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| ; Tests to ensure that we are not placing backedge safepoints in
; loops which are clearly finite.
;; RUN: opt < %s -place-safepoints -spp-counted-loop-trip-width=32 -S | FileCheck %s
;; RUN: opt < %s -place-safepoints -spp-counted-loop-trip-width=64 -S | FileCheck %s -check-prefix=COUNTED-64
; A simple counted loop with trivially known range
define void @test1(i32) gc "statepoint-example" {
; CHECK-LABEL: test1
; CHECK-LABEL: entry
; CHECK: call void @do_safepoint
; CHECK-LABEL: loop
; CHECK-NOT: call void @do_safepoint
; CHECK-LABEL: exit
entry:
br label %loop
loop:
%counter = phi i32 [ 0 , %entry ], [ %counter.inc , %loop ]
%counter.inc = add i32 %counter, 1
%counter.cmp = icmp slt i32 %counter.inc, 16
br i1 %counter.cmp, label %loop, label %exit
exit:
ret void
}
; The same counted loop, but with an unknown early exit
define void @test2(i32) gc "statepoint-example" {
; CHECK-LABEL: test2
; CHECK-LABEL: entry
; CHECK: call void @do_safepoint
; CHECK-LABEL: loop
; CHECK-NOT: call void @do_safepoint
; CHECK-LABEL: exit
entry:
br label %loop
loop:
%counter = phi i32 [ 0 , %entry ], [ %counter.inc , %continue ]
%counter.inc = add i32 %counter, 1
%counter.cmp = icmp slt i32 %counter.inc, 16
br i1 undef, label %continue, label %exit
continue:
br i1 %counter.cmp, label %loop, label %exit
exit:
ret void
}
; The range is a 8 bit value and we can't overflow
define void @test3(i8 %upper) gc "statepoint-example" {
; CHECK-LABEL: test3
; CHECK-LABEL: entry
; CHECK: call void @do_safepoint
; CHECK-LABEL: loop
; CHECK-NOT: call void @do_safepoint
; CHECK-LABEL: exit
entry:
br label %loop
loop:
%counter = phi i8 [ 0 , %entry ], [ %counter.inc , %loop ]
%counter.inc = add nsw i8 %counter, 1
%counter.cmp = icmp slt i8 %counter.inc, %upper
br i1 %counter.cmp, label %loop, label %exit
exit:
ret void
}
; The range is a 64 bit value
define void @test4(i64 %upper) gc "statepoint-example" {
; CHECK-LABEL: test4
; CHECK-LABEL: entry
; CHECK: call void @do_safepoint
; CHECK-LABEL: loop
; CHECK: call void @do_safepoint
; CHECK-LABEL: exit
; COUNTED-64-LABEL: test4
; COUNTED-64-LABEL: entry
; COUNTED-64: call void @do_safepoint
; COUNTED-64-LABEL: loop
; COUNTED-64-NOT: call void @do_safepoint
; COUNTED-64-LABEL: exit
entry:
br label %loop
loop:
%counter = phi i64 [ 0 , %entry ], [ %counter.inc , %loop ]
%counter.inc = add i64 %counter, 1
%counter.cmp = icmp slt i64 %counter.inc, %upper
br i1 %counter.cmp, label %loop, label %exit
exit:
ret void
}
; This loop can run infinitely (for %upper == INT64_MAX) so it needs a
; safepoint.
define void @test5(i64 %upper) gc "statepoint-example" {
; CHECK-LABEL: test5
; CHECK-LABEL: entry
; CHECK: call void @do_safepoint
; CHECK-LABEL: loop
; CHECK: call void @do_safepoint
; CHECK-LABEL: exit
; COUNTED-64-LABEL: test5
; COUNTED-64-LABEL: entry
; COUNTED-64: call void @do_safepoint
; COUNTED-64-LABEL: loop
; COUNTED-64: call void @do_safepoint
; COUNTED-64-LABEL: exit
entry:
br label %loop
loop:
%counter = phi i64 [ 0 , %entry ], [ %counter.inc , %loop ]
%counter.inc = add i64 %counter, 1
%counter.cmp = icmp sle i64 %counter.inc, %upper
br i1 %counter.cmp, label %loop, label %exit
exit:
ret void
}
; This function is inlined when inserting a poll.
declare void @do_safepoint()
define void @gc.safepoint_poll() {
; CHECK-LABEL: gc.safepoint_poll
entry:
call void @do_safepoint()
ret void
} |