instcombine: Migrate isascii optimizations
This patch migrates the isascii optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168579 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Utils/SimplifyLibCalls.cpp b/lib/Transforms/Utils/SimplifyLibCalls.cpp
index 1320f70..2b390c1 100644
--- a/lib/Transforms/Utils/SimplifyLibCalls.cpp
+++ b/lib/Transforms/Utils/SimplifyLibCalls.cpp
@@ -1283,6 +1283,21 @@
}
};
+struct IsAsciiOpt : public LibCallOptimization {
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ FunctionType *FT = Callee->getFunctionType();
+ // We require integer(i32)
+ if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
+ !FT->getParamType(0)->isIntegerTy(32))
+ return 0;
+
+ // isascii(c) -> c <u 128
+ Value *Op = CI->getArgOperand(0);
+ Op = B.CreateICmpULT(Op, B.getInt32(128), "isascii");
+ return B.CreateZExt(Op, CI->getType());
+ }
+};
+
} // End anonymous namespace.
namespace llvm {
@@ -1333,6 +1348,7 @@
FFSOpt FFS;
AbsOpt Abs;
IsDigitOpt IsDigit;
+ IsAsciiOpt IsAscii;
void initOptimizations();
void addOpt(LibFunc::Func F, LibCallOptimization* Opt);
@@ -1452,6 +1468,7 @@
addOpt(LibFunc::labs, &Abs);
addOpt(LibFunc::llabs, &Abs);
addOpt(LibFunc::isdigit, &IsDigit);
+ addOpt(LibFunc::isascii, &IsAscii);
}
Value *LibCallSimplifierImpl::optimizeCall(CallInst *CI) {