insert_ps(((__m128)(__v4sf){1.0f, 2.0f, 3.0f, 4.0f}), ((__m128)(__v4sf){10.0f, 20.0f, 30.0f, 40.0f}), 0x0A), 10.0f, 0.0f, 3.0f, 0.0f))); // Insert Y[0] into X[0], zero X[1] and X[3]
+TEST_CONSTEXPR((match_m128(_mm_insert_ps(((__m128)(__v4sf){1.0f, 2.0f, 3.0f, 4.0f}), ((__m128)(__v4sf){10.0f, 20.0f, 30.0f, 40.0f}), 0x0F), 0.0f, 0.0f, 0.0f, 0.0f))); // Insert Y[0] into X[0], zero all
+TEST_CONSTEXPR((match_m128(_mm_insert_ps(((__m128)(__v4sf){1.0f, 2.0f, 3.0f, 4.0f}), ((__m128)(__v4sf){10.0f, 20.0f, 30.0f, 40.0f}), 0xCF), 0.0f, 0.0f, 0.0f, 0.0f))); // Insert Y[3] into X[0], zero all
+
__m128i test_mm_max_epi8(__m128i x, __m128i y) {
// CHECK-LABEL: test_mm_max_epi8
// CHECK: call <16 x i8> @llvm.smax.v16i8(<16 x i8> %{{.*}}, <16 x i8> %{{.*}})
>From 578e7f7152c4ed04c9008d02f17e10b63930840b Mon Sep 17 00:00:00 2001
From: ahmed <ahmednour.mohamed2012 at gmail.com>
Date: Wed, 29 Oct 2025 10:36:13 +0300
Subject: [PATCH 2/2] chore: apply formatting
---
clang/lib/AST/ByteCode/InterpBuiltin.cpp | 7 +++----
clang/lib/AST/ExprConstant.cpp | 6 ++++--
2 files changed, 7 insertions(+), 6 deletions(-)
diff --git a/clang/lib/AST/ByteCode/InterpBuiltin.cpp b/clang/lib/AST/ByteCode/InterpBuiltin.cpp
index c4d92804d9c4a..117b10b1c6c0b 100644
--- a/clang/lib/AST/ByteCode/InterpBuiltin.cpp
+++ b/clang/lib/AST/ByteCode/InterpBuiltin.cpp
@@ -3431,11 +3431,10 @@ static bool interp__builtin_ia32_shuffle_generic(
if (ShouldZero && ShouldZero(DstIdx, ShuffleMask)) {
// Zero out this element
if (ElemT == PT_Float) {
- Dst.elem<Floating>(DstIdx) = Floating(S.getASTContext().getFloatTypeSemantics(VecT->getElementType()));
+ Dst.elem<Floating>(DstIdx) = Floating(
+ S.getASTContext().getFloatTypeSemantics(VecT->getElementType()));
} else {
- INT_TYPE_SWITCH_NO_BOOL(ElemT, {
- Dst.elem<T>(DstIdx) = T::from(0);
- });
+ INT_TYPE_SWITCH_NO_BOOL(ElemT, { Dst.elem<T>(DstIdx) = T::from(0); });
}
} else {
auto [SrcVecIdx, SrcIdx] = GetSourceIndex(DstIdx, ShuffleMask);
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index d27e923949c1f..d406ac52f1121 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -11647,7 +11647,8 @@ static bool evalShuffleGeneric(
if (ShouldZero && ShouldZero(DstIdx, ShuffleMask)) {
// Zero out this element
QualType ElemTy = VT->getElementType();
- ResultElements.push_back(APValue(APFloat::getZero(Info.Ctx.getFloatTypeSemantics(ElemTy))));
+ ResultElements.push_back(
+ APValue(APFloat::getZero(Info.Ctx.getFloatTypeSemantics(ElemTy))));
} else {
auto [SrcVecIdx, SrcIdx] = GetSourceIndex(DstIdx, ShuffleMask);
const APValue &Src = (SrcVecIdx == 0) ? A : B;
@@ -12492,7 +12493,8 @@ bool VectorExprEvaluator::VisitCallExpr(const CallExpr *E) {
APValue R;
if (!evalShuffleGeneric(
Info, E, R,
- [](unsigned DstIdx, unsigned Mask) -> std::pair<unsigned, unsigned> {
+ [](unsigned DstIdx,
+ unsigned Mask) -> std::pair<unsigned, unsigned> {
// Bits [7:6]: select element from source vector Y (0-3)
// Bits [5:4]: select destination position (0-3)
unsigned SrcElem = (Mask >> 6) & 0x3;
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