Turn cos(-x) into cos(x). Patch by Alexander Malyshev!

llvm-svn: 147291
This commit is contained in:
Nick Lewycky 2011-12-27 18:25:50 +00:00
parent c64fcf4a95
commit f4c21901a3
2 changed files with 41 additions and 5 deletions

View File

@ -840,6 +840,28 @@ struct MemSetOpt : public LibCallOptimization {
// Math Library Optimizations
//===----------------------------------------------------------------------===//
//===---------------------------------------===//
// 'cos*' Optimizations
struct CosOpt : public LibCallOptimization {
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
FunctionType *FT = Callee->getFunctionType();
// Just make sure this has 1 argument of FP type, which matches the
// result type.
if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
!FT->getParamType(0)->isFloatingPointTy())
return 0;
// cos(-x) -> cos(x)
Value *Op1 = CI->getArgOperand(0);
if (BinaryOperator::isFNeg(Op1)) {
BinaryOperator *BinExpr = cast<BinaryOperator>(Op1);
return B.CreateCall(Callee, BinExpr->getOperand(1), "cos");
}
return 0;
}
};
//===---------------------------------------===//
// 'pow*' Optimizations
@ -870,7 +892,7 @@ struct PowOpt : public LibCallOptimization {
if (Op2C->isExactlyValue(0.5)) {
// Expand pow(x, 0.5) to (x == -infinity ? +infinity : fabs(sqrt(x))).
// This is faster than calling pow, and still handles negative zero
// and negative infinite correctly.
// and negative infinity correctly.
// TODO: In fast-math mode, this could be just sqrt(x).
// TODO: In finite-only mode, this could be just fabs(sqrt(x)).
Value *Inf = ConstantFP::getInfinity(CI->getType());
@ -1455,7 +1477,7 @@ namespace {
StrToOpt StrTo; StrSpnOpt StrSpn; StrCSpnOpt StrCSpn; StrStrOpt StrStr;
MemCmpOpt MemCmp; MemCpyOpt MemCpy; MemMoveOpt MemMove; MemSetOpt MemSet;
// Math Library Optimizations
PowOpt Pow; Exp2Opt Exp2; UnaryDoubleFPOpt UnaryDoubleFP;
CosOpt Cos; PowOpt Pow; Exp2Opt Exp2; UnaryDoubleFPOpt UnaryDoubleFP;
// Integer Optimizations
FFSOpt FFS; AbsOpt Abs; IsDigitOpt IsDigit; IsAsciiOpt IsAscii;
ToAsciiOpt ToAscii;
@ -1539,6 +1561,9 @@ void SimplifyLibCalls::InitOptimizations() {
Optimizations["__strcpy_chk"] = &StrCpyChk;
// Math Library Optimizations
Optimizations["cosf"] = &Cos;
Optimizations["cos"] = &Cos;
Optimizations["cosl"] = &Cos;
Optimizations["powf"] = &Pow;
Optimizations["pow"] = &Pow;
Optimizations["powl"] = &Pow;
@ -2352,9 +2377,6 @@ bool SimplifyLibCalls::doInitialization(Module &M) {
// * cbrt(sqrt(x)) -> pow(x,1/6)
// * cbrt(sqrt(x)) -> pow(x,1/9)
//
// cos, cosf, cosl:
// * cos(-x) -> cos(x)
//
// exp, expf, expl:
// * exp(log(x)) -> x
//

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@ -0,0 +1,14 @@
; RUN: opt < %s -simplify-libcalls -S | FileCheck %s
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
define double @foo(double %d) nounwind readnone {
; CHECK: @foo
%1 = fsub double -0.000000e+00, %d
%2 = call double @cos(double %1) nounwind readnone
; CHECK: call double @cos(double %d)
ret double %2
}
declare double @cos(double) nounwind readnone