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; RUN: opt < %s -passes=simplifycfg -S | FileCheck %s
; Ensure branch weight does not overflow when folding block 3 into block 0.
; This IR test is reduced from an optimization that occurs during the Jump
; Threading pass, which creates a branch prediction of 0% and 100%. This is
; reduced in SimplifyCFG into the IR shown in the
; switch-branch-weight-overflow.ll test.
define void @foo(ptr %Overflow) {
; CHECK-LABEL: define void @foo
; CHECK: br i1 {{.*}}, label %[[BB2:.*]], label %[[BB3:.*]], !prof [[PROF0:![0-9]+]]
%1 = extractvalue { i32, i1 } zeroinitializer, 0
%2 = icmp eq i32 %1, 0
br i1 %2, label %6, label %3
3: ; preds = %0
%4 = icmp eq i32 %1, 1
br i1 %4, label %5, label %6, !prof !0
5: ; preds = %3
store i32 0, ptr %Overflow, align 4
br label %6
6: ; preds = %5, %3, %0
ret void
}
; Ensure that the branch weight from folding branch 0 and the default branch
; does not overflow. This IR test is reduced from the IR above.
define void @bar(ptr %Overflow) {
; CHECK-LABEL: define void @bar
; CHECK: br i1 {{.*}}, label %[[BB2:.*]], label %[[BB3:.*]], !prof [[PROF1:![0-9]+]]
%1 = extractvalue { i32, i1 } zeroinitializer, 0
switch i32 %1, label %3 [
i32 0, label %3
i32 1, label %2
], !prof !1
2: ; preds = %0
store i32 0, ptr %Overflow, align 4
br label %3
3: ; preds = %0, %0, %2
ret void
}
; CHECK: [[PROF0]] = !{!"branch_weights", i32 0, i32 -2147483648}
; CHECK: [[PROF1]] = !{!"branch_weights", i32 500, i32 -2147483648}
!0 = !{!"branch_weights", !"expected", i32 0, i32 -2147483648}
!1 = !{!"branch_weights", !"expected", i32 -2147483648, i32 -2147483648, i32 1000}
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