diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Transforms/Scalar/SimplifyLibCalls.cpp | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/lib/Transforms/Scalar/SimplifyLibCalls.cpp b/lib/Transforms/Scalar/SimplifyLibCalls.cpp index 075adc0187..f3184ecc86 100644 --- a/lib/Transforms/Scalar/SimplifyLibCalls.cpp +++ b/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); |