[InstCombine] Missed optimization in math expression: sin(x) / cos(x) => tan(x)

Summary: This patch enables folding sin(x) / cos(x) -> tan(x), cos(x) / sin(x) -> 1 / tan(x) under -ffast-math flag

Reviewers: hfinkel, spatel

Reviewed By: spatel

Subscribers: andrew.w.kaylor, efriedma, scanon, llvm-commits

Differential Revision: https://reviews.llvm.org/D41286

llvm-svn: 322255

2 files changed, 13 insertions, 15 deletions

diff --git a/llvm/lib/Transforms/Utils/BuildLibCalls.cpp b/llvm/lib/Transforms/Utils/BuildLibCalls.cpp
index b60dfb4f354..d4cf03c326d 100644
--- a/llvm/lib/Transforms/Utils/BuildLibCalls.cpp
+++ b/llvm/lib/Transforms/Utils/BuildLibCalls.cpp
@@ -709,6 +709,19 @@ bool llvm::inferLibFuncAttributes(Function &F, const TargetLibraryInfo &TLI) {
   }
 }
 
+bool llvm::hasUnaryFloatFn(const TargetLibraryInfo *TLI, Type *Ty,
+                           LibFunc DoubleFn, LibFunc FloatFn,
+                           LibFunc LongDoubleFn) {
+  switch (Ty->getTypeID()) {
+  case Type::FloatTyID:
+    return TLI->has(FloatFn);
+  case Type::DoubleTyID:
+    return TLI->has(DoubleFn);
+  default:
+    return TLI->has(LongDoubleFn);
+  }
+}
+
 //- Emit LibCalls ------------------------------------------------------------//
 
 Value *llvm::castToCStr(Value *V, IRBuilder<> &B) {
diff --git a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
index 03a1d55ddc3..dcdff3e96b3 100644
--- a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
+++ b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
@@ -104,21 +104,6 @@ static bool callHasFloatingPointArgument(const CallInst *CI) {
   });
 }
 
-/// \brief Check whether the overloaded unary floating point function
-/// corresponding to \a Ty is available.
-static bool hasUnaryFloatFn(const TargetLibraryInfo *TLI, Type *Ty,
-                            LibFunc DoubleFn, LibFunc FloatFn,
-                            LibFunc LongDoubleFn) {
-  switch (Ty->getTypeID()) {
-  case Type::FloatTyID:
-    return TLI->has(FloatFn);
-  case Type::DoubleTyID:
-    return TLI->has(DoubleFn);
-  default:
-    return TLI->has(LongDoubleFn);
-  }
-}
-
 //===----------------------------------------------------------------------===//
 // String and Memory Library Call Optimizations
 //===----------------------------------------------------------------------===//