From 45c41641664d8ff44c03f6205312d347081882b0 Mon Sep 17 00:00:00 2001 From: Joerg Sonnenberger Date: Mon, 12 Dec 2011 20:18:31 +0000 Subject: Only replace fwrite with fputc, if the return value is unused. llvm-svn: 146411 --- llvm/lib/Transforms/Scalar/SimplifyLibCalls.cpp | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'llvm/lib/Transforms') diff --git a/llvm/lib/Transforms/Scalar/SimplifyLibCalls.cpp b/llvm/lib/Transforms/Scalar/SimplifyLibCalls.cpp index 075adc01873..f3184ecc860 100644 --- a/llvm/lib/Transforms/Scalar/SimplifyLibCalls.cpp +++ b/llvm/lib/Transforms/Scalar/SimplifyLibCalls.cpp @@ -1293,7 +1293,8 @@ struct FWriteOpt : public LibCallOptimization { return ConstantInt::get(CI->getType(), 0); // If this is writing one byte, turn it into fputc. - if (Bytes == 1) { // fwrite(S,1,1,F) -> fputc(S[0],F) + // This optimisation is only valid, if the return value is unused. + if (Bytes == 1 && CI->use_empty()) { // fwrite(S,1,1,F) -> fputc(S[0],F) Value *Char = B.CreateLoad(CastToCStr(CI->getArgOperand(0), B), "char"); EmitFPutC(Char, CI->getArgOperand(3), B, TD); return ConstantInt::get(CI->getType(), 1); -- cgit v1.2.3