llvm-project/llvm/test/CodeGen/X86/bitreverse.ll

; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s -mtriple=i686-unknown | FileCheck %s --check-prefix=X86
; RUN: llc < %s -mtriple=x86_64-unknown | FileCheck %s --check-prefix=X64

; These tests just check that the plumbing is in place for @llvm.bitreverse. The
; actual output is massive at the moment as llvm.bitreverse is not yet legal.

declare <2 x i16> @llvm.bitreverse.v2i16(<2 x i16>) readnone

define <2 x i16> @test_bitreverse_v2i16(<2 x i16> %a) nounwind {
; X86-LABEL: test_bitreverse_v2i16:
; X86:       # BB#0:
; X86-NEXT:    movw {{[0-9]+}}(%esp), %cx
; X86-NEXT:    movw {{[0-9]+}}(%esp), %ax
; X86-NEXT:    rolw $8, %ax
; X86-NEXT:    movl %eax, %edx
; X86-NEXT:    andl $3855, %edx # imm = 0xF0F
; X86-NEXT:    shll $4, %edx
; X86-NEXT:    andl $61680, %eax # imm = 0xF0F0
; X86-NEXT:    shrl $4, %eax
; X86-NEXT:    orl %edx, %eax
; X86-NEXT:    movl %eax, %edx
; X86-NEXT:    andl $13107, %edx # imm = 0x3333
; X86-NEXT:    andl $52428, %eax # imm = 0xCCCC
; X86-NEXT:    shrl $2, %eax
; X86-NEXT:    leal (%eax,%edx,4), %eax
; X86-NEXT:    movl %eax, %edx
; X86-NEXT:    andl $21845, %edx # imm = 0x5555
; X86-NEXT:    andl $43690, %eax # imm = 0xAAAA
; X86-NEXT:    shrl %eax
; X86-NEXT:    leal (%eax,%edx,2), %eax
; X86-NEXT:    rolw $8, %cx
; X86-NEXT:    movl %ecx, %edx
; X86-NEXT:    andl $3855, %edx # imm = 0xF0F
; X86-NEXT:    shll $4, %edx
; X86-NEXT:    andl $61680, %ecx # imm = 0xF0F0
; X86-NEXT:    shrl $4, %ecx
; X86-NEXT:    orl %edx, %ecx
; X86-NEXT:    movl %ecx, %edx
; X86-NEXT:    andl $13107, %edx # imm = 0x3333
; X86-NEXT:    andl $52428, %ecx # imm = 0xCCCC
; X86-NEXT:    shrl $2, %ecx
; X86-NEXT:    leal (%ecx,%edx,4), %ecx
; X86-NEXT:    movl %ecx, %edx
; X86-NEXT:    andl $21845, %edx # imm = 0x5555
; X86-NEXT:    andl $43690, %ecx # imm = 0xAAAA
; X86-NEXT:    shrl %ecx
; X86-NEXT:    leal (%ecx,%edx,2), %edx
; X86-NEXT:    # kill: %AX<def> %AX<kill> %EAX<kill>
; X86-NEXT:    # kill: %DX<def> %DX<kill> %EDX<kill>
; X86-NEXT:    retl
;
; X64-LABEL: test_bitreverse_v2i16:
