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; This test makes sure that these instructions are properly eliminated.
;
; RUN: llvm-as < %s | opt -instcombine -disable-output &&
; RUN: llvm-as < %s | opt -instcombine | llvm-dis | not grep sh
implementation
int %test1(int %A) {
%B = shl int %A, ubyte 0
ret int %B
}
int %test2(ubyte %A) {
%B = shl int 0, ubyte %A
ret int %B
}
int %test3(int %A) {
%B = shr int %A, ubyte 0
ret int %B
}
int %test4(ubyte %A) {
%B = shr int 0, ubyte %A
ret int %B
}
uint %test5(uint %A) {
%B = shr uint %A, ubyte 32 ;; shift all bits out
ret uint %B
}
uint %test5a(uint %A) {
%B = shl uint %A, ubyte 32 ;; shift all bits out
ret uint %B
}
uint %test6(uint %A) {
%B = shl uint %A, ubyte 1 ;; convert to an mul instruction
%C = mul uint %B, 3
ret uint %C
}
int %test7(ubyte %A) {
%B = shr int -1, ubyte %A ;; Always equal to -1
ret int %B
}
ubyte %test8(ubyte %A) { ;; (A << 5) << 3 === A << 8 == 0
%B = shl ubyte %A, ubyte 5
%C = shl ubyte %B, ubyte 3
ret ubyte %C
}
ubyte %test9(ubyte %A) { ;; (A << 7) >> 7 === A & 1
%B = shl ubyte %A, ubyte 7
%C = shr ubyte %B, ubyte 7
ret ubyte %C
}
ubyte %test10(ubyte %A) { ;; (A >> 7) << 7 === A & 128
%B = shr ubyte %A, ubyte 7
%C = shl ubyte %B, ubyte 7
ret ubyte %C
}
ubyte %test11(ubyte %A) { ;; (A >> 3) << 4 === (A & 0x1F) << 1
%a = mul ubyte %A, 3
%B = shr ubyte %a, ubyte 3
%C = shl ubyte %B, ubyte 4
ret ubyte %C
}
int %test12(int %A) {
%B = shr int %A, ubyte 8 ;; (A >> 8) << 8 === A & -256
%C = shl int %B, ubyte 8
ret int %C
}
sbyte %test13(sbyte %A) { ;; (A >> 3) << 4 === (A & -8) * 2
%a = mul sbyte %A, 3
%B = shr sbyte %a, ubyte 3
%C = shl sbyte %B, ubyte 4
ret sbyte %C
}
uint %test14(uint %A) {
%B = shr uint %A, ubyte 4
%C = or uint %B, 1234
%D = shl uint %C, ubyte 4 ;; D = ((B | 1234) << 4) === ((B << 4)|(1234 << 4)
ret uint %D
}
uint %test14a(uint %A) {
%B = shl uint %A, ubyte 4
%C = and uint %B, 1234
%D = shr uint %C, ubyte 4 ;; D = ((B | 1234) << 4) === ((B << 4)|(1234 << 4)
ret uint %D
}
int %test15(bool %C) {
%A = select bool %C, int 3, int 1
%V = shl int %A, ubyte 2
ret int %V
}
int %test15a(bool %C) {
%A = select bool %C, ubyte 3, ubyte 1
%V = shl int 64, ubyte %A
ret int %V
}
bool %test16(int %X) {
%tmp.3 = shr int %X, ubyte 4
%tmp.6 = and int %tmp.3, 1
%tmp.7 = setne int %tmp.6, 0 ;; X & 16 != 0
ret bool %tmp.7
}
bool %test17(uint %A) {
%B = shr uint %A, ubyte 3
%C = seteq uint %B, 1234
ret bool %C
}
bool %test18(ubyte %A) {
%B = shr ubyte %A, ubyte 7
%C = seteq ubyte %B, 123 ;; false
ret bool %C
}
bool %test19(int %A) {
%B = shr int %A, ubyte 2
%C = seteq int %B, 0 ;; (X & -4) == 0
ret bool %C
}
bool %test19a(int %A) {
%B = shr int %A, ubyte 2
%C = seteq int %B, -1 ;; (X & -4) == -4
ret bool %C
}
bool %test20(sbyte %A) {
%B = shr sbyte %A, ubyte 7
%C = seteq sbyte %B, 123 ;; false
ret bool %C
}
bool %test21(ubyte %A) {
%B = shl ubyte %A, ubyte 4
%C = seteq ubyte %B, 128
ret bool %C
}
bool %test22(ubyte %A) {
%B = shl ubyte %A, ubyte 4
%C = seteq ubyte %B, 0
ret bool %C
}
sbyte %test23(int %A) {
%B = shl int %A, ubyte 24 ;; casts not needed
%C = shr int %B, ubyte 24
%D = cast int %C to sbyte
ret sbyte %D
}
sbyte %test24(sbyte %X) {
%Y = and sbyte %X, -5 ; ~4
%Z = shl sbyte %Y, ubyte 5
%Q = shr sbyte %Z, ubyte 5
ret sbyte %Q
}
uint %test25(uint %tmp.2, uint %AA) {
%x = shr uint %AA, ubyte 17
%tmp.3 = shr uint %tmp.2, ubyte 17 ; <uint> [#uses=1]
%tmp.5 = add uint %tmp.3, %x ; <uint> [#uses=1]
%tmp.6 = shl uint %tmp.5, ubyte 17 ; <uint> [#uses=1]
ret uint %tmp.6
}
int %test26(uint %A) { ;; handle casts between shifts.
%B = shr uint %A, ubyte 1
%C = cast uint %B to int
%D = shl int %C, ubyte 1
ret int %D
}
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