llvm-6502/test/Transforms/InstCombine/icmp.ll
Benjamin Kramer 66821d9020 InstCombine: Turn (zext A) == (B & (1<<X)-1) into A == (trunc B), narrowing the compare.
This saves a cast, and zext is more expensive on platforms with subreg support
than trunc is. This occurs in the BSD implementation of memchr(3), see PR12750.
On the synthetic benchmark from that bug stupid_memchr and bsd_memchr have the
same performance now when not inlining either function.

stupid_memchr: 323.0us
bsd_memchr: 321.0us
memchr: 479.0us

where memchr is the llvm-gcc compiled bsd_memchr from osx lion's libc. When
inlining is enabled bsd_memchr still regresses down to llvm-gcc memchr time,
I haven't fully understood the issue yet, something is grossly mangling the
loop after inlining.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158297 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-10 20:35:00 +00:00

662 lines
14 KiB
LLVM

; RUN: opt < %s -instcombine -S | FileCheck %s
target datalayout =
"e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
define i32 @test1(i32 %X) {
entry:
icmp slt i32 %X, 0 ; <i1>:0 [#uses=1]
zext i1 %0 to i32 ; <i32>:1 [#uses=1]
ret i32 %1
; CHECK: @test1
; CHECK: lshr i32 %X, 31
; CHECK-NEXT: ret i32
}
define i32 @test2(i32 %X) {
entry:
icmp ult i32 %X, -2147483648 ; <i1>:0 [#uses=1]
zext i1 %0 to i32 ; <i32>:1 [#uses=1]
ret i32 %1
; CHECK: @test2
; CHECK: lshr i32 %X, 31
; CHECK-NEXT: xor i32
; CHECK-NEXT: ret i32
}
define i32 @test3(i32 %X) {
entry:
icmp slt i32 %X, 0 ; <i1>:0 [#uses=1]
sext i1 %0 to i32 ; <i32>:1 [#uses=1]
ret i32 %1
; CHECK: @test3
; CHECK: ashr i32 %X, 31
; CHECK-NEXT: ret i32
}
define i32 @test4(i32 %X) {
entry:
icmp ult i32 %X, -2147483648 ; <i1>:0 [#uses=1]
sext i1 %0 to i32 ; <i32>:1 [#uses=1]
ret i32 %1
; CHECK: @test4
; CHECK: ashr i32 %X, 31
; CHECK-NEXT: xor i32
; CHECK-NEXT: ret i32
}
; PR4837
define <2 x i1> @test5(<2 x i64> %x) {
entry:
%V = icmp eq <2 x i64> %x, undef
ret <2 x i1> %V
; CHECK: @test5
; CHECK: ret <2 x i1> <i1 true, i1 true>
}
define i32 @test6(i32 %a, i32 %b) {
%c = icmp sle i32 %a, -1
%d = zext i1 %c to i32
%e = sub i32 0, %d
%f = and i32 %e, %b
ret i32 %f
; CHECK: @test6
; CHECK-NEXT: ashr i32 %a, 31
; CHECK-NEXT: %f = and i32 %e, %b
; CHECK-NEXT: ret i32 %f
}
define i1 @test7(i32 %x) {
entry:
%a = add i32 %x, -1
%b = icmp ult i32 %a, %x
ret i1 %b
; CHECK: @test7
; CHECK: %b = icmp ne i32 %x, 0
; CHECK: ret i1 %b
}
define i1 @test8(i32 %x){
entry:
%a = add i32 %x, -1
%b = icmp eq i32 %a, %x
ret i1 %b
; CHECK: @test8
; CHECK: ret i1 false
}
define i1 @test9(i32 %x) {
entry:
%a = add i32 %x, -2
%b = icmp ugt i32 %x, %a
ret i1 %b
; CHECK: @test9
; CHECK: icmp ugt i32 %x, 1