; X64:       # BB#0:
; X64-NEXT:    pxor %xmm1, %xmm1
; X64-NEXT:    movdqa %xmm0, %xmm2
; X64-NEXT:    punpckhbw {{.*#+}} xmm2 = xmm2[8],xmm1[8],xmm2[9],xmm1[9],xmm2[10],xmm1[10],xmm2[11],xmm1[11],xmm2[12],xmm1[12],xmm2[13],xmm1[13],xmm2[14],xmm1[14],xmm2[15],xmm1[15]
; X64-NEXT:    pshufd {{.*#+}} xmm2 = xmm2[2,3,0,1]
; X64-NEXT:    pshuflw {{.*#+}} xmm2 = xmm2[3,2,1,0,4,5,6,7]
; X64-NEXT:    pshufhw {{.*#+}} xmm2 = xmm2[0,1,2,3,7,6,5,4]
; X64-NEXT:    punpcklbw {{.*#+}} xmm0 = xmm0[0],xmm1[0],xmm0[1],xmm1[1],xmm0[2],xmm1[2],xmm0[3],xmm1[3],xmm0[4],xmm1[4],xmm0[5],xmm1[5],xmm0[6],xmm1[6],xmm0[7],xmm1[7]
; X64-NEXT:    pshufd {{.*#+}} xmm0 = xmm0[2,3,0,1]
; X64-NEXT:    pshuflw {{.*#+}} xmm0 = xmm0[3,2,1,0,4,5,6,7]
; X64-NEXT:    pshufhw {{.*#+}} xmm0 = xmm0[0,1,2,3,7,6,5,4]
; X64-NEXT:    packuswb %xmm2, %xmm0
; X64-NEXT:    movdqa {{.*#+}} xmm1 = [15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15]
; X64-NEXT:    movdqa %xmm0, %xmm2
; X64-NEXT:    pand %xmm1, %xmm2
; X64-NEXT:    psllw $4, %xmm2
; X64-NEXT:    movdqa {{.*#+}} xmm3 = [240,240,240,240,240,240,240,240,240,240,240,240,240,240,240,240]
; X64-NEXT:    pand %xmm3, %xmm2
; X64-NEXT:    pand %xmm3, %xmm0
; X64-NEXT:    psrlw $4, %xmm0
; X64-NEXT:    pand %xmm1, %xmm0
; X64-NEXT:    por %xmm2, %xmm0
; X64-NEXT:    movdqa {{.*#+}} xmm1 = [51,51,51,51,51,51,51,51,51,51,51,51,51,51,51,51]
; X64-NEXT:    pand %xmm0, %xmm1
; X64-NEXT:    psllw $2, %xmm1
; X64-NEXT:    pand {{.*}}(%rip), %xmm1
; X64-NEXT:    pand {{.*}}(%rip), %xmm0
; X64-NEXT:    psrlw $2, %xmm0
; X64-NEXT:    pand {{.*}}(%rip), %xmm0
; X64-NEXT:    por %xmm1, %xmm0
; X64-NEXT:    movdqa {{.*#+}} xmm1 = [85,85,85,85,85,85,85,85,85,85,85,85,85,85,85,85]
; X64-NEXT:    pand %xmm0, %xmm1
; X64-NEXT:    paddb %xmm1, %xmm1
; X64-NEXT:    pand {{.*}}(%rip), %xmm0
; X64-NEXT:    psrlw $1, %xmm0
; X64-NEXT:    pand {{.*}}(%rip), %xmm0
; X64-NEXT:    por %xmm1, %xmm0
; X64-NEXT:    psrlq $48, %xmm0
; X64-NEXT:    retq
  %b = call <2 x i16> @llvm.bitreverse.v2i16(<2 x i16> %a)
  ret <2 x i16> %b
}

