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| ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s -mtriple=i686-unknown-unknown | FileCheck %s
; RUN: llc < %s -mtriple=x86_64-unknown-unknown | FileCheck %s --check-prefix=CHECK64
; Check reconstructing bswap from shifted masks and tree of ORs
; Match a 32-bit packed halfword bswap. That is
; ((x & 0x000000ff) << 8) |
; ((x & 0x0000ff00) >> 8) |
; ((x & 0x00ff0000) << 8) |
; ((x & 0xff000000) >> 8)
; => (rotl (bswap x), 16)
define i32 @test1(i32 %x) nounwind {
; CHECK-LABEL: test1:
; CHECK: # %bb.0:
; CHECK-NEXT: movl {{[0-9]+}}(%esp), %eax
; CHECK-NEXT: bswapl %eax
; CHECK-NEXT: roll $16, %eax
; CHECK-NEXT: retl
;
; CHECK64-LABEL: test1:
; CHECK64: # %bb.0:
; CHECK64-NEXT: movl %edi, %eax
; CHECK64-NEXT: bswapl %eax
; CHECK64-NEXT: roll $16, %eax
; CHECK64-NEXT: retq
%byte0 = and i32 %x, 255 ; 0x000000ff
%byte1 = and i32 %x, 65280 ; 0x0000ff00
%byte2 = and i32 %x, 16711680 ; 0x00ff0000
%byte3 = and i32 %x, 4278190080 ; 0xff000000
%tmp0 = shl i32 %byte0, 8
%tmp1 = lshr i32 %byte1, 8
%tmp2 = shl i32 %byte2, 8
%tmp3 = lshr i32 %byte3, 8
%or0 = or i32 %tmp0, %tmp1
%or1 = or i32 %tmp2, %tmp3
%result = or i32 %or0, %or1
ret i32 %result
}
; the same as test1, just shifts before the "and"
; ((x << 8) & 0x0000ff00) |
; ((x >> 8) & 0x000000ff) |
; ((x << 8) & 0xff000000) |
; ((x >> 8) & 0x00ff0000)
define i32 @test2(i32 %x) nounwind {
; CHECK-LABEL: test2:
; CHECK: # %bb.0:
; CHECK-NEXT: movl {{[0-9]+}}(%esp), %eax
; CHECK-NEXT: bswapl %eax
; CHECK-NEXT: roll $16, %eax
; CHECK-NEXT: retl
;
; CHECK64-LABEL: test2:
; CHECK64: # %bb.0:
; CHECK64-NEXT: movl %edi, %eax
; CHECK64-NEXT: bswapl %eax
; CHECK64-NEXT: roll $16, %eax
; CHECK64-NEXT: retq
%byte1 = shl i32 %x, 8
%byte0 = lshr i32 %x, 8
%byte3 = shl i32 %x, 8
%byte2 = lshr i32 %x, 8
%tmp1 = and i32 %byte1, 65280 ; 0x0000ff00
%tmp0 = and i32 %byte0, 255 ; 0x000000ff
%tmp3 = and i32 %byte3, 4278190080 ; 0xff000000
%tmp2 = and i32 %byte2, 16711680 ; 0x00ff0000
%or0 = or i32 %tmp0, %tmp1
%or1 = or i32 %tmp2, %tmp3
%result = or i32 %or0, %or1
ret i32 %result
}
declare i32 @llvm.bswap.i32(i32)
; Match a 32-bit packed halfword bswap, with some subtree
; already converted to a bswap.
define i32 @test3(i32 %x) nounwind {
; CHECK-LABEL: test3:
; CHECK: # %bb.0:
; CHECK-NEXT: movl {{[0-9]+}}(%esp), %eax
; CHECK-NEXT: bswapl %eax
; CHECK-NEXT: roll $16, %eax
; CHECK-NEXT: retl
;
; CHECK64-LABEL: test3:
; CHECK64: # %bb.0:
; CHECK64-NEXT: movl %edi, %eax
; CHECK64-NEXT: bswapl %eax
; CHECK64-NEXT: roll $16, %eax
; CHECK64-NEXT: retq
%byte2 = and i32 %x, 16711680 ; 0x00ff0000
%byte3 = and i32 %x, 4278190080 ; 0xff000000
%1 = shl i32 %byte2, 8
%2 = lshr i32 %byte3, 8
%or = or i32 %1, %2
%bswap = call i32 @llvm.bswap.i32(i32 %x)
%3 = lshr i32 %bswap, 16
%result = or i32 %or, %3
ret i32 %result
}
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