[llvm-commits] CVS: llvm/lib/Transforms/Scalar/InstructionCombining.cpp

[Reid Spencer]

Changes in directory llvm/lib/Transforms/Scalar:

InstructionCombining.cpp updated: 1.698 -> 1.699
---
Log message:

For PR1280: http://llvm.org/PR1280 :
When converting an add/xor/and triplet into a trunc/sext, only do so if the
intermediate integer type is a bitwidth that the targets can handle.


---
Diffs of the changes:  (+13 -3)

 InstructionCombining.cpp |   16 +++++++++++++---
 1 files changed, 13 insertions(+), 3 deletions(-)


Index: llvm/lib/Transforms/Scalar/InstructionCombining.cpp
diff -u llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.698 llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.699
--- llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.698	Tue Mar 27 11:44:48 2007
+++ llvm/lib/Transforms/Scalar/InstructionCombining.cpp	Tue Mar 27 20:36:16 2007
@@ -1940,11 +1940,21 @@
         CFF80Val = APIntOps::ashr(CFF80Val, Size);
       } while (Size >= 1);
       
-      if (Size) {
-        const Type *MiddleType = IntegerType::get(Size);
+      // FIXME: This shouldn't be necessary. When the backends can handle types
+      // with funny bit widths then this whole cascade of if statements should
+      // be removed. It is just here to get the size of the "middle" type back
+      // up to something that the back ends can handle.
+      const Type *MiddleType = 0;
+      switch (Size) {
+        default: break;
+        case 32: MiddleType = Type::Int32Ty; break;
+        case 16: MiddleType = Type::Int16Ty; break;
+        case  8: MiddleType = Type::Int8Ty; break;
+      }
+      if (MiddleType) {
         Instruction *NewTrunc = new TruncInst(XorLHS, MiddleType, "sext");
         InsertNewInstBefore(NewTrunc, I);
-        return new SExtInst(NewTrunc, I.getType());
+        return new SExtInst(NewTrunc, I.getType(), I.getName());
       }
     }
   }