declare i64 @llvm.bitreverse.i64(i64) readnone

define i64 @test_bitreverse_i64(i64 %a) nounwind {
; X86-LABEL: test_bitreverse_i64:
; X86:       # BB#0:
; X86-NEXT:    movl {{[0-9]+}}(%esp), %ecx
; X86-NEXT:    movl {{[0-9]+}}(%esp), %eax
; X86-NEXT:    bswapl %eax
; X86-NEXT:    movl %eax, %edx
; X86-NEXT:    andl $252645135, %edx # imm = 0xF0F0F0F
; X86-NEXT:    shll $4, %edx
; X86-NEXT:    andl $-252645136, %eax # imm = 0xF0F0F0F0
; X86-NEXT:    shrl $4, %eax
; X86-NEXT:    orl %edx, %eax
; X86-NEXT:    movl %eax, %edx
; X86-NEXT:    andl $858993459, %edx # imm = 0x33333333
; X86-NEXT:    andl $-858993460, %eax # imm = 0xCCCCCCCC
; X86-NEXT:    shrl $2, %eax
; X86-NEXT:    leal (%eax,%edx,4), %eax
; X86-NEXT:    movl %eax, %edx
; X86-NEXT:    andl $1431655765, %edx # imm = 0x55555555
; X86-NEXT:    andl $-1431655766, %eax # imm = 0xAAAAAAAA
; X86-NEXT:    shrl %eax
; X86-NEXT:    leal (%eax,%edx,2), %eax
; X86-NEXT:    bswapl %ecx
; X86-NEXT:    movl %ecx, %edx
; X86-NEXT:    andl $252645135, %edx # imm = 0xF0F0F0F
; X86-NEXT:    shll $4, %edx
; X86-NEXT:    andl $-252645136, %ecx # imm = 0xF0F0F0F0
; X86-NEXT:    shrl $4, %ecx
; X86-NEXT:    orl %edx, %ecx
; X86-NEXT:    movl %ecx, %edx
; X86-NEXT:    andl $858993459, %edx # imm = 0x33333333
; X86-NEXT:    andl $-858993460, %ecx # imm = 0xCCCCCCCC
; X86-NEXT:    shrl $2, %ecx
; X86-NEXT:    leal (%ecx,%edx,4), %ecx
; X86-NEXT:    movl %ecx, %edx
; X86-NEXT:    andl $1431655765, %edx # imm = 0x55555555
; X86-NEXT:    andl $-1431655766, %ecx # imm = 0xAAAAAAAA
; X86-NEXT:    shrl %ecx
; X86-NEXT:    leal (%ecx,%edx,2), %edx
; X86-NEXT:    retl
;
; X64-LABEL: test_bitreverse_i64:
; X64:       # BB#0:
; X64-NEXT:    bswapq %rdi
; X64-NEXT:    movabsq $1085102592571150095, %rax # imm = 0xF0F0F0F0F0F0F0F
; X64-NEXT:    andq %rdi, %rax
; X64-NEXT:    shlq $4, %rax
; X64-NEXT:    movabsq $-1085102592571150096, %rcx # imm = 0xF0F0F0F0F0F0F0F0
; X64-NEXT:    andq %rdi, %rcx
; X64-NEXT:    shrq $4, %rcx
; X64-NEXT:    orq %rax, %rcx
; X64-NEXT:    movabsq $3689348814741910323, %rax # imm = 0x3333333333333333
; X64-NEXT:    andq %rcx, %rax
; X64-NEXT:    movabsq $-3689348814741910324, %rdx # imm = 0xCCCCCCCCCCCCCCCC
; X64-NEXT:    andq %rcx, %rdx
; X64-NEXT:    shrq $2, %rdx
; X64-NEXT:    leaq (%rdx,%rax,4), %rax
; X64-NEXT:    movabsq $6148914691236517205, %rcx # imm = 0x5555555555555555
; X64-NEXT:    andq %rax, %rcx
; X64-NEXT:    movabsq $-6148914691236517206, %rdx # imm = 0xAAAAAAAAAAAAAAAA
; X64-NEXT:    andq %rax, %rdx
; X64-NEXT:    shrq %rdx
; X64-NEXT:    leaq (%rdx,%rcx,2), %rax
; X64-NEXT:    retq
  %b = call i64 @llvm.bitreverse.i64(i64 %a)
  ret i64 %b
}