; CHECK: ret i1 %b
}
define i1 @test10(i32 %x){
entry:
%a = add i32 %x, -1
%b = icmp slt i32 %a, %x
ret i1 %b
; CHECK: @test10
; CHECK: %b = icmp ne i32 %x, -2147483648
; CHECK: ret i1 %b
}
define i1 @test11(i32 %x) {
%a = add nsw i32 %x, 8
%b = icmp slt i32 %x, %a
ret i1 %b
; CHECK: @test11
; CHECK: ret i1 true
}
; PR6195
define i1 @test12(i1 %A) {
%S = select i1 %A, i64 -4294967295, i64 8589934591
%B = icmp ne i64 bitcast (<2 x i32> <i32 1, i32 -1> to i64), %S
ret i1 %B
; CHECK: @test12
; CHECK-NEXT: = xor i1 %A, true
; CHECK-NEXT: ret i1
}
; PR6481
define i1 @test13(i8 %X) nounwind readnone {
entry:
%cmp = icmp slt i8 undef, %X
ret i1 %cmp
; CHECK: @test13
; CHECK: ret i1 false
}
define i1 @test14(i8 %X) nounwind readnone {
entry:
%cmp = icmp slt i8 undef, -128
ret i1 %cmp
; CHECK: @test14
; CHECK: ret i1 false
}
define i1 @test15() nounwind readnone {
entry:
%cmp = icmp eq i8 undef, -128
ret i1 %cmp
; CHECK: @test15
; CHECK: ret i1 undef
}
define i1 @test16() nounwind readnone {
entry:
%cmp = icmp ne i8 undef, -128
ret i1 %cmp
; CHECK: @test16
; CHECK: ret i1 undef
}
define i1 @test17(i32 %x) nounwind {
%shl = shl i32 1, %x
%and = and i32 %shl, 8
%cmp = icmp eq i32 %and, 0
ret i1 %cmp
; CHECK: @test17
; CHECK-NEXT: %cmp = icmp ne i32 %x, 3
}
define i1 @test18(i32 %x) nounwind {
%sh = lshr i32 8, %x
%and = and i32 %sh, 1
%cmp = icmp eq i32 %and, 0
ret i1 %cmp
; CHECK: @test18
; CHECK-NEXT: %cmp = icmp ne i32 %x, 3
}
define i1 @test19(i32 %x) nounwind {
%shl = shl i32 1, %x
%and = and i32 %shl, 8
%cmp = icmp eq i32 %and, 8
ret i1 %cmp
; CHECK: @test19
; CHECK-NEXT: %cmp = icmp eq i32 %x, 3
}
define i1 @test20(i32 %x) nounwind {
%shl = shl i32 1, %x
%and = and i32 %shl, 8
%cmp = icmp ne i32 %and, 0
ret i1 %cmp
; CHECK: @test20
; CHECK-NEXT: %cmp = icmp eq i32 %x, 3
}
define i1 @test21(i8 %x, i8 %y) {
; CHECK: @test21
; CHECK-NOT: or i8
; CHECK: icmp ugt
%A = or i8 %x, 1
%B = icmp ugt i8 %A, 3
ret i1 %B
}
define i1 @test22(i8 %x, i8 %y) {
; CHECK: @test22
; CHECK-NOT: or i8
; CHECK: icmp ult
%A = or i8 %x, 1
%B = icmp ult i8 %A, 4
ret i1 %B
}
; PR2740
; CHECK: @test23
; CHECK: icmp sgt i32 %x, 1328634634
define i1 @test23(i32 %x) nounwind {
%i3 = sdiv i32 %x, -1328634635
%i4 = icmp eq i32 %i3, -1
ret i1 %i4
}
@X = global [1000 x i32] zeroinitializer
; PR8882
; CHECK: @test24
; CHECK: %cmp = icmp eq i64 %i, 1000
; CHECK: ret i1 %cmp
define i1 @test24(i64 %i) {
%p1 = getelementptr inbounds i32* getelementptr inbounds ([1000 x i32]* @X, i64 0, i64 0), i64 %i
%cmp = icmp eq i32* %p1, getelementptr inbounds ([1000 x i32]* @X, i64 1, i64 0)
ret i1 %cmp
}
; CHECK: @test25
; X + Z > Y + Z -> X > Y if there is no overflow.
