llvm-6502/test/Transforms/PlaceSafepoints/basic.ll
Sanjoy Das ead2d1fbe0 [Statepoints] Support for "patchable" statepoints.
Summary:
This change adds two new parameters to the statepoint intrinsic, `i64 id`
and `i32 num_patch_bytes`.  `id` gets propagated to the ID field
in the generated StackMap section.  If the `num_patch_bytes` is
non-zero then the statepoint is lowered to `num_patch_bytes` bytes of
nops instead of a call (the spill and reload code remains unchanged).
A non-zero `num_patch_bytes` is useful in situations where a language
runtime requires complete control over how a call is lowered.

This change brings statepoints one step closer to patchpoints.  With
some additional work (that is not part of this patch) it should be
possible to get rid of `TargetOpcode::STATEPOINT` altogether.

PlaceSafepoints generates `statepoint` wrappers with `id` set to
`0xABCDEF00` (the old default value for the ID reported in the stackmap)
and `num_patch_bytes` set to `0`.  This can be made more sophisticated
later.

Reviewers: reames, pgavlin, swaroop.sridhar, AndyAyers

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9546

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237214 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-12 23:52:24 +00:00

95 lines
2.2 KiB
LLVM

; RUN: opt %s -S -place-safepoints | FileCheck %s
; Do we insert a simple entry safepoint?
define void @test_entry() gc "statepoint-example" {
; CHECK-LABEL: @test_entry
entry:
; CHECK-LABEL: entry
; CHECK: statepoint
ret void
}
; On a non-gc function, we should NOT get an entry safepoint
define void @test_negative() {
; CHECK-LABEL: @test_negative
entry:
; CHECK-NOT: statepoint
ret void
}
; Do we insert a backedge safepoint in a statically
; infinite loop?
define void @test_backedge() gc "statepoint-example" {
; CHECK-LABEL: test_backedge
entry:
; CHECK-LABEL: entry
; This statepoint is technically not required, but we don't exploit that yet.
; CHECK: statepoint
br label %other
; CHECK-LABEL: other
; CHECK: statepoint
other:
call void undef()
br label %other
}
; Check that we remove an unreachable block rather than trying
; to insert a backedge safepoint
define void @test_unreachable() gc "statepoint-example" {
; CHECK-LABEL: test_unreachable
entry:
; CHECK-LABEL: entry
; CHECK: statepoint
ret void
; CHECK-NOT: other
; CHECK-NOT: statepoint
other:
br label %other
}
declare void @foo()
; Do we turn a call into it's own statepoint
define void @test_simple_call() gc "statepoint-example" {
; CHECK-LABEL: test_simple_call
entry:
br label %other
other:
; CHECK-LABEL: other
; CHECK: statepoint
; CHECK-NOT: gc.result
call void @foo()
ret void
}
declare zeroext i1 @i1_return_i1(i1)
define i1 @test_call_with_result() gc "statepoint-example" {
; CHECK-LABEL: test_call_with_result
; This is checking that a statepoint_poll + statepoint + result is
; inserted for a function that takes 1 argument.
; CHECK: gc.statepoint.p0f_isVoidf
; CHECK: gc.statepoint.p0f_i1i1f
; CHECK: (i64 2882400000, i32 0, i1 (i1)* @i1_return_i1, i32 1, i32 0, i1 false, i32 0, i32 0)
; CHECK: %call1.2 = call i1 @llvm.experimental.gc.result.i1
entry:
%call1 = tail call i1 (i1) @i1_return_i1(i1 false)
ret i1 %call1
}
; This function is inlined when inserting a poll. To avoid recursive
; issues, make sure we don't place safepoints in it.
declare void @do_safepoint()
define void @gc.safepoint_poll() {
; CHECK-LABEL: gc.safepoint_poll
; CHECK-LABEL: entry
; CHECK-NEXT: do_safepoint
; CHECK-NEXT: ret void
entry:
call void @do_safepoint()
ret void
}