[llvm-commits] [llvm] r144036 - in /llvm/trunk: lib/Transforms/InstCombine/InstCombineMulDivRem.cpp test/CodeGen/X86/vec_udiv_to_shift.ll

[Peter Cooper]

Thanks Eli.  Had no idea i needed that in ll files
On Nov 7, 2011, at 3:26 PM, Eli Friedman wrote:

> On Mon, Nov 7, 2011 at 3:04 PM, Pete Cooper <peter_cooper at apple.com> wrote:
>> Author: pete
>> Date: Mon Nov  7 17:04:49 2011
>> New Revision: 144036
>> 
>> URL: http://llvm.org/viewvc/llvm-project?rev=144036&view=rev
>> Log:
>> InstCombine now optimizes vector udiv by power of 2 to shifts
>> 
>> Fixes r8429
>> 
>> Added:
>>    llvm/trunk/test/CodeGen/X86/vec_udiv_to_shift.ll
>> Modified:
>>    llvm/trunk/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
>> 
>> Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp?rev=144036&r1=144035&r2=144036&view=diff
>> ==============================================================================
>> --- llvm/trunk/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp (original)
>> +++ llvm/trunk/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp Mon Nov  7 17:04:49 2011
>> @@ -441,19 +441,23 @@
>>   // Handle the integer div common cases
>>   if (Instruction *Common = commonIDivTransforms(I))
>>     return Common;
>> -
>> -  if (ConstantInt *C = dyn_cast<ConstantInt>(Op1)) {
>> +
>> +  {
>>     // X udiv 2^C -> X >> C
>>     // Check to see if this is an unsigned division with an exact power of 2,
>>     // if so, convert to a right shift.
>> -    if (C->getValue().isPowerOf2()) { // 0 not included in isPowerOf2
>> +    const APInt *C;
>> +    if (match(Op1, m_Power2(C))) {
>>       BinaryOperator *LShr =
>> -        BinaryOperator::CreateLShr(Op0,
>> -            ConstantInt::get(Op0->getType(), C->getValue().logBase2()));
>> +      BinaryOperator::CreateLShr(Op0,
>> +                                 ConstantInt::get(Op0->getType(),
>> +                                                  C->logBase2()));
>>       if (I.isExact()) LShr->setIsExact();
>>       return LShr;
>>     }
>> +  }
>> 
>> +  if (ConstantInt *C = dyn_cast<ConstantInt>(Op1)) {
>>     // X udiv C, where C >= signbit
>>     if (C->getValue().isNegative()) {
>>       Value *IC = Builder->CreateICmpULT(Op0, C);
>> 
>> Added: llvm/trunk/test/CodeGen/X86/vec_udiv_to_shift.ll
>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/vec_udiv_to_shift.ll?rev=144036&view=auto
>> ==============================================================================
>> --- llvm/trunk/test/CodeGen/X86/vec_udiv_to_shift.ll (added)
>> +++ llvm/trunk/test/CodeGen/X86/vec_udiv_to_shift.ll Mon Nov  7 17:04:49 2011
>> @@ -0,0 +1,15 @@
>> +; RUN: opt < %s -instcombine -S | FileCheck %s
>> +
>> +define <8 x i16> @udiv_vec8x16(<8 x i16> %var) {
>> +entry:
>> +; CHECK: lshr <8 x i16> %var, <i16 5, i16 5, i16 5, i16 5, i16 5, i16 5, i16 5, i16 5>
>> +%0 = udiv <8 x i16> %var, <i16 32, i16 32, i16 32, i16 32, i16 32, i16 32, i16 32, i16 32>
>> +ret <8 x i16> %0
>> +}
>> +
>> +define <4 x i32> @udiv_vec4x32(<4 x i32> %var) {
>> +entry:
>> +; CHECK: lshr <4 x i32> %var, <i32 4, i32 4, i32 4, i32 4>
>> +%0 = udiv <4 x i32> %var, <i32 16, i32 16, i32 16, i32 16>
>> +ret <4 x i32> %0
>> +}
>> \ No newline at end of file
> 
> ^ Newline?
> 
> -Eli