; CHECK: %c = icmp sgt i32 %x, %y
; CHECK: ret i1 %c
define i1 @test25(i32 %x, i32 %y, i32 %z) {
%lhs = add nsw i32 %x, %z
%rhs = add nsw i32 %y, %z
%c = icmp sgt i32 %lhs, %rhs
ret i1 %c
}
; CHECK: @test26
; X + Z > Y + Z -> X > Y if there is no overflow.
; CHECK: %c = icmp ugt i32 %x, %y
; CHECK: ret i1 %c
define i1 @test26(i32 %x, i32 %y, i32 %z) {
%lhs = add nuw i32 %x, %z
%rhs = add nuw i32 %y, %z
%c = icmp ugt i32 %lhs, %rhs
ret i1 %c
}
; CHECK: @test27
; X - Z > Y - Z -> X > Y if there is no overflow.
; CHECK: %c = icmp sgt i32 %x, %y
; CHECK: ret i1 %c
define i1 @test27(i32 %x, i32 %y, i32 %z) {
%lhs = sub nsw i32 %x, %z
%rhs = sub nsw i32 %y, %z
%c = icmp sgt i32 %lhs, %rhs
ret i1 %c
}
; CHECK: @test28
; X - Z > Y - Z -> X > Y if there is no overflow.
; CHECK: %c = icmp ugt i32 %x, %y
; CHECK: ret i1 %c
define i1 @test28(i32 %x, i32 %y, i32 %z) {
%lhs = sub nuw i32 %x, %z
%rhs = sub nuw i32 %y, %z
%c = icmp ugt i32 %lhs, %rhs
ret i1 %c
}
; CHECK: @test29
; X + Y > X -> Y > 0 if there is no overflow.
; CHECK: %c = icmp sgt i32 %y, 0
; CHECK: ret i1 %c
define i1 @test29(i32 %x, i32 %y) {
%lhs = add nsw i32 %x, %y
%c = icmp sgt i32 %lhs, %x
ret i1 %c
}
; CHECK: @test30
; X + Y > X -> Y > 0 if there is no overflow.
; CHECK: %c = icmp ne i32 %y, 0
; CHECK: ret i1 %c
define i1 @test30(i32 %x, i32 %y) {
%lhs = add nuw i32 %x, %y
%c = icmp ugt i32 %lhs, %x
ret i1 %c
}
; CHECK: @test31
; X > X + Y -> 0 > Y if there is no overflow.
; CHECK: %c = icmp slt i32 %y, 0
; CHECK: ret i1 %c
define i1 @test31(i32 %x, i32 %y) {
%rhs = add nsw i32 %x, %y
%c = icmp sgt i32 %x, %rhs
ret i1 %c
}
; CHECK: @test32
; X > X + Y -> 0 > Y if there is no overflow.
; CHECK: ret i1 false
define i1 @test32(i32 %x, i32 %y) {
%rhs = add nuw i32 %x, %y
%c = icmp ugt i32 %x, %rhs
ret i1 %c
}
; CHECK: @test33
; X - Y > X -> 0 > Y if there is no overflow.
; CHECK: %c = icmp slt i32 %y, 0
; CHECK: ret i1 %c
define i1 @test33(i32 %x, i32 %y) {
%lhs = sub nsw i32 %x, %y
%c = icmp sgt i32 %lhs, %x
ret i1 %c
}
; CHECK: @test34
; X - Y > X -> 0 > Y if there is no overflow.
