search for: instcombinecompar

In InstCombineCompares.cpp, routine InstCombiner::FoldFCmp_IntToFP_Cst, there are these lines: // Comparisons with zero are a special case where we know we won't lose // information. bool IsCmpZero = RHS.isPosZero(); // If the conversion would lose info, don't hack on this. if ((int)InputSize > M...

...mean to remove the hack in InstCombiner::visitICmpInst()? > > > > Yes. Although (this just came up in D28625 too) we might need to remove multiple versions of that in order to unlock optimization: > > https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstCombineCompares.cpp#L4338 <https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstCombineCompares.cpp#L4338> > https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstCombineCasts.cpp#L470 <https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/I...

...rtex-A15 LNT machines > Do you mean to remove the hack in InstCombiner::visitICmpInst()? Yes. Although (this just came up in D28625 too) we might need to remove multiple versions of that in order to unlock optimization: https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstCombineCompares.cpp#L4338 https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstCombineCasts.cpp#L470 https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstructionCombining.cpp#L803 https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstCo...

...rtex-A15 LNT machines > Do you mean to remove the hack in InstCombiner::visitICmpInst()? Yes. Although (this just came up in D28625 too) we might need to remove multiple versions of that in order to unlock optimization: https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstCombineCompares.cpp#L4338 https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstCombineCasts.cpp#L470 https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstructionCombining.cpp#L803 https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstCo...

...in InstCombiner::visitICmpInst()? >> >> >> >> Yes. Although (this just came up in D28625 too) we might need to remove multiple versions of that in order to unlock optimization: >> >> https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstCombineCompares.cpp#L4338 <https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstCombineCompares.cpp#L4338> >> https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstCombineCasts.cpp#L470 <https://github.com/llvm-mirror/llvm/blob/master/lib/Transfor...

Hi, I’m looking at what the LLVM compilation chain does to optimize the following functions using logical operators. The one using integer type (t1 and t3) are optimized, but not the ones using float type (t2 and t4), even when using -O3 or -Ofast. Why is that ? Thera are those kind of optimizations done in the LLVM source code? Thanks. bool t1(int v1) { return (2 + v1) == 7; } bool

Hi Sanjay, The benchmark source file: http://www.llvm.org/viewvc/llvm-project/test-suite/trunk/SingleSource/Benchmarks/Shootout/sieve.c?view=markup Clang options used to produce the initial IR: clang -DNDEBUG -O3 -DNDEBUG -mcpu=cortex-a53 -fomit-frame-pointer -O3 -DNDEBUG -w -Werror=date-time -c sieve.c -S -emit-llvm -mllvm -disable-llvm-optzns --target=aarch64-arm-linux Opt options: opt -O3

Hi, Working on private backend, based on llvm-3.7 Inside lib/Transforms/InstCombine/InstCombineCompares.cpp there is attempt to optimize fabs: if (F->getIntrinsicID() == Intrinsic::fabs || ... switch (I.getPredicate()) { ... case FCmpInst::FCMP_OGT: return new FCmpInst(FCmpInst::FCMP_ONE, CI->getArgOperand(0), RHSC); But CI->getArgOperand(0) retur...

...rtex-A15 LNT machines > Do you mean to remove the hack in InstCombiner::visitICmpInst()? Yes. Although (this just came up in D28625 too) we might need to remove multiple versions of that in order to unlock optimization: https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstCombineCompares.cpp#L4338 https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstCombineCasts.cpp#L470 https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstructionCombining.cpp#L803 https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstCo...

Hello, What follows is my attempt to describe how poison works. Let me know what you think. -- David # LLVM Poison Semantics Poison is an LLVM concept which exists solely to enable further optimization of LLVM IR. The exact behavior of poison has been, to say the least, confusing for users, researchers and engineers working with LLVM. This document hopes to clear up some of the confusion

...Asserts build llvm[3]: Compiling DwarfDebug.cpp for Release+Asserts build llvm[3]: Compiling X86TargetObjectFile.cpp for Release+Asserts build llvm[3]: Compiling InstCombineCasts.cpp for Release+Asserts build llvm[3]: Compiling X86TargetTransformInfo.cpp for Release+Asserts build llvm[3]: Compiling InstCombineCompares.cpp for Release+Asserts build llvm[3]: Compiling LoopUnrollPass.cpp for Release+Asserts build llvm[3]: Compiling X86VZeroUpper.cpp for Release+Asserts build llvm[3]: Compiling DwarfExpression.cpp for Release+Asserts build llvm[3]: Compiling LoopUnswitch.cpp for Release+Asserts build llvm[3]: Comp...