[llvm-branch-commits] [llvm-branch] r91231 - in /llvm/branches/Apple/Zoidberg/lib/Target/X86: X86InstrInfo.cpp X86InstrInfo.td

[Evan Cheng]

Author: evancheng
Date: Sat Dec 12 17:55:00 2009
New Revision: 91231

URL: http://llvm.org/viewvc/llvm-project?rev=91231&view=rev
Log:
Merge 91219 91220.

Modified:
    llvm/branches/Apple/Zoidberg/lib/Target/X86/X86InstrInfo.cpp
    llvm/branches/Apple/Zoidberg/lib/Target/X86/X86InstrInfo.td

Modified: llvm/branches/Apple/Zoidberg/lib/Target/X86/X86InstrInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/Apple/Zoidberg/lib/Target/X86/X86InstrInfo.cpp?rev=91231&r1=91230&r2=91231&view=diff

==============================================================================
--- llvm/branches/Apple/Zoidberg/lib/Target/X86/X86InstrInfo.cpp (original)
+++ llvm/branches/Apple/Zoidberg/lib/Target/X86/X86InstrInfo.cpp Sat Dec 12 17:55:00 2009
@@ -1075,6 +1075,11 @@
             
   // Build and insert into an implicit UNDEF value. This is OK because
   // well be shifting and then extracting the lower 16-bits. 
+  // This has the potential to cause partial stall. e.g.
+  //   movw    (%rbp,%rcx,2), %dx
+  //   leal    -65(%rdx), %esi
+  // But testing has shown this *does* help performance (at least on modern
+  // x86 machines).
   BuildMI(*MFI, MBBI, MI->getDebugLoc(), get(X86::IMPLICIT_DEF), leaInReg);
   MachineInstr *InsMI =
     BuildMI(*MFI, MBBI, MI->getDebugLoc(), get(X86::INSERT_SUBREG),leaInReg)

Modified: llvm/branches/Apple/Zoidberg/lib/Target/X86/X86InstrInfo.td
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/Apple/Zoidberg/lib/Target/X86/X86InstrInfo.td?rev=91231&r1=91230&r2=91231&view=diff

==============================================================================
--- llvm/branches/Apple/Zoidberg/lib/Target/X86/X86InstrInfo.td (original)
+++ llvm/branches/Apple/Zoidberg/lib/Target/X86/X86InstrInfo.td Sat Dec 12 17:55:00 2009
@@ -817,7 +817,7 @@
 
 let neverHasSideEffects = 1 in
 def LEA16r   : I<0x8D, MRMSrcMem,
-                 (outs GR16:$dst), (ins i32mem:$src),
+                 (outs GR16:$dst), (ins lea32mem:$src),
                  "lea{w}\t{$src|$dst}, {$dst|$src}", []>, OpSize;
 let isReMaterializable = 1 in
 def LEA32r   : I<0x8D, MRMSrcMem,