[llvm] r276952 - [InstCombine] Handle failures from ConstantFoldConstantExpression

[Hans Wennborg via llvm-commits]

Ping?

On Thu, Jul 28, 2016 at 8:51 AM, Hans Wennborg <hwennborg at google.com> wrote:
> Something for 3.9?
>
> On Wed, Jul 27, 2016 at 7:29 PM, David Majnemer via llvm-commits
> <llvm-commits at lists.llvm.org> wrote:
>> Author: majnemer
>> Date: Wed Jul 27 21:29:06 2016
>> New Revision: 276952
>>
>> URL: http://llvm.org/viewvc/llvm-project?rev=276952&view=rev
>> Log:
>> [InstCombine] Handle failures from ConstantFoldConstantExpression
>>
>> ConstantFoldConstantExpression returns null when folding fails.
>>
>> This fixes PR28745.
>>
>> Modified:
>>     llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp
>>     llvm/trunk/test/Transforms/InstCombine/cast.ll
>>
>> Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp
>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp?rev=276952&r1=276951&r2=276952&view=diff
>> ==============================================================================
>> --- llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp (original)
>> +++ llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp Wed Jul 27 21:29:06 2016
>> @@ -162,7 +162,8 @@ Value *InstCombiner::EvaluateInDifferent
>>      C = ConstantExpr::getIntegerCast(C, Ty, isSigned /*Sext or ZExt*/);
>>      // If we got a constantexpr back, try to simplify it with DL info.
>>      if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C))
>> -      C = ConstantFoldConstantExpression(CE, DL, TLI);
>> +      if (Constant *FoldedC = ConstantFoldConstantExpression(CE, DL, TLI))
>> +        C = FoldedC;
>>      return C;
>>    }
>>
>>
>> Modified: llvm/trunk/test/Transforms/InstCombine/cast.ll
>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/cast.ll?rev=276952&r1=276951&r2=276952&view=diff
>> ==============================================================================
>> --- llvm/trunk/test/Transforms/InstCombine/cast.ll (original)
>> +++ llvm/trunk/test/Transforms/InstCombine/cast.ll Wed Jul 27 21:29:06 2016
>> @@ -1372,3 +1372,11 @@ define i16 @PR24763(i8 %V) {
>>    %t = trunc i32 %l to i16
>>    ret i16 %t
>>  }
>> +
>> +define i64 @PR28745() {
>> +; CHECK-LABEL: @PR28745(
>> +; CHECK-NEXT:    ret i64 zext (i32 extractvalue ({ i32 } select (i1 icmp eq (i16 extractelement (<2 x i16> bitcast (<1 x i32> <i32 1> to <2 x i16>), i32 0), i16 0), { i32 } { i32 1 }, { i32 } zeroinitializer), 0) to i64)
>> +
>> +  %b = zext i32 extractvalue ({ i32 } select (i1 icmp eq (i16 extractelement (<2 x i16> bitcast (<1 x i32> <i32 1> to <2 x i16>), i32 0), i16 0), { i32 } { i32 1 }, { i32 } zeroinitializer), 0) to i64
>> +  ret i64 %b
>> +}
>>
>>
>> _______________________________________________
>> llvm-commits mailing list
>> llvm-commits at lists.llvm.org
>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits