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; This test makes sure that these instructions are properly eliminated.
;
; RUN: llvm-as < %s | opt -instcombine | llvm-dis | not grep and
implementation
int %test1(int %A) {
%B = and int %A, 0 ; zero result
ret int %B
}
int %test2(int %A) {
%B = and int %A, -1 ; noop
ret int %B
}
bool %test3(bool %A) {
%B = and bool %A, false ; always = false
ret bool %B
}
bool %test4(bool %A) {
%B = and bool %A, true ; noop
ret bool %B
}
int %test5(int %A) {
%B = and int %A, %A
ret int %B
}
bool %test6(bool %A) {
%B = and bool %A, %A
ret bool %B
}
int %test7(int %A) { ; A & ~A == 0
%NotA = xor int %A, -1
%B = and int %A, %NotA
ret int %B
}
ubyte %test8(ubyte %A) { ; AND associates
%B = and ubyte %A, 3
%C = and ubyte %B, 4
ret ubyte %C
}
bool %test9(int %A) {
%B = and int %A, -2147483648 ; Test of sign bit, convert to setle %A, 0
%C = setne int %B, 0
ret bool %C
}
bool %test9(uint %A) {
%B = and uint %A, 2147483648 ; Test of sign bit, convert to setle %A, 0
%C = setne uint %B, 0
ret bool %C
}
uint %test10(uint %A) {
%B = and uint %A, 12
%C = xor uint %B, 15
%D = and uint %C, 1 ; (X ^ C1) & C2 --> (X & C2) ^ (C1&C2)
ret uint %D
}
uint %test11(uint %A, uint* %P) {
%B = or uint %A, 3
%C = xor uint %B, 12
store uint %C, uint* %P ; additional use of C
%D = and uint %C, 3 ; %C = and uint %B, 3 --> 3
ret uint %D
}
bool %test12(uint %A, uint %B) {
%C1 = setlt uint %A, %B
%C2 = setle uint %A, %B
%D = and bool %C1, %C2 ; (A < B) & (A <= B) === (A < B)
ret bool %D
}
bool %test13(uint %A, uint %B) {
%C1 = setlt uint %A, %B
%C2 = setgt uint %A, %B
%D = and bool %C1, %C2 ; (A < B) & (A > B) === false
ret bool %D
}
bool %test14(ubyte %A) {
%B = and ubyte %A, 128
%C = setne ubyte %B, 0
ret bool %C
}
ubyte %test15(ubyte %A) {
%B = shr ubyte %A, ubyte 7
%C = and ubyte %B, 2 ; Always equals zero
ret ubyte %C
}
ubyte %test16(ubyte %A) {
%B = shl ubyte %A, ubyte 2
%C = and ubyte %B, 3
ret ubyte %C
}
sbyte %test17(sbyte %X, sbyte %Y) { ;; ~(~X & Y) --> (X | ~Y)
%B = xor sbyte %X, -1
%C = and sbyte %B, %Y
%D = xor sbyte %C, -1
ret sbyte %D
}
bool %test18(int %A) {
%B = and int %A, -128
%C = setne int %B, 0 ;; C >= 128
ret bool %C
}
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