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| ; RUN: opt < %s -basicaa -gvn -S | FileCheck %s
@a = external global i32 ; <i32*> [#uses=7]
; CHECK-LABEL: @test1(
define i32 @test1() nounwind {
entry:
%0 = load i32, i32* @a, align 4
%1 = icmp eq i32 %0, 4
br i1 %1, label %bb, label %bb1
bb: ; preds = %entry
br label %bb8
bb1: ; preds = %entry
%2 = load i32, i32* @a, align 4
%3 = icmp eq i32 %2, 5
br i1 %3, label %bb2, label %bb3
bb2: ; preds = %bb1
br label %bb8
bb3: ; preds = %bb1
%4 = load i32, i32* @a, align 4
%5 = icmp eq i32 %4, 4
; CHECK: br i1 false, label %bb4, label %bb5
br i1 %5, label %bb4, label %bb5
bb4: ; preds = %bb3
%6 = load i32, i32* @a, align 4
%7 = add i32 %6, 5
br label %bb8
bb5: ; preds = %bb3
%8 = load i32, i32* @a, align 4
%9 = icmp eq i32 %8, 5
; CHECK: br i1 false, label %bb6, label %bb7
br i1 %9, label %bb6, label %bb7
bb6: ; preds = %bb5
%10 = load i32, i32* @a, align 4
%11 = add i32 %10, 4
br label %bb8
bb7: ; preds = %bb5
%12 = load i32, i32* @a, align 4
br label %bb8
bb8: ; preds = %bb7, %bb6, %bb4, %bb2, %bb
%.0 = phi i32 [ %12, %bb7 ], [ %11, %bb6 ], [ %7, %bb4 ], [ 4, %bb2 ], [ 5, %bb ]
br label %return
return: ; preds = %bb8
ret i32 %.0
}
declare void @foo(i1)
declare void @bar(i32)
; CHECK-LABEL: @test3(
define void @test3(i32 %x, i32 %y) {
%xz = icmp eq i32 %x, 0
%yz = icmp eq i32 %y, 0
%z = and i1 %xz, %yz
br i1 %z, label %both_zero, label %nope
both_zero:
call void @foo(i1 %xz)
; CHECK: call void @foo(i1 true)
call void @foo(i1 %yz)
; CHECK: call void @foo(i1 true)
call void @bar(i32 %x)
; CHECK: call void @bar(i32 0)
call void @bar(i32 %y)
; CHECK: call void @bar(i32 0)
ret void
nope:
call void @foo(i1 %z)
; CHECK: call void @foo(i1 false)
ret void
}
; CHECK-LABEL: @test4(
define void @test4(i1 %b, i32 %x) {
br i1 %b, label %sw, label %case3
sw:
switch i32 %x, label %default [
i32 0, label %case0
i32 1, label %case1
i32 2, label %case0
i32 3, label %case3
i32 4, label %default
]
default:
; CHECK: default:
call void @bar(i32 %x)
; CHECK: call void @bar(i32 %x)
ret void
case0:
; CHECK: case0:
call void @bar(i32 %x)
; CHECK: call void @bar(i32 %x)
ret void
case1:
; CHECK: case1:
call void @bar(i32 %x)
; CHECK: call void @bar(i32 1)
ret void
case3:
; CHECK: case3:
call void @bar(i32 %x)
; CHECK: call void @bar(i32 %x)
ret void
}
; CHECK-LABEL: @test5(
define i1 @test5(i32 %x, i32 %y) {
%cmp = icmp eq i32 %x, %y
br i1 %cmp, label %same, label %different
same:
%cmp2 = icmp ne i32 %x, %y
; CHECK: ret i1 false
ret i1 %cmp2
different:
%cmp3 = icmp eq i32 %x, %y
; CHECK: ret i1 false
ret i1 %cmp3
}
; CHECK-LABEL: @test6(
define i1 @test6(i32 %x, i32 %y) {
%cmp2 = icmp ne i32 %x, %y
%cmp = icmp eq i32 %x, %y
%cmp3 = icmp eq i32 %x, %y
br i1 %cmp, label %same, label %different
same:
; CHECK: ret i1 false
ret i1 %cmp2
different:
; CHECK: ret i1 false
ret i1 %cmp3
}
; CHECK-LABEL: @test6_fp(
define i1 @test6_fp(float %x, float %y) {
%cmp2 = fcmp une float %x, %y
%cmp = fcmp oeq float %x, %y
%cmp3 = fcmp oeq float %x, %y
br i1 %cmp, label %same, label %different
same:
; CHECK: ret i1 false
ret i1 %cmp2
different:
; CHECK: ret i1 false
ret i1 %cmp3
}
; CHECK-LABEL: @test7(
define i1 @test7(i32 %x, i32 %y) {
%cmp = icmp sgt i32 %x, %y
br i1 %cmp, label %same, label %different
same:
%cmp2 = icmp sle i32 %x, %y
; CHECK: ret i1 false
ret i1 %cmp2
different:
%cmp3 = icmp sgt i32 %x, %y
; CHECK: ret i1 false
ret i1 %cmp3
}
; CHECK-LABEL: @test7_fp(
define i1 @test7_fp(float %x, float %y) {
%cmp = fcmp ogt float %x, %y
br i1 %cmp, label %same, label %different
same:
%cmp2 = fcmp ule float %x, %y
; CHECK: ret i1 false
ret i1 %cmp2
different:
%cmp3 = fcmp ogt float %x, %y
; CHECK: ret i1 false
