mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-10-21 20:12:56 +02:00
6d67db8c09
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 llvm-svn: 237214
107 lines
5.0 KiB
LLVM
107 lines
5.0 KiB
LLVM
; RUN: opt -O3 -S < %s | FileCheck --check-prefix=CHECK-OPT %s
|
|
; RUN: llc < %s | FileCheck --check-prefix=CHECK-LLC %s
|
|
; These tests are targetted at making sure we don't retain information
|
|
; about memory which contains potential gc references across a statepoint.
|
|
; They're carefully written to only outlaw forwarding of references.
|
|
; Depending on the collector, forwarding non-reference fields or
|
|
; constant null references may be perfectly legal. (If unimplemented.)
|
|
; The general structure of these tests is:
|
|
; - learn a fact about memory (via an assume)
|
|
; - cross a statepoint
|
|
; - check the same fact about memory (which we no longer know)
|
|
|
|
target datalayout = "e-i64:64-f80:128-n8:16:32:64-S128"
|
|
target triple = "x86_64-pc-linux-gnu"
|
|
|
|
; If not at a statepoint, we could forward known memory values
|
|
; across this call.
|
|
declare void @func() readonly
|
|
|
|
;; Forwarding the value of a pointer load is invalid since it may have
|
|
;; changed at the safepoint. Forwarding a non-gc pointer value would
|
|
;; be valid, but is not currently implemented.
|
|
define i1 @test_load_forward(i32 addrspace(1)* addrspace(1)* %p) gc "statepoint-example" {
|
|
entry:
|
|
%before = load i32 addrspace(1)*, i32 addrspace(1)* addrspace(1)* %p
|
|
%cmp1 = call i1 @f(i32 addrspace(1)* %before)
|
|
call void @llvm.assume(i1 %cmp1)
|
|
%safepoint_token = tail call i32 (i64, i32, void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(i64 0, i32 0, void ()* @func, i32 0, i32 0, i32 0, i32 0, i32 addrspace(1)* addrspace(1)* %p)
|
|
%pnew = call i32 addrspace(1)* addrspace(1)* @llvm.experimental.gc.relocate.p1p1i32(i32 %safepoint_token, i32 7, i32 7)
|
|
%after = load i32 addrspace(1)*, i32 addrspace(1)* addrspace(1)* %pnew
|
|
%cmp2 = call i1 @f(i32 addrspace(1)* %after)
|
|
ret i1 %cmp2
|
|
|
|
; CHECK-OPT-LABEL: test_load_forward
|
|
; CHECK-OPT: ret i1 %cmp2
|
|
; CHECK-LLC-LABEL: test_load_forward
|
|
; CHECK-LLC: callq f
|
|
}
|
|
|
|
;; Same as above, but forwarding from a store
|
|
define i1 @test_store_forward(i32 addrspace(1)* addrspace(1)* %p,
|
|
i32 addrspace(1)* %v) gc "statepoint-example" {
|
|
entry:
|
|
%cmp1 = call i1 @f(i32 addrspace(1)* %v)
|
|
call void @llvm.assume(i1 %cmp1)
|
|
store i32 addrspace(1)* %v, i32 addrspace(1)* addrspace(1)* %p
|
|
%safepoint_token = tail call i32 (i64, i32, void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(i64 0, i32 0, void ()* @func, i32 0, i32 0, i32 0, i32 0, i32 addrspace(1)* addrspace(1)* %p)
|
|
%pnew = call i32 addrspace(1)* addrspace(1)* @llvm.experimental.gc.relocate.p1p1i32(i32 %safepoint_token, i32 7, i32 7)
|
|
%after = load i32 addrspace(1)*, i32 addrspace(1)* addrspace(1)* %pnew
|
|
%cmp2 = call i1 @f(i32 addrspace(1)* %after)
|
|
ret i1 %cmp2
|
|
|
|
; CHECK-OPT-LABEL: test_store_forward
|
|
; CHECK-OPT: ret i1 %cmp2
|
|
; CHECK-LLC-LABEL: test_store_forward
|
|
; CHECK-LLC: callq f
|
|
}
|
|
|
|
; A predicate on the pointer which is not simply null, but whose value
|
|
; would be known unchanged if the pointer value could be forwarded.
|
|
; The implementation of such a function could inspect the integral value
|
|
; of the pointer and is thus not safe to reuse after a statepoint.
|
|
declare i1 @f(i32 addrspace(1)* %v) readnone
|
|
|
|
; This is a variant of the test_load_forward test which is intended to
|
|
; highlight the fact that a gc pointer can be stored in part of the heap
|
|
; that is not itself GC managed. The GC may have an external mechanism
|
|
; to know about and update that value at a safepoint. Note that the
|
|
; statepoint does not provide the collector with this root.
|
|
define i1 @test_load_forward_nongc_heap(i32 addrspace(1)** %p) gc "statepoint-example" {
|
|
entry:
|
|
%before = load i32 addrspace(1)*, i32 addrspace(1)** %p
|
|
%cmp1 = call i1 @f(i32 addrspace(1)* %before)
|
|
call void @llvm.assume(i1 %cmp1)
|
|
call i32 (i64, i32, void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(i64 0, i32 0, void ()* @func, i32 0, i32 0, i32 0, i32 0)
|
|
%after = load i32 addrspace(1)*, i32 addrspace(1)** %p
|
|
%cmp2 = call i1 @f(i32 addrspace(1)* %after)
|
|
ret i1 %cmp2
|
|
|
|
; CHECK-OPT-LABEL: test_load_forward_nongc_heap
|
|
; CHECK-OPT: ret i1 %cmp2
|
|
; CHECK-LLC-LABEL: test_load_forward_nongc_heap
|
|
; CHECK-LLC: callq f
|
|
}
|
|
|
|
;; Same as above, but forwarding from a store
|
|
define i1 @test_store_forward_nongc_heap(i32 addrspace(1)** %p,
|
|
i32 addrspace(1)* %v) gc "statepoint-example" {
|
|
entry:
|
|
%cmp1 = call i1 @f(i32 addrspace(1)* %v)
|
|
call void @llvm.assume(i1 %cmp1)
|
|
store i32 addrspace(1)* %v, i32 addrspace(1)** %p
|
|
call i32 (i64, i32, void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(i64 0, i32 0, void ()* @func, i32 0, i32 0, i32 0, i32 0)
|
|
%after = load i32 addrspace(1)*, i32 addrspace(1)** %p
|
|
%cmp2 = call i1 @f(i32 addrspace(1)* %after)
|
|
ret i1 %cmp2
|
|
|
|
; CHECK-OPT-LABEL: test_store_forward_nongc_heap
|
|
; CHECK-OPT: ret i1 %cmp2
|
|
; CHECK-LLC-LABEL: test_store_forward_nongc_heap
|
|
; CHECK-LLC: callq f
|
|
}
|
|
|
|
declare void @llvm.assume(i1)
|
|
declare i32 @llvm.experimental.gc.statepoint.p0f_isVoidf(i64, i32, void ()*, i32, i32, ...)
|
|
declare i32 addrspace(1)* addrspace(1)* @llvm.experimental.gc.relocate.p1p1i32(i32, i32, i32) #3
|