instcombine: Migrate isdigit optimizations
This patch migrates the isdigit optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168578 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Utils/SimplifyLibCalls.cpp b/lib/Transforms/Utils/SimplifyLibCalls.cpp
index ec98e93..1320f70 100644
--- a/lib/Transforms/Utils/SimplifyLibCalls.cpp
+++ b/lib/Transforms/Utils/SimplifyLibCalls.cpp
@@ -1267,6 +1267,22 @@
}
};
+struct IsDigitOpt : 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;
+
+ // isdigit(c) -> (c-'0') <u 10
+ Value *Op = CI->getArgOperand(0);
+ Op = B.CreateSub(Op, B.getInt32('0'), "isdigittmp");
+ Op = B.CreateICmpULT(Op, B.getInt32(10), "isdigit");
+ return B.CreateZExt(Op, CI->getType());
+ }
+};
+
} // End anonymous namespace.
namespace llvm {
@@ -1316,6 +1332,7 @@
// Integer library call optimizations.
FFSOpt FFS;
AbsOpt Abs;
+ IsDigitOpt IsDigit;
void initOptimizations();
void addOpt(LibFunc::Func F, LibCallOptimization* Opt);
@@ -1434,6 +1451,7 @@
addOpt(LibFunc::abs, &Abs);
addOpt(LibFunc::labs, &Abs);
addOpt(LibFunc::llabs, &Abs);
+ addOpt(LibFunc::isdigit, &IsDigit);
}
Value *LibCallSimplifierImpl::optimizeCall(CallInst *CI) {