Disable 2->3 address promotion of add and inc instructions to LEA's. In
addition to being three address, LEA's don't set the flags.
This fixes 186.crafty.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@19251 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86InstrInfo.cpp b/lib/Target/X86/X86InstrInfo.cpp
index d588afe..a13498e 100644
--- a/lib/Target/X86/X86InstrInfo.cpp
+++ b/lib/Target/X86/X86InstrInfo.cpp
@@ -55,6 +55,11 @@
unsigned Dest = MI->getOperand(0).getReg();
unsigned Src = MI->getOperand(1).getReg();
+ // FIXME: None of these instructions are promotable to LEAs without
+ // additional information. In particular, LEA doesn't set the flags that
+ // add and inc do. :(
+ return 0;
+
// FIXME: 16-bit LEA's are really slow on Athlons, but not bad on P4's. When
// we have subtarget support, enable the 16-bit LEA generation here.
bool DisableLEA16 = true;