[llvm] r187635 - Teach InstructionSimplify about pointer address spaces

[Matt Arsenault]

On Aug 2, 2013, at 16:54 , Eli Friedman <eli.friedman at gmail.com> wrote:

> On Thu, Aug 1, 2013 at 5:10 PM, Matt Arsenault
> <Matthew.Arsenault at amd.com> wrote:
>> Author: arsenm
>> Date: Thu Aug  1 19:10:44 2013
>> New Revision: 187635
>> 
>> URL: http://llvm.org/viewvc/llvm-project?rev=187635&view=rev
>> Log:
>> Teach InstructionSimplify about pointer address spaces
>> 
>> Modified:
>>    llvm/trunk/lib/Analysis/InstructionSimplify.cpp
> 
> Testcase?

My tests for these require the other pieces up to InstCombine to be consistent, so the test will come with that change.

> 
>> Modified: llvm/trunk/lib/Analysis/InstructionSimplify.cpp
>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/InstructionSimplify.cpp?rev=187635&r1=187634&r2=187635&view=diff
>> ==============================================================================
>> --- llvm/trunk/lib/Analysis/InstructionSimplify.cpp (original)
>> +++ llvm/trunk/lib/Analysis/InstructionSimplify.cpp Thu Aug  1 19:10:44 2013
>> @@ -676,7 +676,8 @@ static Constant *stripAndComputeConstant
>>   if (!TD)
>>     return ConstantInt::get(IntegerType::get(V->getContext(), 64), 0);
>> 
>> -  unsigned IntPtrWidth = TD->getPointerSizeInBits();
>> +  unsigned AS = V->getType()->getPointerAddressSpace();
>> +  unsigned IntPtrWidth = TD->getPointerSizeInBits(AS);
>>   APInt Offset = APInt::getNullValue(IntPtrWidth);
>> 
>>   // Even though we don't look through PHI nodes, we could be called on an
>> @@ -689,7 +690,11 @@ static Constant *stripAndComputeConstant
>>         break;
>>       V = GEP->getPointerOperand();
>>     } else if (Operator::getOpcode(V) == Instruction::BitCast) {
>> -      V = cast<Operator>(V)->getOperand(0);
>> +      Value *Op0 = cast<Operator>(V)->getOperand(0);
>> +      assert(TD->getPointerTypeSizeInBits(V->getType()) ==
>> +             TD->getPointerTypeSizeInBits(Op0->getType()) &&
>> +             "Bitcasting between pointers from different size address spaces");
>> +      V = Op0;
> 
> 
> The verifier already checks this, no?
> 
Yes, but I did this before I did the verifier. It's not really needed anymore