llvm/test/Transforms/InstCombine/and.ll
David Majnemer 377a5c1a87 InstCombine: add more transforms
C1-X <u C2 -> (X|(C2-1)) == C1
C1-X >u C2 -> (X|C2) == C1
X-C1 <u C2 -> (X & -C2) == C1
X-C1 >u C2 -> (X & ~C2) == C1


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185909 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-09 07:50:59 +00:00

256 lines
7.3 KiB
LLVM

; This test makes sure that these instructions are properly eliminated.
;
; RUN: opt < %s -instcombine -S | not grep and
define i32 @test1(i32 %A) {
; zero result
%B = and i32 %A, 0 ; <i32> [#uses=1]
ret i32 %B
}
define i32 @test2(i32 %A) {
; noop
%B = and i32 %A, -1 ; <i32> [#uses=1]
ret i32 %B
}
define i1 @test3(i1 %A) {
; always = false
%B = and i1 %A, false ; <i1> [#uses=1]
ret i1 %B
}
define i1 @test4(i1 %A) {
; noop
%B = and i1 %A, true ; <i1> [#uses=1]
ret i1 %B
}
define i32 @test5(i32 %A) {
%B = and i32 %A, %A ; <i32> [#uses=1]
ret i32 %B
}
define i1 @test6(i1 %A) {
%B = and i1 %A, %A ; <i1> [#uses=1]
ret i1 %B
}
; A & ~A == 0
define i32 @test7(i32 %A) {
%NotA = xor i32 %A, -1 ; <i32> [#uses=1]
%B = and i32 %A, %NotA ; <i32> [#uses=1]
ret i32 %B
}
; AND associates
define i8 @test8(i8 %A) {
%B = and i8 %A, 3 ; <i8> [#uses=1]
%C = and i8 %B, 4 ; <i8> [#uses=1]
ret i8 %C
}
define i1 @test9(i32 %A) {
; Test of sign bit, convert to setle %A, 0
%B = and i32 %A, -2147483648 ; <i32> [#uses=1]
%C = icmp ne i32 %B, 0 ; <i1> [#uses=1]
ret i1 %C
}
define i1 @test9a(i32 %A) {
; Test of sign bit, convert to setle %A, 0
%B = and i32 %A, -2147483648 ; <i32> [#uses=1]
%C = icmp ne i32 %B, 0 ; <i1> [#uses=1]
ret i1 %C
}
define i32 @test10(i32 %A) {
%B = and i32 %A, 12 ; <i32> [#uses=1]
%C = xor i32 %B, 15 ; <i32> [#uses=1]
; (X ^ C1) & C2 --> (X & C2) ^ (C1&C2)
%D = and i32 %C, 1 ; <i32> [#uses=1]
ret i32 %D
}
define i32 @test11(i32 %A, i32* %P) {
%B = or i32 %A, 3 ; <i32> [#uses=1]
%C = xor i32 %B, 12 ; <i32> [#uses=2]
; additional use of C
store i32 %C, i32* %P
; %C = and uint %B, 3 --> 3
%D = and i32 %C, 3 ; <i32> [#uses=1]
ret i32 %D
}
define i1 @test12(i32 %A, i32 %B) {
%C1 = icmp ult i32 %A, %B ; <i1> [#uses=1]
%C2 = icmp ule i32 %A, %B ; <i1> [#uses=1]
; (A < B) & (A <= B) === (A < B)
%D = and i1 %C1, %C2 ; <i1> [#uses=1]
ret i1 %D
}
define i1 @test13(i32 %A, i32 %B) {
%C1 = icmp ult i32 %A, %B ; <i1> [#uses=1]
%C2 = icmp ugt i32 %A, %B ; <i1> [#uses=1]
; (A < B) & (A > B) === false
%D = and i1 %C1, %C2 ; <i1> [#uses=1]
ret i1 %D
}
define i1 @test14(i8 %A) {
%B = and i8 %A, -128 ; <i8> [#uses=1]
%C = icmp ne i8 %B, 0 ; <i1> [#uses=1]
ret i1 %C
}
define i8 @test15(i8 %A) {
%B = lshr i8 %A, 7 ; <i8> [#uses=1]
; Always equals zero
%C = and i8 %B, 2 ; <i8> [#uses=1]
ret i8 %C
}
define i8 @test16(i8 %A) {
%B = shl i8 %A, 2 ; <i8> [#uses=1]
%C = and i8 %B, 3 ; <i8> [#uses=1]
ret i8 %C
}
;; ~(~X & Y) --> (X | ~Y)
define i8 @test17(i8 %X, i8 %Y) {
