llvm-6502/test/Transforms/RewriteStatepointsForGC/base-pointers-7.ll
Pat Gavlin 5c7f7462e4 Extend the statepoint intrinsic to allow statepoints to be marked as transitions from GC-aware code to code that is not GC-aware.
This changes the shape of the statepoint intrinsic from:

  @llvm.experimental.gc.statepoint(anyptr target, i32 # call args, i32 unused, ...call args, i32 # deopt args, ...deopt args, ...gc args)

to:

  @llvm.experimental.gc.statepoint(anyptr target, i32 # call args, i32 flags, ...call args, i32 # transition args, ...transition args, i32 # deopt args, ...deopt args, ...gc args)

This extension offers the backend the opportunity to insert (somewhat) arbitrary code to manage the transition from GC-aware code to code that is not GC-aware and back.

In order to support the injection of transition code, this extension wraps the STATEPOINT ISD node generated by the usual lowering lowering with two additional nodes: GC_TRANSITION_START and GC_TRANSITION_END. The transition arguments that were passed passed to the intrinsic (if any) are lowered and provided as operands to these nodes and may be used by the backend during code generation.

Eventually, the lowering of the GC_TRANSITION_{START,END} nodes should be informed by the GC strategy in use for the function containing the intrinsic call; for now, these nodes are instead replaced with no-ops.

Differential Revision: http://reviews.llvm.org/D9501

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236888 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-08 18:07:42 +00:00

54 lines
1.7 KiB
LLVM

; RUN: opt %s -rewrite-statepoints-for-gc -spp-print-base-pointers -S 2>&1 | FileCheck %s
; CHECK: derived %merged_value base %base_phi
declare void @site_for_call_safpeoint()
define i64 addrspace(1)* @test(i64 addrspace(1)* %base_obj_x,
i64 addrspace(1)* %base_obj_y, i1 %runtime_condition_x,
i1 %runtime_condition_y) gc "statepoint-example" {
entry:
br i1 %runtime_condition_x, label %here, label %there
here:
br i1 %runtime_condition_y, label %bump_here_a, label %bump_here_b
bump_here_a:
%x_a = getelementptr i64, i64 addrspace(1)* %base_obj_x, i32 1
br label %merge_here
bump_here_b:
%x_b = getelementptr i64, i64 addrspace(1)* %base_obj_y, i32 2
br label %merge_here
merge_here:
; CHECK: merge_here:
; CHECK-DAG: %base_phi
; CHECK-DAG: phi i64 addrspace(1)*
; CHECK-DAG: [ %base_obj_x, %bump_here_a ]
; CHECK-DAG: [ %base_obj_y, %bump_here_b ]
%x = phi i64 addrspace(1)* [ %x_a , %bump_here_a ], [ %x_b , %bump_here_b ]
br label %merge
there:
%y = getelementptr i64, i64 addrspace(1)* %base_obj_y, i32 1
br label %merge
merge:
; CHECK: merge:
; CHECK-DAG: %base_phi1
; CHECK-DAG: phi i64 addrspace(1)*
; CHECK-DAG: %merge_here
; CHECK-DAG: [ %base_obj_y, %there ]
; CHECK: %merged_value = phi i64 addrspace(1)* [ %x, %merge_here ], [ %y, %there ]
%merged_value = phi i64 addrspace(1)* [ %x, %merge_here ], [ %y, %there ]
%safepoint_token = call i32 (void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()* @site_for_call_safpeoint, i32 0, i32 0, i32 0, i32 5, i32 0, i32 -1, i32 0, i32 0, i32 0)
ret i64 addrspace(1)* %merged_value
}
declare void @do_safepoint()
declare i32 @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()*, i32, i32, ...)