; CHECK: ret i1 false
define i1 @test34(i32 %x, i32 %y) {
%lhs = sub nuw i32 %x, %y
%c = icmp ugt i32 %lhs, %x
ret i1 %c
}
; CHECK: @test35
; X > X - Y -> Y > 0 if there is no overflow.
; CHECK: %c = icmp sgt i32 %y, 0
; CHECK: ret i1 %c
define i1 @test35(i32 %x, i32 %y) {
%rhs = sub nsw i32 %x, %y
%c = icmp sgt i32 %x, %rhs
ret i1 %c
}
; CHECK: @test36
; X > X - Y -> Y > 0 if there is no overflow.
; CHECK: %c = icmp ne i32 %y, 0
; CHECK: ret i1 %c
define i1 @test36(i32 %x, i32 %y) {
%rhs = sub nuw i32 %x, %y
%c = icmp ugt i32 %x, %rhs
ret i1 %c
}
; CHECK: @test37
; X - Y > X - Z -> Z > Y if there is no overflow.
; CHECK: %c = icmp sgt i32 %z, %y
; CHECK: ret i1 %c
define i1 @test37(i32 %x, i32 %y, i32 %z) {
%lhs = sub nsw i32 %x, %y
%rhs = sub nsw i32 %x, %z
%c = icmp sgt i32 %lhs, %rhs
ret i1 %c
}
; CHECK: @test38
; X - Y > X - Z -> Z > Y if there is no overflow.
; CHECK: %c = icmp ugt i32 %z, %y
; CHECK: ret i1 %c
define i1 @test38(i32 %x, i32 %y, i32 %z) {
%lhs = sub nuw i32 %x, %y
%rhs = sub nuw i32 %x, %z
%c = icmp ugt i32 %lhs, %rhs
ret i1 %c
}
; PR9343 #1
; CHECK: @test39
; CHECK: %B = icmp eq i32 %X, 0
define i1 @test39(i32 %X, i32 %Y) {
%A = ashr exact i32 %X, %Y
%B = icmp eq i32 %A, 0
ret i1 %B
}
; CHECK: @test40
; CHECK: %B = icmp ne i32 %X, 0
define i1 @test40(i32 %X, i32 %Y) {
%A = lshr exact i32 %X, %Y
%B = icmp ne i32 %A, 0
ret i1 %B
}
; PR9343 #3
; CHECK: @test41
; CHECK: ret i1 true
define i1 @test41(i32 %X, i32 %Y) {
%A = urem i32 %X, %Y
%B = icmp ugt i32 %Y, %A
ret i1 %B
}
; CHECK: @test42
; CHECK: %B = icmp sgt i32 %Y, -1
define i1 @test42(i32 %X, i32 %Y) {
%A = srem i32 %X, %Y
%B = icmp slt i32 %A, %Y
ret i1 %B
}
; CHECK: @test43
; CHECK: %B = icmp slt i32 %Y, 0
define i1 @test43(i32 %X, i32 %Y) {
%A = srem i32 %X, %Y
%B = icmp slt i32 %Y, %A
ret i1 %B
}
; CHECK: @test44
; CHECK: %B = icmp sgt i32 %Y, -1
define i1 @test44(i32 %X, i32 %Y) {
%A = srem i32 %X, %Y
%B = icmp slt i32 %A, %Y
ret i1 %B
}
; CHECK: @test45
; CHECK: %B = icmp slt i32 %Y, 0
define i1 @test45(i32 %X, i32 %Y) {
%A = srem i32 %X, %Y
%B = icmp slt i32 %Y, %A
ret i1 %B
}
; PR9343 #4
; CHECK: @test46
; CHECK: %C = icmp ult i32 %X, %Y
define i1 @test46(i32 %X, i32 %Y, i32 %Z) {