declare i32 @llvm.bitreverse.i32(i32) readnone

define i32 @test_bitreverse_i32(i32 %a) nounwind {
; X86-LABEL: test_bitreverse_i32:
; X86:       # BB#0:
; X86-NEXT:    movl {{[0-9]+}}(%esp), %eax
; X86-NEXT:    bswapl %eax
; X86-NEXT:    movl %eax, %ecx
; X86-NEXT:    andl $252645135, %ecx # imm = 0xF0F0F0F
; X86-NEXT:    shll $4, %ecx
; X86-NEXT:    andl $-252645136, %eax # imm = 0xF0F0F0F0
; X86-NEXT:    shrl $4, %eax
; X86-NEXT:    orl %ecx, %eax
; X86-NEXT:    movl %eax, %ecx
; X86-NEXT:    andl $858993459, %ecx # imm = 0x33333333
; X86-NEXT:    andl $-858993460, %eax # imm = 0xCCCCCCCC
; X86-NEXT:    shrl $2, %eax
; X86-NEXT:    leal (%eax,%ecx,4), %eax
; X86-NEXT:    movl %eax, %ecx
; X86-NEXT:    andl $1431655765, %ecx # imm = 0x55555555
; X86-NEXT:    andl $-1431655766, %eax # imm = 0xAAAAAAAA
; X86-NEXT:    shrl %eax
; X86-NEXT:    leal (%eax,%ecx,2), %eax
; X86-NEXT:    retl
;
; X64-LABEL: test_bitreverse_i32:
; X64:       # BB#0:
; X64-NEXT:    # kill: %EDI<def> %EDI<kill> %RDI<def>
; X64-NEXT:    bswapl %edi
; X64-NEXT:    movl %edi, %eax
; X64-NEXT:    andl $252645135, %eax # imm = 0xF0F0F0F
; X64-NEXT:    shll $4, %eax
; X64-NEXT:    andl $-252645136, %edi # imm = 0xF0F0F0F0
; X64-NEXT:    shrl $4, %edi
; X64-NEXT:    orl %eax, %edi
; X64-NEXT:    movl %edi, %eax
; X64-NEXT:    andl $858993459, %eax # imm = 0x33333333
; X64-NEXT:    andl $-858993460, %edi # imm = 0xCCCCCCCC
; X64-NEXT:    shrl $2, %edi
; X64-NEXT:    leal (%rdi,%rax,4), %eax
; X64-NEXT:    movl %eax, %ecx
; X64-NEXT:    andl $1431655765, %ecx # imm = 0x55555555
; X64-NEXT:    andl $-1431655766, %eax # imm = 0xAAAAAAAA
; X64-NEXT:    shrl %eax
; X64-NEXT:    leal (%rax,%rcx,2), %eax
; X64-NEXT:    retq
  %b = call i32 @llvm.bitreverse.i32(i32 %a)
  ret i32 %b
}

declare i24 @llvm.bitreverse.i24(i24) readnone

define i24 @test_bitreverse_i24(i24 %a) nounwind {
; X86-LABEL: test_bitreverse_i24:
; X86:       # BB#0:
; X86-NEXT:    movl {{[0-9]+}}(%esp), %eax
; X86-NEXT:    bswapl %eax
; X86-NEXT:    movl %eax, %ecx
; X86-NEXT:    andl $252645135, %ecx # imm = 0xF0F0F0F
; X86-NEXT:    shll $4, %ecx
; X86-NEXT:    andl $-252645136, %eax # imm = 0xF0F0F0F0
; X86-NEXT:    shrl $4, %eax
; X86-NEXT:    orl %ecx, %eax
; X86-NEXT:    movl %eax, %ecx
; X86-NEXT:    andl $858993459, %ecx # imm = 0x33333333
; X86-NEXT:    andl $-858993460, %eax # imm = 0xCCCCCCCC
; X86-NEXT:    shrl $2, %eax
; X86-NEXT:    leal (%eax,%ecx,4), %eax
; X86-NEXT:    movl %eax, %ecx
; X86-NEXT:    andl $1431655680, %ecx # imm = 0x55555500
; X86-NEXT:    andl $-1431655936, %eax # imm = 0xAAAAAA00
; X86-NEXT:    shrl %eax
; X86-NEXT:    leal (%eax,%ecx,2), %eax
; X86-NEXT:    shrl $8, %eax
; X86-NEXT:    retl
;
; X64-LABEL: test_bitreverse_i24:
; X64:       # BB#0:
; X64-NEXT:    # kill: %EDI<def> %EDI<kill> %RDI<def>
; X64-NEXT:    bswapl %edi
; X64-NEXT:    movl %edi, %eax
; X64-NEXT:    andl $252645135, %eax # imm = 0xF0F0F0F
; X64-NEXT:    shll $4, %eax
; X64-NEXT:    andl $-252645136, %edi # imm = 0xF0F0F0F0
; X64-NEXT:    shrl $4, %edi
; X64-NEXT:    orl %eax, %edi
; X64-NEXT:    movl %edi, %eax
; X64-NEXT:    andl $858993459, %eax # imm = 0x33333333
; X64-NEXT:    andl $-858993460, %edi # imm = 0xCCCCCCCC
; X64-NEXT:    shrl $2, %edi
; X64-NEXT:    leal (%rdi,%rax,4), %eax
; X64-NEXT:    movl %eax, %ecx
; X64-NEXT:    andl $1431655680, %ecx # imm = 0x55555500
; X64-NEXT:    andl $-1431655936, %eax # imm = 0xAAAAAA00
; X64-NEXT:    shrl %eax
; X64-NEXT:    leal (%rax,%rcx,2), %eax
; X64-NEXT:    shrl $8, %eax
; X64-NEXT:    retq
  %b = call i24 @llvm.bitreverse.i24(i24 %a)
  ret i24 %b
}

