Callee->getAttributes());
}
+ // pow(exp(x), y) -> exp(x*y)
+ // pow(exp2(x), y) -> exp2(x * y)
+ // We enable these only under fast-math. Besides rounding
+ // differences the transformation changes overflow and
+ // underflow behavior quite dramatically.
+ // Example: x = 1000, y = 0.001.
+ // pow(exp(x), y) = pow(inf, 0.001) = inf, whereas exp(x*y) = exp(1).
+ if (canUseUnsafeFPMath(CI->getParent()->getParent())) {
+ if (auto *OpC = dyn_cast<CallInst>(Op1)) {
+ IRBuilder<>::FastMathFlagGuard Guard(B);
+ FastMathFlags FMF;
+ FMF.setUnsafeAlgebra();
+ B.SetFastMathFlags(FMF);
+
+ LibFunc::Func Func;
+ Function *Callee = OpC->getCalledFunction();
+ StringRef FuncName = Callee->getName();
+
+ if (TLI->getLibFunc(FuncName, Func) && TLI->has(Func) &&
+ (Func == LibFunc::exp || Func == LibFunc::exp2))
+ return EmitUnaryFloatFnCall(
+ B.CreateFMul(OpC->getArgOperand(0), Op2, "mul"), FuncName, B,
+ Callee->getAttributes());
+ }
+ }
+
ConstantFP *Op2C = dyn_cast<ConstantFP>(Op2);
if (!Op2C)
return Ret;