%A = ashr exact i32 %X, %Z
%B = ashr exact i32 %Y, %Z
%C = icmp ult i32 %A, %B
ret i1 %C
}
; PR9343 #5
; CHECK: @test47
; CHECK: %C = icmp ugt i32 %X, %Y
define i1 @test47(i32 %X, i32 %Y, i32 %Z) {
%A = ashr exact i32 %X, %Z
%B = ashr exact i32 %Y, %Z
%C = icmp ugt i32 %A, %B
ret i1 %C
}
; PR9343 #8
; CHECK: @test48
; CHECK: %C = icmp eq i32 %X, %Y
define i1 @test48(i32 %X, i32 %Y, i32 %Z) {
%A = sdiv exact i32 %X, %Z
%B = sdiv exact i32 %Y, %Z
%C = icmp eq i32 %A, %B
ret i1 %C
}
; PR8469
; CHECK: @test49
; CHECK: ret <2 x i1> <i1 true, i1 true>
define <2 x i1> @test49(<2 x i32> %tmp3) {
entry:
%tmp11 = and <2 x i32> %tmp3, <i32 3, i32 3>
%cmp = icmp ult <2 x i32> %tmp11, <i32 4, i32 4>
ret <2 x i1> %cmp
}
; PR9343 #7
; CHECK: @test50
; CHECK: ret i1 true
define i1 @test50(i16 %X, i32 %Y) {
%A = zext i16 %X to i32
%B = srem i32 %A, %Y
%C = icmp sgt i32 %B, -1
ret i1 %C
}
; CHECK: @test51
; CHECK: ret i1 %C
define i1 @test51(i32 %X, i32 %Y) {
%A = and i32 %X, 2147483648
%B = srem i32 %A, %Y
%C = icmp sgt i32 %B, -1
ret i1 %C
}
; CHECK: @test52
; CHECK-NEXT: and i32 %x1, 16711935
; CHECK-NEXT: icmp eq i32 {{.*}}, 4980863
; CHECK-NEXT: ret i1
define i1 @test52(i32 %x1) nounwind {
%conv = and i32 %x1, 255
%cmp = icmp eq i32 %conv, 127
%tmp2 = lshr i32 %x1, 16
%tmp3 = trunc i32 %tmp2 to i8
%cmp15 = icmp eq i8 %tmp3, 76
%A = and i1 %cmp, %cmp15
ret i1 %A
}
; PR9838
; CHECK: @test53
; CHECK-NEXT: ashr exact
; CHECK-NEXT: ashr
; CHECK-NEXT: icmp
define i1 @test53(i32 %a, i32 %b) nounwind {
%x = ashr exact i32 %a, 30
%y = ashr i32 %b, 30
%z = icmp eq i32 %x, %y
ret i1 %z
}
; CHECK: @test54
; CHECK-NEXT: %and = and i8 %a, -64
; CHECK-NEXT: icmp eq i8 %and, -128
define i1 @test54(i8 %a) nounwind {
%ext = zext i8 %a to i32
%and = and i32 %ext, 192
%ret = icmp eq i32 %and, 128
ret i1 %ret
}
; CHECK: @test55
; CHECK-NEXT: icmp eq i32 %a, -123
define i1 @test55(i32 %a) {
%sub = sub i32 0, %a
%cmp = icmp eq i32 %sub, 123
ret i1 %cmp
}
; CHECK: @test56
; CHECK-NEXT: icmp eq i32 %a, -113
define i1 @test56(i32 %a) {
%sub = sub i32 10, %a
%cmp = icmp eq i32 %sub, 123
ret i1 %cmp
}
; PR10267 Don't make icmps more expensive when no other inst is subsumed.