declare i16 @llvm.bitreverse.i16(i16) readnone

define i16 @test_bitreverse_i16(i16 %a) nounwind {
; X86-LABEL: test_bitreverse_i16:
; X86:       # BB#0:
; X86-NEXT:    movw {{[0-9]+}}(%esp), %ax
; X86-NEXT:    rolw $8, %ax
; X86-NEXT:    movl %eax, %ecx
; X86-NEXT:    andl $3855, %ecx # imm = 0xF0F
; X86-NEXT:    shll $4, %ecx
; X86-NEXT:    andl $61680, %eax # imm = 0xF0F0
; X86-NEXT:    shrl $4, %eax
; X86-NEXT:    orl %ecx, %eax
; X86-NEXT:    movl %eax, %ecx
; X86-NEXT:    andl $13107, %ecx # imm = 0x3333
; X86-NEXT:    andl $52428, %eax # imm = 0xCCCC
; X86-NEXT:    shrl $2, %eax
; X86-NEXT:    leal (%eax,%ecx,4), %eax
; X86-NEXT:    movl %eax, %ecx
; X86-NEXT:    andl $21845, %ecx # imm = 0x5555
; X86-NEXT:    andl $43690, %eax # imm = 0xAAAA
; X86-NEXT:    shrl %eax
; X86-NEXT:    leal (%eax,%ecx,2), %eax
; X86-NEXT:    # kill: %AX<def> %AX<kill> %EAX<kill>
; X86-NEXT:    retl
;
; X64-LABEL: test_bitreverse_i16:
; X64:       # BB#0:
; X64-NEXT:    # kill: %EDI<def> %EDI<kill> %RDI<def>
; X64-NEXT:    rolw $8, %di
; X64-NEXT:    movl %edi, %eax
; X64-NEXT:    andl $3855, %eax # imm = 0xF0F
; X64-NEXT:    shll $4, %eax
; X64-NEXT:    andl $61680, %edi # imm = 0xF0F0
; X64-NEXT:    shrl $4, %edi
; X64-NEXT:    orl %eax, %edi
; X64-NEXT:    movl %edi, %eax
; X64-NEXT:    andl $13107, %eax # imm = 0x3333
; X64-NEXT:    andl $52428, %edi # imm = 0xCCCC
; X64-NEXT:    shrl $2, %edi
; X64-NEXT:    leal (%rdi,%rax,4), %eax
; X64-NEXT:    movl %eax, %ecx
; X64-NEXT:    andl $21845, %ecx # imm = 0x5555
; X64-NEXT:    andl $43690, %eax # imm = 0xAAAA
; X64-NEXT:    shrl %eax
; X64-NEXT:    leal (%rax,%rcx,2), %eax
; X64-NEXT:    # kill: %AX<def> %AX<kill> %EAX<kill>
; X64-NEXT:    retq
  %b = call i16 @llvm.bitreverse.i16(i16 %a)
  ret i16 %b
}

