From: Arnold Schwaighofer <aschwaighofer@apple.com>
Date: Wed, 5 Jun 2013 14:59:36 +0000 (+0000)
Subject: ARMInstrInfo: Improve isSwiftFastImmShift
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=d87bd5627e5b78cb556d6c7b5aa76ae3d55d8acf;p=oota-llvm.git

ARMInstrInfo: Improve isSwiftFastImmShift

An instruction with less than 3 inputs is trivially a fast immediate shift.

Reapply of 183256, should not have caused the tablegen segfault on linux either.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183314 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/ARM/ARMBaseInstrInfo.cpp b/lib/Target/ARM/ARMBaseInstrInfo.cpp
index 60050542716..b530515cdd8 100644
--- a/lib/Target/ARM/ARMBaseInstrInfo.cpp
+++ b/lib/Target/ARM/ARMBaseInstrInfo.cpp
@@ -4152,6 +4152,8 @@ bool ARMBaseInstrInfo::hasNOP() const {
 }
 
 bool ARMBaseInstrInfo::isSwiftFastImmShift(const MachineInstr *MI) const {
+  if (MI->getNumOperands() < 4)
+    return true;
   unsigned ShOpVal = MI->getOperand(3).getImm();
   unsigned ShImm = ARM_AM::getSORegOffset(ShOpVal);
   // Swift supports faster shifts for: lsl 2, lsl 1, and lsr 1.