%B = xor i8 %X, -1 ; <i8> [#uses=1]
%C = and i8 %B, %Y ; <i8> [#uses=1]
%D = xor i8 %C, -1 ; <i8> [#uses=1]
ret i8 %D
}
define i1 @test18(i32 %A) {
%B = and i32 %A, -128 ; <i32> [#uses=1]
;; C >= 128
%C = icmp ne i32 %B, 0 ; <i1> [#uses=1]
ret i1 %C
}
define i1 @test18a(i8 %A) {
%B = and i8 %A, -2 ; <i8> [#uses=1]
%C = icmp eq i8 %B, 0 ; <i1> [#uses=1]
ret i1 %C
}
define i32 @test19(i32 %A) {
%B = shl i32 %A, 3 ; <i32> [#uses=1]
;; Clearing a zero bit
%C = and i32 %B, -2 ; <i32> [#uses=1]
ret i32 %C
}
define i8 @test20(i8 %A) {
%C = lshr i8 %A, 7 ; <i8> [#uses=1]
;; Unneeded
%D = and i8 %C, 1 ; <i8> [#uses=1]
ret i8 %D
}
define i1 @test22(i32 %A) {
%B = icmp eq i32 %A, 1 ; <i1> [#uses=1]
%C = icmp sge i32 %A, 3 ; <i1> [#uses=1]
;; false
%D = and i1 %B, %C ; <i1> [#uses=1]
ret i1 %D
}
define i1 @test23(i32 %A) {
%B = icmp sgt i32 %A, 1 ; <i1> [#uses=1]
%C = icmp sle i32 %A, 2 ; <i1> [#uses=1]
;; A == 2
%D = and i1 %B, %C ; <i1> [#uses=1]
ret i1 %D
}
define i1 @test24(i32 %A) {
%B = icmp sgt i32 %A, 1 ; <i1> [#uses=1]
%C = icmp ne i32 %A, 2 ; <i1> [#uses=1]
;; A > 2
%D = and i1 %B, %C ; <i1> [#uses=1]
ret i1 %D
}
define i1 @test25(i32 %A) {
%B = icmp sge i32 %A, 50 ; <i1> [#uses=1]
%C = icmp slt i32 %A, 100 ; <i1> [#uses=1]
;; (A-50) <u 50
%D = and i1 %B, %C ; <i1> [#uses=1]
ret i1 %D
}
define i1 @test26(i32 %A) {
%B = icmp ne i32 %A, 49 ; <i1> [#uses=1]
%C = icmp ne i32 %A, 50 ; <i1> [#uses=1]
;; (A-49) > 1
%D = and i1 %B, %C ; <i1> [#uses=1]
ret i1 %D
}
define i8 @test27(i8 %A) {
%B = and i8 %A, 4 ; <i8> [#uses=1]
%C = sub i8 %B, 16 ; <i8> [#uses=1]
;; 0xF0
%D = and i8 %C, -16 ; <i8> [#uses=1]
%E = add i8 %D, 16 ; <i8> [#uses=1]
ret i8 %E
}
;; This is juse a zero extending shr.
define i32 @test28(i32 %X) {
;; Sign extend
%Y = ashr i32 %X, 24 ; <i32> [#uses=1]
;; Mask out sign bits
%Z = and i32 %Y, 255 ; <i32> [#uses=1]
ret i32 %Z
}
define i32 @test29(i8 %X) {
%Y = zext i8 %X to i32 ; <i32> [#uses=1]
;; Zero extend makes this unneeded.
%Z = and i32 %Y, 255 ; <i32> [#uses=1]
ret i32 %Z
}
define i32 @test30(i1 %X) {
%Y = zext i1 %X to i32 ; <i32> [#uses=1]
%Z = and i32 %Y, 1 ; <i32> [#uses=1]
ret i32 %Z
}
define i32 @test31(i1 %X) {
%Y = zext i1 %X to i32 ; <i32> [#uses=1]
%Z = shl i32 %Y, 4 ; <i32> [#uses=1]
%A = and i32 %Z, 16 ; <i32> [#uses=1]
ret i32 %A
}
define i32 @test32(i32 %In) {
%Y = and i32 %In, 16 ; <i32> [#uses=1]
%Z = lshr i32 %Y, 2 ; <i32> [#uses=1]
%A = and i32 %Z, 1 ; <i32> [#uses=1]
ret i32 %A
}
;; Code corresponding to one-bit bitfield ^1.
define i32 @test33(i32 %b) {
%tmp.4.mask = and i32 %b, 1 ; <i32> [#uses=1]
%tmp.10 = xor i32 %tmp.4.mask, 1 ; <i32> [#uses=1]
%tmp.12 = and i32 %b, -2 ; <i32> [#uses=1]
%tmp.13 = or i32 %tmp.12, %tmp.10 ; <i32> [#uses=1]
ret i32 %tmp.13
}
define i32 @test34(i32 %A, i32 %B) {
%tmp.2 = or i32 %B, %A ; <i32> [#uses=1]
%tmp.4 = and i32 %tmp.2, %B ; <i32> [#uses=1]
ret i32 %tmp.4
}