declare i8 @llvm.bitreverse.i8(i8) readnone

define i8 @test_bitreverse_i8(i8 %a) {
; X86-LABEL: test_bitreverse_i8:
; X86:       # BB#0:
; X86-NEXT:    movb {{[0-9]+}}(%esp), %al
; X86-NEXT:    rolb $4, %al
; X86-NEXT:    movl %eax, %ecx
; X86-NEXT:    andb $51, %cl
; X86-NEXT:    shlb $2, %cl
; X86-NEXT:    andb $-52, %al
; X86-NEXT:    shrb $2, %al
; X86-NEXT:    orb %cl, %al
; X86-NEXT:    movl %eax, %ecx
; X86-NEXT:    andb $85, %cl
; X86-NEXT:    addb %cl, %cl
; X86-NEXT:    andb $-86, %al
; X86-NEXT:    shrb %al
; X86-NEXT:    orb %cl, %al
; X86-NEXT:    retl
;
; X64-LABEL: test_bitreverse_i8:
; X64:       # BB#0:
; X64-NEXT:    rolb $4, %dil
; X64-NEXT:    movl %edi, %eax
; X64-NEXT:    andb $51, %al
; X64-NEXT:    shlb $2, %al
; X64-NEXT:    andb $-52, %dil
; X64-NEXT:    shrb $2, %dil
; X64-NEXT:    orb %al, %dil
; X64-NEXT:    movl %edi, %eax
; X64-NEXT:    andb $85, %al
; X64-NEXT:    addb %al, %al
; X64-NEXT:    andb $-86, %dil
; X64-NEXT:    shrb %dil
; X64-NEXT:    orb %al, %dil
; X64-NEXT:    movl %edi, %eax
; X64-NEXT:    retq
  %b = call i8 @llvm.bitreverse.i8(i8 %a)
  ret i8 %b
}

declare i4 @llvm.bitreverse.i4(i4) readnone

define i4 @test_bitreverse_i4(i4 %a) {
; X86-LABEL: test_bitreverse_i4:
; X86:       # BB#0:
; X86-NEXT:    movb {{[0-9]+}}(%esp), %al
; X86-NEXT:    rolb $4, %al
; X86-NEXT:    movl %eax, %ecx
; X86-NEXT:    andb $51, %cl
; X86-NEXT:    shlb $2, %cl
; X86-NEXT:    andb $-52, %al
; X86-NEXT:    shrb $2, %al
; X86-NEXT:    orb %cl, %al
; X86-NEXT:    movl %eax, %ecx
; X86-NEXT:    andb $80, %cl
; X86-NEXT:    addb %cl, %cl
; X86-NEXT:    andb $-96, %al
; X86-NEXT:    shrb %al
; X86-NEXT:    orb %cl, %al
; X86-NEXT:    shrb $4, %al
; X86-NEXT:    retl
;
; X64-LABEL: test_bitreverse_i4:
; X64:       # BB#0:
; X64-NEXT:    rolb $4, %dil
; X64-NEXT:    movl %edi, %eax
; X64-NEXT:    andb $51, %al
; X64-NEXT:    shlb $2, %al
; X64-NEXT:    andb $-52, %dil
; X64-NEXT:    shrb $2, %dil
; X64-NEXT:    orb %al, %dil
; X64-NEXT:    movl %edi, %eax
; X64-NEXT:    andb $80, %al
; X64-NEXT:    addb %al, %al
; X64-NEXT:    andb $-96, %dil
; X64-NEXT:    shrb %dil
; X64-NEXT:    orb %al, %dil
; X64-NEXT:    shrb $4, %dil
; X64-NEXT:    movl %edi, %eax
; X64-NEXT:    retq
  %b = call i4 @llvm.bitreverse.i4(i4 %a)
  ret i4 %b
}