ret i1 %cmp3
}
; CHECK-LABEL: @test8(
define i1 @test8(i32 %x, i32 %y) {
%cmp2 = icmp sle i32 %x, %y
%cmp = icmp sgt i32 %x, %y
%cmp3 = icmp sgt i32 %x, %y
br i1 %cmp, label %same, label %different
same:
; CHECK: ret i1 false
ret i1 %cmp2
different:
; CHECK: ret i1 false
ret i1 %cmp3
}
; CHECK-LABEL: @test8_fp(
define i1 @test8_fp(float %x, float %y) {
%cmp2 = fcmp ule float %x, %y
%cmp = fcmp ogt float %x, %y
%cmp3 = fcmp ogt float %x, %y
br i1 %cmp, label %same, label %different
same:
; CHECK: ret i1 false
ret i1 %cmp2
different:
; CHECK: ret i1 false
ret i1 %cmp3
}
; PR1768
; CHECK-LABEL: @test9(
define i32 @test9(i32 %i, i32 %j) {
%cmp = icmp eq i32 %i, %j
br i1 %cmp, label %cond_true, label %ret
cond_true:
%diff = sub i32 %i, %j
ret i32 %diff
; CHECK: ret i32 0
ret:
ret i32 5
; CHECK: ret i32 5
}
; PR1768
; CHECK-LABEL: @test10(
define i32 @test10(i32 %j, i32 %i) {
%cmp = icmp eq i32 %i, %j
br i1 %cmp, label %cond_true, label %ret
cond_true:
%diff = sub i32 %i, %j
ret i32 %diff
; CHECK: ret i32 0
ret:
ret i32 5
; CHECK: ret i32 5
}
declare i32 @yogibar()
; CHECK-LABEL: @test11(
define i32 @test11(i32 %x) {
%v0 = call i32 @yogibar()
%v1 = call i32 @yogibar()
%cmp = icmp eq i32 %v0, %v1
br i1 %cmp, label %cond_true, label %next
cond_true:
ret i32 %v1
; CHECK: ret i32 %v0
next:
%cmp2 = icmp eq i32 %x, %v0
br i1 %cmp2, label %cond_true2, label %next2
cond_true2:
ret i32 %v0
; CHECK: ret i32 %x
next2:
ret i32 0
}
; CHECK-LABEL: @test12(
define i32 @test12(i32 %x) {
%cmp = icmp eq i32 %x, 0
br i1 %cmp, label %cond_true, label %cond_false
cond_true:
br label %ret
cond_false:
br label %ret
ret:
%res = phi i32 [ %x, %cond_true ], [ %x, %cond_false ]
; CHECK: %res = phi i32 [ 0, %cond_true ], [ %x, %cond_false ]
ret i32 %res
}
; On the path from entry->if->end we know that ptr1==ptr2, so we can determine
; that gep2 does not alias ptr1 on that path (as it would require that
; ptr2==ptr2+2), so we can perform PRE of the load.
; CHECK-LABEL: @test13
define i32 @test13(i32* %ptr1, i32* %ptr2) {
; CHECK-LABEL: entry:
entry:
%gep1 = getelementptr i32, i32* %ptr2, i32 1
%gep2 = getelementptr i32, i32* %ptr2, i32 2
%cmp = icmp eq i32* %ptr1, %ptr2
br i1 %cmp, label %if, label %end
; CHECK: [[CRIT_EDGE:.*]]:
; CHECK: %[[PRE:.*]] = load i32, i32* %gep2, align 4
; CHECK-LABEL: if:
if:
%val1 = load i32, i32* %gep2, align 4
br label %end
; CHECK-LABEL: end:
; CHECK: %val2 = phi i32 [ %val1, %if ], [ %[[PRE]], %[[CRIT_EDGE]] ]
; CHECK-NOT: load
end:
%phi1 = phi i32* [ %ptr1, %if ], [ %gep1, %entry ]
%phi2 = phi i32 [ %val1, %if ], [ 0, %entry ]
store i32 0, i32* %phi1, align 4
%val2 = load i32, i32* %gep2, align 4
%ret = add i32 %phi2, %val2
ret i32 %ret
}
; CHECK-LABEL: @test14
define void @test14(i32* %ptr1, i32* noalias %ptr2) {
entry:
%gep1 = getelementptr inbounds i32, i32* %ptr1, i32 1
%gep2 = getelementptr inbounds i32, i32* %ptr1, i32 2
br label %loop
; CHECK-LABEL: loop:
loop:
%phi1 = phi i32* [ %gep3, %loop.end ], [ %gep1, %entry ]
br i1 undef, label %if1, label %then
; CHECK: [[CRIT_EDGE:.*]]:
; CHECK: %[[PRE:.*]] = load i32, i32* %gep2, align 4
; CHECK-LABEL: if1:
; CHECK: %val2 = phi i32 [ %[[PRE]], %[[CRIT_EDGE]] ], [ %val3, %loop.end ]
; CHECK-NOT: load
if1:
%val2 = load i32, i32* %gep2, align 4
store i32 %val2, i32* %gep2, align 4
store i32 0, i32* %phi1, align 4
br label %then
; CHECK-LABEL: then:
then:
%cmp = icmp eq i32* %gep2, %ptr2
br i1 %cmp, label %loop.end, label %if2
if2:
br label %loop.end
loop.end:
%phi3 = phi i32* [ %gep2, %then ], [ %ptr1, %if2 ]
%val3 = load i32, i32* %gep2, align 4
store i32 %val3, i32* %phi3, align 4
%gep3 = getelementptr inbounds i32, i32* %ptr1, i32 1
br i1 undef, label %loop, label %if1
}
|