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; RUN: opt -instcombine -S < %s | FileCheck %s
; PR5438
; TODO: This should also optimize down.
;define i32 @test1(i32 %a, i32 %b) nounwind readnone {
;entry:
; %0 = icmp sgt i32 %a, -1 ; <i1> [#uses=1]
; %1 = icmp slt i32 %b, 0 ; <i1> [#uses=1]
; %2 = xor i1 %1, %0 ; <i1> [#uses=1]
; %3 = zext i1 %2 to i32 ; <i32> [#uses=1]
; ret i32 %3
;}
; TODO: This optimizes partially but not all the way.
;define i32 @test2(i32 %a, i32 %b) nounwind readnone {
;entry:
; %0 = and i32 %a, 8 ;<i32> [#uses=1]
; %1 = and i32 %b, 8 ;<i32> [#uses=1]
; %2 = icmp eq i32 %0, %1 ;<i1> [#uses=1]
; %3 = zext i1 %2 to i32 ;<i32> [#uses=1]
; ret i32 %3
;}
define i32 @test3(i32 %a, i32 %b) nounwind readnone {
; CHECK-LABEL: @test3(
entry:
; CHECK: [[XOR1:%.*]] = xor i32 %a, %b
; CHECK: [[SHIFT:%.*]] = lshr i32 [[XOR1]], 31
; CHECK: [[XOR2:%.*]] = xor i32 [[SHIFT]], 1
%0 = lshr i32 %a, 31 ; <i32> [#uses=1]
%1 = lshr i32 %b, 31 ; <i32> [#uses=1]
%2 = icmp eq i32 %0, %1 ; <i1> [#uses=1]
%3 = zext i1 %2 to i32 ; <i32> [#uses=1]
ret i32 %3
; CHECK-NOT: icmp
; CHECK-NOT: zext
; CHECK: ret i32 [[XOR2]]
}
; Variation on @test3: checking the 2nd bit in a situation where the 5th bit
; is one, not zero.
define i32 @test3i(i32 %a, i32 %b) nounwind readnone {
; CHECK-LABEL: @test3i(
entry:
; CHECK: xor i32 %a, %b
; CHECK: lshr i32 %0, 31
; CHECK: xor i32 %1, 1
%0 = lshr i32 %a, 29 ; <i32> [#uses=1]
%1 = lshr i32 %b, 29 ; <i32> [#uses=1]
%2 = or i32 %0, 35
%3 = or i32 %1, 35
%4 = icmp eq i32 %2, %3 ; <i1> [#uses=1]
%5 = zext i1 %4 to i32 ; <i32> [#uses=1]
ret i32 %5
; CHECK-NOT: icmp
; CHECK-NOT: zext
; CHECK: ret i32 %2
}
define i1 @test4a(i32 %a) {
; CHECK-LABEL: @test4a(
entry:
; CHECK: %c = icmp slt i32 %a, 1
; CHECK-NEXT: ret i1 %c
%l = ashr i32 %a, 31
%na = sub i32 0, %a
%r = lshr i32 %na, 31
%signum = or i32 %l, %r
%c = icmp slt i32 %signum, 1
ret i1 %c
}
define i1 @test4b(i64 %a) {
; CHECK-LABEL: @test4b(
entry:
; CHECK: %c = icmp slt i64 %a, 1
; CHECK-NEXT: ret i1 %c
%l = ashr i64 %a, 63
%na = sub i64 0, %a
%r = lshr i64 %na, 63
%signum = or i64 %l, %r
%c = icmp slt i64 %signum, 1
ret i1 %c
}
define i1 @test4c(i64 %a) {
; CHECK-LABEL: @test4c(
entry:
; CHECK: %c = icmp slt i64 %a, 1
; CHECK-NEXT: ret i1 %c
%l = ashr i64 %a, 63
%na = sub i64 0, %a
%r = lshr i64 %na, 63
%signum = or i64 %l, %r
%signum.trunc = trunc i64 %signum to i32
%c = icmp slt i32 %signum.trunc, 1
ret i1 %c
}
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