; These tests check that bitreverse(constant) calls are folded

define <2 x i16> @fold_v2i16() {
; X86-LABEL: fold_v2i16:
; X86:       # BB#0:
; X86-NEXT:    movw $-4096, %ax # imm = 0xF000
; X86-NEXT:    movw $240, %dx
; X86-NEXT:    retl
;
; X64-LABEL: fold_v2i16:
; X64:       # BB#0:
; X64-NEXT:    movaps {{.*#+}} xmm0 = [61440,240]
; X64-NEXT:    retq
  %b = call <2 x i16> @llvm.bitreverse.v2i16(<2 x i16> <i16 15, i16 3840>)
  ret <2 x i16> %b
}

define i24 @fold_i24() {
; X86-LABEL: fold_i24:
; X86:       # BB#0:
; X86-NEXT:    movl $2048, %eax # imm = 0x800
; X86-NEXT:    retl
;
; X64-LABEL: fold_i24:
; X64:       # BB#0:
; X64-NEXT:    movl $2048, %eax # imm = 0x800
; X64-NEXT:    retq
  %b = call i24 @llvm.bitreverse.i24(i24 4096)
  ret i24 %b
}

define i8 @fold_i8() {
; X86-LABEL: fold_i8:
; X86:       # BB#0:
; X86-NEXT:    movb $-16, %al
; X86-NEXT:    retl
;
; X64-LABEL: fold_i8:
; X64:       # BB#0:
; X64-NEXT:    movb $-16, %al
; X64-NEXT:    retq
  %b = call i8 @llvm.bitreverse.i8(i8 15)
  ret i8 %b
}

define i4 @fold_i4() {
; X86-LABEL: fold_i4:
; X86:       # BB#0:
; X86-NEXT:    movb $1, %al
; X86-NEXT:    retl
;
; X64-LABEL: fold_i4:
; X64:       # BB#0:
; X64-NEXT:    movb $1, %al
; X64-NEXT:    retq
  %b = call i4 @llvm.bitreverse.i4(i4 8)
  ret i4 %b
}

; These tests check that bitreverse(bitreverse()) calls are removed

define i8 @identity_i8(i8 %a) {
; X86-LABEL: identity_i8:
; X86:       # BB#0:
; X86-NEXT:    movb {{[0-9]+}}(%esp), %al
; X86-NEXT:    retl
;
; X64-LABEL: identity_i8:
; X64:       # BB#0:
; X64-NEXT:    movl %edi, %eax
; X64-NEXT:    retq
  %b = call i8 @llvm.bitreverse.i8(i8 %a)
  %c = call i8 @llvm.bitreverse.i8(i8 %b)
  ret i8 %c
}

define <2 x i16> @identity_v2i16(<2 x i16> %a) {
; X86-LABEL: identity_v2i16:
; X86:       # BB#0:
; X86-NEXT:    movzwl {{[0-9]+}}(%esp), %eax
; X86-NEXT:    movzwl {{[0-9]+}}(%esp), %edx
; X86-NEXT:    retl
;
; X64-LABEL: identity_v2i16:
; X64:       # BB#0:
; X64-NEXT:    retq
  %b = call <2 x i16> @llvm.bitreverse.v2i16(<2 x i16> %a)
  %c = call <2 x i16> @llvm.bitreverse.v2i16(<2 x i16> %b)
  ret <2 x i16> %c
}

; These tests check that bitreverse(undef) calls are removed

define i8 @undef_i8() {
; X86-LABEL: undef_i8:
; X86:       # BB#0:
; X86-NEXT:    retl
;
; X64-LABEL: undef_i8:
; X64:       # BB#0:
; X64-NEXT:    retq
  %b = call i8 @llvm.bitreverse.i8(i8 undef)
  ret i8 %b
}

define <2 x i16> @undef_v2i16() {
; X86-LABEL: undef_v2i16:
; X86:       # BB#0:
; X86-NEXT:    retl
;
; X64-LABEL: undef_v2i16:
; X64:       # BB#0:
; X64-NEXT:    retq
  %b = call <2 x i16> @llvm.bitreverse.v2i16(<2 x i16> undef)
  ret <2 x i16> %b
}