diff options
| -rw-r--r-- | llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp | 10 | ||||
| -rw-r--r-- | llvm/test/Transforms/InstCombine/log-pow-nofastmath.ll | 13 | ||||
| -rw-r--r-- | llvm/test/Transforms/InstCombine/log-pow.ll | 13 |
3 files changed, 35 insertions, 1 deletions
diff --git a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp index 47e587fab7b..83afb1a65ac 100644 --- a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp +++ b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp @@ -1322,6 +1322,15 @@ Value *LibCallSimplifier::optimizeLog(CallInst *CI, IRBuilder<> &B) { return B.CreateFMul(OpC->getArgOperand(1), EmitUnaryFloatFnCall(OpC->getOperand(0), Callee->getName(), B, Callee->getAttributes()), "mul"); + + // log(exp2(y)) -> y*log(2) + if (F && Name == "log" && TLI->getLibFunc(F->getName(), Func) && + TLI->has(Func) && Func == LibFunc::exp2) + return B.CreateFMul( + OpC->getArgOperand(0), + EmitUnaryFloatFnCall(ConstantFP::get(CI->getType(), 2.0), + Callee->getName(), B, Callee->getAttributes()), + "logmul"); return Ret; } @@ -2301,7 +2310,6 @@ void LibCallSimplifier::replaceAllUsesWith(Instruction *I, Value *With) { // log, logf, logl: // * log(exp(x)) -> x // * log(exp(y)) -> y*log(e) -// * log(exp2(y)) -> y*log(2) // * log(exp10(y)) -> y*log(10) // * log(sqrt(x)) -> 0.5*log(x) // diff --git a/llvm/test/Transforms/InstCombine/log-pow-nofastmath.ll b/llvm/test/Transforms/InstCombine/log-pow-nofastmath.ll index 0811e63cc74..6c37c5466ce 100644 --- a/llvm/test/Transforms/InstCombine/log-pow-nofastmath.ll +++ b/llvm/test/Transforms/InstCombine/log-pow-nofastmath.ll @@ -13,5 +13,18 @@ entry: ; CHECK: ret double %call ; CHECK: } +define double @test3(double %x) #0 { + %call2 = call double @exp2(double %x) #0 + %call3 = call double @log(double %call2) #0 + ret double %call3 +} + +; CHECK-LABEL: @test3 +; CHECK: %call2 = call double @exp2(double %x) +; CHECK: %call3 = call double @log(double %call2) +; CHECK: ret double %call3 +; CHECK: } + declare double @log(double) #0 +declare double @exp2(double) declare double @llvm.pow.f64(double, double) diff --git a/llvm/test/Transforms/InstCombine/log-pow.ll b/llvm/test/Transforms/InstCombine/log-pow.ll index c98a1a5bc62..1acd0354431 100644 --- a/llvm/test/Transforms/InstCombine/log-pow.ll +++ b/llvm/test/Transforms/InstCombine/log-pow.ll @@ -22,7 +22,20 @@ define double @test2(double ()* %fptr, double %p1) #0 { ; CHECK-LABEL: @test2 ; CHECK: log +define double @test3(double %x) #0 { + %call2 = call double @exp2(double %x) #0 + %call3 = call double @log(double %call2) #0 + ret double %call3 +} + +; CHECK-LABEL: @test3 +; CHECK: %call2 = call double @exp2(double %x) #0 +; CHECK: %logmul = fmul fast double %x, 0x3FE62E42FEFA39EF +; CHECK: ret double %logmul +; CHECK: } + declare double @log(double) #0 +declare double @exp2(double) #0 declare double @llvm.pow.f64(double, double) attributes #0 = { "unsafe-fp-math"="true" } |
