Do not optimize (or (and X,Y), Z) into BFI and other sequences if the AND ISDNode has more than one user.

rdar://11876519



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161775 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Nadav Rotem 2012-08-13 18:52:44 +00:00
parent c586d26812
commit df8320313b
2 changed files with 22 additions and 1 deletions

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@ -7422,8 +7422,12 @@ static SDValue PerformORCombine(SDNode *N,
return COR;
}
// The code below optimizes (or (and X, Y), Z).
// The AND operand needs to have a single user to make these optimizations
// profitable.
SDValue N0 = N->getOperand(0);
if (N0.getOpcode() != ISD::AND)
if (N0.getOpcode() != ISD::AND || !N0.hasOneUse())
return SDValue();
SDValue N1 = N->getOperand(1);

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@ -0,0 +1,17 @@
; RUN: llc -march=thumb -mcpu=cortex-a8 < %s | FileCheck %s
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.8.0"
; CHECK: foo
; CHECK-NOT: bfi
; CHECK: bx
define i32 @foo(i8 zeroext %i) nounwind uwtable readnone ssp {
%1 = and i8 %i, 15
%2 = zext i8 %1 to i32
%3 = icmp ult i8 %1, 10
%4 = or i32 %2, 48
%5 = add nsw i32 %2, 55
%6 = select i1 %3, i32 %4, i32 %5
ret i32 %6
}