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|
; RUN: opt %s -S -simplifycfg | FileCheck %s
declare void @foo()
declare void @bar()
; CHECK-LABEL: @test_and1
; CHECK: taken:
; CHECK-NOT: cmp3
; CHECK: call void @bar()
; CHECK-NEXT: call void @foo()
; CHECK: ret
define void @test_and1(i32 %a, i32 %b) {
entry:
%cmp1 = icmp eq i32 %a, 0
%cmp2 = icmp eq i32 %b, 0
%and = and i1 %cmp1, %cmp2
br i1 %and, label %taken, label %end
taken:
call void @bar()
%cmp3 = icmp eq i32 %a, 0 ;; <-- implied true
br i1 %cmp3, label %if.then, label %end
if.then:
call void @foo()
br label %end
end:
ret void
}
; We can't infer anything if the result of the 'and' is false
; CHECK-LABEL: @test_and2
; CHECK: taken:
; CHECK: call void @bar()
; CHECK: %cmp3
; CHECK: br i1 %cmp3
; CHECK: if.then:
; CHECK: call void @foo()
; CHECK: ret
define void @test_and2(i32 %a, i32 %b) {
entry:
%cmp1 = icmp eq i32 %a, 0
%cmp2 = icmp eq i32 %b, 0
%and = and i1 %cmp1, %cmp2
br i1 %and, label %end, label %taken
taken:
call void @bar()
%cmp3 = icmp eq i32 %a, 0
br i1 %cmp3, label %if.then, label %end
if.then:
call void @foo()
br label %end
end:
ret void
}
; CHECK-LABEL: @test_or1
; CHECK: taken:
; CHECK-NOT: cmp3
; CHECK: call void @bar()
; CHECK-NEXT: call void @foo()
; CHECK: ret
define void @test_or1(i32 %a, i32 %b) {
entry:
%cmp1 = icmp eq i32 %a, 0
%cmp2 = icmp eq i32 %b, 0
%or = or i1 %cmp1, %cmp2
br i1 %or, label %end, label %taken
taken:
call void @bar()
%cmp3 = icmp ne i32 %a, 0 ;; <-- implied true
br i1 %cmp3, label %if.then, label %end
if.then:
call void @foo()
br label %end
end:
ret void
}
; We can't infer anything if the result of the 'or' is true
; CHECK-LABEL: @test_or2
; CHECK: call void @bar()
; CHECK: %cmp3
; CHECK: br i1 %cmp3
; CHECK: if.then:
; CHECK: call void @foo()
; CHECK: ret
define void @test_or2(i32 %a, i32 %b) {
entry:
%cmp1 = icmp eq i32 %a, 0
%cmp2 = icmp eq i32 %b, 0
%or = or i1 %cmp1, %cmp2
br i1 %or, label %taken, label %end
taken:
call void @bar()
%cmp3 = icmp eq i32 %a, 0
br i1 %cmp3, label %if.then, label %end
if.then:
call void @foo()
br label %end
end:
ret void
}
; We can recurse a tree of 'and' or 'or's.
; CHECK-LABEL: @test_and_recurse1
; CHECK: taken:
; CHECK-NEXT: call void @bar()
; CHECK-NEXT: call void @foo()
; CHECK-NEXT: br label %end
; CHECK: ret
define void @test_and_recurse1(i32 %a, i32 %b, i32 %c) {
entry:
%cmpa = icmp eq i32 %a, 0
%cmpb = icmp eq i32 %b, 0
%cmpc = icmp eq i32 %c, 0
%and1 = and i1 %cmpa, %cmpb
%and2 = and i1 %and1, %cmpc
br i1 %and2, label %taken, label %end
taken:
call void @bar()
%cmp3 = icmp eq i32 %a, 0
br i1 %cmp3, label %if.then, label %end
if.then:
call void @foo()
br label %end
end:
ret void
}
; Check to make sure we don't recurse too deep.
; CHECK-LABEL: @test_and_recurse2
; CHECK: taken:
; CHECK-NEXT: call void @bar()
; CHECK-NEXT: %cmp3 = icmp eq i32 %a, 0
; CHECK-NEXT: br i1 %cmp3, label %if.then, label %end
; CHECK: ret
define void @test_and_recurse2(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e, i32 %f,
i32 %g, i32 %h) {
entry:
%cmpa = icmp eq i32 %a, 0
%cmpb = icmp eq i32 %b, 0
%cmpc = icmp eq i32 %c, 0
%cmpd = icmp eq i32 %d, 0
%cmpe = icmp eq i32 %e, 0
%cmpf = icmp eq i32 %f, 0
%cmpg = icmp eq i32 %g, 0
%cmph = icmp eq i32 %h, 0
%and1 = and i1 %cmpa, %cmpb
%and2 = and i1 %and1, %cmpc
%and3 = and i1 %and2, %cmpd
%and4 = and i1 %and3, %cmpe
%and5 = and i1 %and4, %cmpf
%and6 = and i1 %and5, %cmpg
%and7 = and i1 %and6, %cmph
br i1 %and7, label %taken, label %end
taken:
call void @bar()
%cmp3 = icmp eq i32 %a, 0 ; <-- can be implied true
br i1 %cmp3, label %if.then, label %end
if.then:
call void @foo()
br label %end
end:
ret void
}
|
