llvm-6502/test/Transforms/InstSimplify/AndOrXor.ll
Duncan Sands 4604fc7791 A shift of a power of two is a power of two or zero.
For completeness - not spotted in the wild.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143211 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-28 18:30:05 +00:00

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434 B
LLVM

; RUN: opt < %s -instsimplify -S | FileCheck %s
define i64 @pow2(i32 %x) {
; CHECK: @pow2
%negx = sub i32 0, %x
%x2 = and i32 %x, %negx
%e = zext i32 %x2 to i64
%nege = sub i64 0, %e
%e2 = and i64 %e, %nege
ret i64 %e2
; CHECK: ret i64 %e
}
define i64 @pow2b(i32 %x) {
; CHECK: @pow2b
%sh = shl i32 2, %x
%e = zext i32 %sh to i64
%nege = sub i64 0, %e
%e2 = and i64 %e, %nege
ret i64 %e2
; CHECK: ret i64 %e
}