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|
; RUN: opt -instcombine -value-tracking-dom-conditions=1 -S < %s | FileCheck %s
target datalayout = "e-p:64:64:64-p1:16:16:16-p2:32:32:32-p3:64:64:64-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 i1 @test_cmp_ult(i64 %A) {
; CHECK-LABEL: @test_cmp_ult
entry:
%cmp = icmp ult i64 %A, 64
br i1 %cmp, label %taken, label %untaken
taken:
; CHECK-LABEL: taken:
; CHECK-NEXT: ret i1 false
%cmp2 = icmp ugt i64 %A, 64
ret i1 %cmp2
untaken:
ret i1 true
}
define i1 @test_cmp_ule(i64 %A) {
; CHECK-LABEL: @test_cmp_ule
entry:
%cmp = icmp ule i64 %A, 64
br i1 %cmp, label %taken, label %untaken
taken:
; CHECK-LABEL: taken:
; CHECK-NEXT: ret i1 false
%cmp2 = icmp ugt i64 %A, 128
ret i1 %cmp2
untaken:
ret i1 true
}
define i1 @test_cmp_sgt(i32 %A) {
; CHECK-LABEL: @test_cmp_sgt
entry:
%cmp = icmp sgt i32 %A, 10
br i1 %cmp, label %taken, label %untaken
taken:
; CHECK-LABEL: taken:
; CHECK-NEXT: ret i1 true
%cmp2 = icmp sgt i32 %A, -1
ret i1 %cmp2
untaken:
ret i1 true
}
define i64 @test_add_zero_bits(i64 %A) {
; CHECK-LABEL: @test_add_zero_bits
entry:
%cmp = icmp eq i64 %A, 2
br i1 %cmp, label %taken, label %untaken
taken:
; CHECK-LABEL: taken:
; CHECK-NEXT: ret i64 3
%add = add i64 %A, 1
ret i64 %add
untaken:
ret i64 %A
}
define i64 @test_add_nsw(i64 %A) {
; CHECK-LABEL: @test_add_nsw
entry:
%cmp = icmp ult i64 %A, 20
br i1 %cmp, label %taken, label %untaken
taken:
; CHECK-LABEL: taken:
; CHECK-NEXT: %add = add nuw nsw i64 %A, 1
; CHECK-NEXT: ret i64 %add
%add = add i64 %A, 1
ret i64 %add
untaken:
ret i64 %A
}
; After sinking the instructions into the if block, check that we
; can simplify some of them using dominating conditions.
define i32 @test_add_zero_bits_sink(i32 %x) nounwind ssp {
; CHECK-LABEL: @test_add_zero_bits_sink(
; CHECK-NOT: sdiv i32
entry:
%a = add nsw i32 %x, 16
%b = sdiv i32 %a, %x
%cmp = icmp ult i32 %x, 7
br i1 %cmp, label %bb1, label %bb2
bb1:
; CHECK-LABEL: bb1:
; CHECK-NEXT: or i32 %x, 16
; CHECK-NEXT: udiv i32
ret i32 %b
bb2:
ret i32 %x
}
; A condition in the same block gives no information
define i32 @test_neg1(i32 %x) nounwind ssp {
; CHECK-LABEL: @test_neg1
; CHECK: add
; CHECK: sdiv
; CHECK: icmp
; CHECK: select
entry:
%a = add nsw i32 %x, 16
%b = sdiv i32 %a, %x
%cmp = icmp ult i32 %x, 7
%ret = select i1 %cmp, i32 %a, i32 %b
ret i32 %ret
}
; A non-dominating edge gives no information
define i32 @test_neg2(i32 %x) {
; CHECK-LABEL: @test_neg2
entry:
%cmp = icmp ult i32 %x, 7
br i1 %cmp, label %bb1, label %merge
bb1:
br label %merge
merge:
; CHECK-LABEL: merge:
; CHECK: icmp
; CHECK: select
%cmp2 = icmp ult i32 %x, 7
%ret = select i1 %cmp2, i32 %x, i32 0
ret i32 %ret
}
; A unconditional branch expressed as a condition one gives no
; information (and shouldn't trip any asserts.)
define i32 @test_neg3(i32 %x) {
; CHECK-LABEL: @test_neg3
entry:
%cmp = icmp ult i32 %x, 7
br i1 %cmp, label %merge, label %merge
merge:
; CHECK-LABEL: merge:
; CHECK: icmp
; CHECK: select
%cmp2 = icmp ult i32 %x, 7
%ret = select i1 %cmp2, i32 %x, i32 0
ret i32 %ret
}
declare i32 @bar()
|
