instcombine: Migrate fprintf optimizations
This patch migrates the fprintf optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168891 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Utils/SimplifyLibCalls.cpp b/lib/Transforms/Utils/SimplifyLibCalls.cpp
index 96f09d2..5d217bb 100644
--- a/lib/Transforms/Utils/SimplifyLibCalls.cpp
+++ b/lib/Transforms/Utils/SimplifyLibCalls.cpp
@@ -1502,6 +1502,81 @@
}
};
+struct FPrintFOpt : public LibCallOptimization {
+ Value *optimizeFixedFormatString(Function *Callee, CallInst *CI,
+ IRBuilder<> &B) {
+ // All the optimizations depend on the format string.
+ StringRef FormatStr;
+ if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
+ return 0;
+
+ // fprintf(F, "foo") --> fwrite("foo", 3, 1, F)
+ if (CI->getNumArgOperands() == 2) {
+ for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
+ if (FormatStr[i] == '%') // Could handle %% -> % if we cared.
+ return 0; // We found a format specifier.
+
+ // These optimizations require DataLayout.
+ if (!TD) return 0;
+
+ Value *NewCI = EmitFWrite(CI->getArgOperand(1),
+ ConstantInt::get(TD->getIntPtrType(*Context),
+ FormatStr.size()),
+ CI->getArgOperand(0), B, TD, TLI);
+ return NewCI ? ConstantInt::get(CI->getType(), FormatStr.size()) : 0;
+ }
+
+ // The remaining optimizations require the format string to be "%s" or "%c"
+ // and have an extra operand.
+ if (FormatStr.size() != 2 || FormatStr[0] != '%' ||
+ CI->getNumArgOperands() < 3)
+ return 0;
+
+ // Decode the second character of the format string.
+ if (FormatStr[1] == 'c') {
+ // fprintf(F, "%c", chr) --> fputc(chr, F)
+ if (!CI->getArgOperand(2)->getType()->isIntegerTy()) return 0;
+ Value *NewCI = EmitFPutC(CI->getArgOperand(2), CI->getArgOperand(0), B,
+ TD, TLI);
+ return NewCI ? ConstantInt::get(CI->getType(), 1) : 0;
+ }
+
+ if (FormatStr[1] == 's') {
+ // fprintf(F, "%s", str) --> fputs(str, F)
+ if (!CI->getArgOperand(2)->getType()->isPointerTy() || !CI->use_empty())
+ return 0;
+ return EmitFPutS(CI->getArgOperand(2), CI->getArgOperand(0), B, TD, TLI);
+ }
+ return 0;
+ }
+
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ // Require two fixed paramters as pointers and integer result.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
+ !FT->getParamType(1)->isPointerTy() ||
+ !FT->getReturnType()->isIntegerTy())
+ return 0;
+
+ if (Value *V = optimizeFixedFormatString(Callee, CI, B)) {
+ return V;
+ }
+
+ // fprintf(stream, format, ...) -> fiprintf(stream, format, ...) if no
+ // floating point arguments.
+ if (TLI->has(LibFunc::fiprintf) && !callHasFloatingPointArgument(CI)) {
+ Module *M = B.GetInsertBlock()->getParent()->getParent();
+ Constant *FIPrintFFn =
+ M->getOrInsertFunction("fiprintf", FT, Callee->getAttributes());
+ CallInst *New = cast<CallInst>(CI->clone());
+ New->setCalledFunction(FIPrintFFn);
+ B.Insert(New);
+ return New;
+ }
+ return 0;
+ }
+};
+
} // End anonymous namespace.
namespace llvm {
@@ -1558,6 +1633,7 @@
// Formatting and IO library call optimizations.
PrintFOpt PrintF;
SPrintFOpt SPrintF;
+ FPrintFOpt FPrintF;
void initOptimizations();
void addOpt(LibFunc::Func F, LibCallOptimization* Opt);
@@ -1683,6 +1759,7 @@
// Formatting and IO library call optimizations.
addOpt(LibFunc::printf, &PrintF);
addOpt(LibFunc::sprintf, &SPrintF);
+ addOpt(LibFunc::fprintf, &FPrintF);
}
Value *LibCallSimplifierImpl::optimizeCall(CallInst *CI) {