[clang] [libc] [libc][math] fix-exp (PR #148670)

[Muhammad Bassiouni via cfe-commits]

https://github.com/bassiounix updated https://github.com/llvm/llvm-project/pull/148670

>From 30f3a33cea2cfcbe61663102d47dcc74ff43ccb3 Mon Sep 17 00:00:00 2001
From: bassiounix <muhammad.m.bassiouni at gmail.com>
Date: Mon, 14 Jul 2025 19:50:42 +0300
Subject: [PATCH 1/2] [libc][math] fix-exp

---
 libc/src/__support/FPUtil/PolyEval.h     | 8 ++++----
 libc/src/__support/FPUtil/multiply_add.h | 8 ++++----
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/libc/src/__support/FPUtil/PolyEval.h b/libc/src/__support/FPUtil/PolyEval.h
index 41104620ed61d..105b3f2698897 100644
--- a/libc/src/__support/FPUtil/PolyEval.h
+++ b/libc/src/__support/FPUtil/PolyEval.h
@@ -25,19 +25,19 @@ namespace LIBC_NAMESPACE_DECL {
 namespace fputil {
 
 template <typename T>
-LIBC_INLINE cpp::enable_if_t<(sizeof(T) > sizeof(void *)), T>
+LIBC_INLINE static constexpr cpp::enable_if_t<(sizeof(T) > sizeof(void *)), T>
 polyeval(const T &, const T &a0) {
   return a0;
 }
 
 template <typename T>
-LIBC_INLINE cpp::enable_if_t<(sizeof(T) <= sizeof(void *)), T> polyeval(T,
-                                                                        T a0) {
+LIBC_INLINE static constexpr cpp::enable_if_t<(sizeof(T) <= sizeof(void *)), T>
+polyeval(T, T a0) {
   return a0;
 }
 
 template <typename T, typename... Ts>
-LIBC_INLINE cpp::enable_if_t<(sizeof(T) > sizeof(void *)), T>
+LIBC_INLINE static constexpr cpp::enable_if_t<(sizeof(T) > sizeof(void *)), T>
 polyeval(const T &x, const T &a0, const Ts &...a) {
   return multiply_add(x, polyeval(x, a...), a0);
 }
diff --git a/libc/src/__support/FPUtil/multiply_add.h b/libc/src/__support/FPUtil/multiply_add.h
index 8260702e2c9f4..5f759f86227cb 100644
--- a/libc/src/__support/FPUtil/multiply_add.h
+++ b/libc/src/__support/FPUtil/multiply_add.h
@@ -23,13 +23,13 @@ namespace fputil {
 // which uses FMA instructions to speed up if available.
 
 template <typename T>
-LIBC_INLINE cpp::enable_if_t<(sizeof(T) > sizeof(void *)), T>
+LIBC_INLINE static constexpr cpp::enable_if_t<(sizeof(T) > sizeof(void *)), T>
 multiply_add(const T &x, const T &y, const T &z) {
   return x * y + z;
 }
 
 template <typename T>
-LIBC_INLINE cpp::enable_if_t<(sizeof(T) <= sizeof(void *)), T>
+LIBC_INLINE static constexpr cpp::enable_if_t<(sizeof(T) <= sizeof(void *)), T>
 multiply_add(T x, T y, T z) {
   return x * y + z;
 }
@@ -47,7 +47,7 @@ namespace LIBC_NAMESPACE_DECL {
 namespace fputil {
 
 #ifdef LIBC_TARGET_CPU_HAS_FMA_FLOAT
-LIBC_INLINE float multiply_add(float x, float y, float z) {
+LIBC_INLINE static constexpr float multiply_add(float x, float y, float z) {
 #if __has_builtin(__builtin_elementwise_fma)
   return __builtin_elementwise_fma(x, y, z);
 #else
@@ -57,7 +57,7 @@ LIBC_INLINE float multiply_add(float x, float y, float z) {
 #endif // LIBC_TARGET_CPU_HAS_FMA_FLOAT
 
 #ifdef LIBC_TARGET_CPU_HAS_FMA_DOUBLE
-LIBC_INLINE double multiply_add(double x, double y, double z) {
+LIBC_INLINE static constexpr double multiply_add(double x, double y, double z) {
 #if __has_builtin(__builtin_elementwise_fma)
   return __builtin_elementwise_fma(x, y, z);
 #else

>From c7311382041e08bbd2fe53d64bc809cde6831f10 Mon Sep 17 00:00:00 2001
From: bassiounix <muhammad.m.bassiouni at gmail.com>
Date: Mon, 14 Jul 2025 20:23:08 +0300
Subject: [PATCH 2/2] make builtins constexpr

---
 clang/lib/CodeGen/CGBuiltin.cpp | 4 ++--
 clang/lib/CodeGen/CGBuiltin.h   | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 5f2eb76e7bacb..506654d01f64e 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -602,7 +602,7 @@ Value *emitUnaryMaybeConstrainedFPBuiltin(CodeGenFunction &CGF,
 
 // Emit an intrinsic that has 2 operands of the same type as its result.
 // Depending on mode, this may be a constrained floating-point intrinsic.
-static Value *emitBinaryMaybeConstrainedFPBuiltin(CodeGenFunction &CGF,
+static constexpr Value *emitBinaryMaybeConstrainedFPBuiltin(CodeGenFunction &CGF,
                                 const CallExpr *E, unsigned IntrinsicID,
                                 unsigned ConstrainedIntrinsicID) {
   llvm::Value *Src0 = CGF.EmitScalarExpr(E->getArg(0));
@@ -640,7 +640,7 @@ emitBinaryExpMaybeConstrainedFPBuiltin(CodeGenFunction &CGF, const CallExpr *E,
 
 // Emit an intrinsic that has 3 operands of the same type as its result.
 // Depending on mode, this may be a constrained floating-point intrinsic.
-static Value *emitTernaryMaybeConstrainedFPBuiltin(CodeGenFunction &CGF,
+static constexpr Value *emitTernaryMaybeConstrainedFPBuiltin(CodeGenFunction &CGF,
                                  const CallExpr *E, unsigned IntrinsicID,
                                  unsigned ConstrainedIntrinsicID) {
   llvm::Value *Src0 = CGF.EmitScalarExpr(E->getArg(0));
diff --git a/clang/lib/CodeGen/CGBuiltin.h b/clang/lib/CodeGen/CGBuiltin.h
index 667bce845f5c0..aafc78ce77dff 100644
--- a/clang/lib/CodeGen/CGBuiltin.h
+++ b/clang/lib/CodeGen/CGBuiltin.h
@@ -60,7 +60,7 @@ enum class clang::CodeGen::CodeGenFunction::MSVCIntrin {
 // matching the argument type. It is assumed that only the first argument is
 // overloaded.
 template <unsigned N>
-llvm::Value *emitBuiltinWithOneOverloadedType(clang::CodeGen::CodeGenFunction &CGF,
+static constexpr llvm::Value *emitBuiltinWithOneOverloadedType(clang::CodeGen::CodeGenFunction &CGF,
                                               const clang::CallExpr *E,
                                               unsigned IntrinsicID,
                                               llvm::StringRef Name = "") {