declare void @foo(i32)
; CHECK: @test57
; CHECK: %and = and i32 %a, -2
; CHECK: %cmp = icmp ne i32 %and, 0
define i1 @test57(i32 %a) {
%and = and i32 %a, -2
%cmp = icmp ne i32 %and, 0
call void @foo(i32 %and)
ret i1 %cmp
}
; rdar://problem/10482509
; CHECK: @cmpabs1
; CHECK-NEXT: icmp ne
define zeroext i1 @cmpabs1(i64 %val) {
%sub = sub nsw i64 0, %val
%cmp = icmp slt i64 %val, 0
%sub.val = select i1 %cmp, i64 %sub, i64 %val
%tobool = icmp ne i64 %sub.val, 0
ret i1 %tobool
}
; CHECK: @cmpabs2
; CHECK-NEXT: icmp ne
define zeroext i1 @cmpabs2(i64 %val) {
%sub = sub nsw i64 0, %val
%cmp = icmp slt i64 %val, 0
%sub.val = select i1 %cmp, i64 %val, i64 %sub
%tobool = icmp ne i64 %sub.val, 0
ret i1 %tobool
}
; CHECK: @test58
; CHECK-NEXT: call i32 @test58_d(i64 36029346783166592)
define void @test58() nounwind {
%cast = bitcast <1 x i64> <i64 36029346783166592> to i64
%call = call i32 @test58_d( i64 %cast) nounwind
ret void
}
declare i32 @test58_d(i64)
define i1 @test59(i8* %foo) {
%bit = bitcast i8* %foo to i32*
%gep1 = getelementptr inbounds i32* %bit, i64 2
%gep2 = getelementptr inbounds i8* %foo, i64 10
%cast1 = bitcast i32* %gep1 to i8*
%cmp = icmp ult i8* %cast1, %gep2
%use = ptrtoint i8* %cast1 to i64
%call = call i32 @test58_d(i64 %use) nounwind
ret i1 %cmp
; CHECK: @test59
; CHECK: ret i1 true
}
define i1 @test60(i8* %foo, i64 %i, i64 %j) {
%bit = bitcast i8* %foo to i32*
%gep1 = getelementptr inbounds i32* %bit, i64 %i
%gep2 = getelementptr inbounds i8* %foo, i64 %j
%cast1 = bitcast i32* %gep1 to i8*
%cmp = icmp ult i8* %cast1, %gep2
ret i1 %cmp
; CHECK: @test60
; CHECK-NEXT: %gep1.idx = shl nuw i64 %i, 2
; CHECK-NEXT: icmp slt i64 %gep1.idx, %j
; CHECK-NEXT: ret i1
}
define i1 @test61(i8* %foo, i64 %i, i64 %j) {
%bit = bitcast i8* %foo to i32*
%gep1 = getelementptr i32* %bit, i64 %i
%gep2 = getelementptr i8* %foo, i64 %j
%cast1 = bitcast i32* %gep1 to i8*
%cmp = icmp ult i8* %cast1, %gep2
ret i1 %cmp
; Don't transform non-inbounds GEPs.
; CHECK: @test61
; CHECK: icmp ult i8* %cast1, %gep2
; CHECK-NEXT: ret i1
}
define i1 @test62(i8* %a) {
%arrayidx1 = getelementptr inbounds i8* %a, i64 1
%arrayidx2 = getelementptr inbounds i8* %a, i64 10
%cmp = icmp slt i8* %arrayidx1, %arrayidx2
ret i1 %cmp
; CHECK: @test62
; CHECK-NEXT: ret i1 true
}
define i1 @test63(i8 %a, i32 %b) nounwind {
%z = zext i8 %a to i32
%t = and i32 %b, 255
%c = icmp eq i32 %z, %t
ret i1 %c
; CHECK: @test63
; CHECK-NEXT: %1 = trunc i32 %b to i8
; CHECK-NEXT: %c = icmp eq i8 %1, %a
; CHECK-NEXT: ret i1 %c
}
define i1 @test64(i8 %a, i32 %b) nounwind {
%t = and i32 %b, 255
%z = zext i8 %a to i32
%c = icmp eq i32 %t, %z
ret i1 %c
; CHECK: @test64
; CHECK-NEXT: %1 = trunc i32 %b to i8
; CHECK-NEXT: %c = icmp eq i8 %1, %a
; CHECK-NEXT: ret i1 %c
}