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; RUN: opt -analyze -print-mustexecute %s
; CHECK: Printing analysis 'Instructions which execute on loop entry' for function 'header_with_icf':
; CHECK: The following are guaranteed to execute (for the respective loops):
; CHECK: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop ] (mustexec in: loop)
; CHECK: %v = load i32, i32* %p (mustexec in: loop)
; CHECK: call void @maythrow_and_use(i32 %v) (mustexec in: loop)
; CHECK-NOT: add
define i1 @header_with_icf(i32* noalias %p, i32 %high) {
entry:
br label %loop
loop:
%iv = phi i32 [0, %entry], [%iv.next, %loop]
%v = load i32, i32* %p
call void @maythrow_and_use(i32 %v)
%iv.next = add nsw nuw i32 %iv, 1
%exit.test = icmp slt i32 %iv, %high
br i1 %exit.test, label %exit, label %loop
exit:
ret i1 false
}
; CHECK: Printing analysis 'Instructions which execute on loop entry' for function 'test':
; CHECK: The following are guaranteed to execute (for the respective loops):
; CHECK: %iv = phi i32 [ 0, %entry ], [ %iv.next, %next ] (mustexec in: loop)
; CHECK: %v = load i32, i32* %p (mustexec in: loop)
; CHECK: br label %next (mustexec in: loop)
define i1 @test(i32* noalias %p, i32 %high) {
entry:
br label %loop
loop:
%iv = phi i32 [0, %entry], [%iv.next, %next]
%v = load i32, i32* %p
br label %next
next:
call void @maythrow_and_use(i32 %v)
%iv.next = add nsw nuw i32 %iv, 1
%exit.test = icmp slt i32 %iv, %high
br i1 %exit.test, label %exit, label %loop
exit:
ret i1 false
}
; CHECK: Printing analysis 'Instructions which execute on loop entry' for function 'nested':
; CHECK: The following are guaranteed to execute (for the respective loops):
; CHECK: %iv = phi i32 [ 0, %entry ], [ %iv.next, %next ] (mustexec in: loop)
; CHECK: br label %inner_loop (mustexec in: loop)
; FIXME: These three are also must execute for the outer loop.
; CHECK: %v = load i32, i32* %p (mustexec in: inner_loop)
; CHECK: %inner.test = icmp eq i32 %v, 0 (mustexec in: inner_loop)
; CHECK: br i1 %inner.test, label %inner_loop, label %next (mustexec in: inner_loop)
define i1 @nested(i32* noalias %p, i32 %high) {
entry:
br label %loop
loop:
%iv = phi i32 [0, %entry], [%iv.next, %next]
br label %inner_loop
inner_loop:
%v = load i32, i32* %p
%inner.test = icmp eq i32 %v, 0
br i1 %inner.test, label %inner_loop, label %next
next:
call void @maythrow_and_use(i32 %v)
%iv.next = add nsw nuw i32 %iv, 1
%exit.test = icmp slt i32 %iv, %high
br i1 %exit.test, label %exit, label %loop
exit:
ret i1 false
}
declare void @maythrow_and_use(i32)
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