mirror of
https://github.com/RPCS3/llvm.git
synced 2024-12-21 03:28:31 +00:00
d0dbe02fd2
The C and C++ semantics for compare_exchange require it to return a bool
indicating success. This gets mapped to LLVM IR which follows each cmpxchg with
an icmp of the value loaded against the desired value.
When lowered to ldxr/stxr loops, this extra comparison is redundant: its
results are implicit in the control-flow of the function.
This commit makes two changes: it replaces that icmp with appropriate PHI
nodes, and then makes sure earlyCSE is called after expansion to actually make
use of the opportunities revealed.
I've also added -{arm,aarch64}-enable-atomic-tidy options, so that
existing fragile tests aren't perturbed too much by the change. Many
of them either rely on undef/unreachable too pervasively to be
restored to something well-defined (particularly while making sure
they test the same obscure assert from many years ago), or depend on a
particular CFG shape, which is disrupted by SimplifyCFG.
rdar://problem/16227836
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209883 91177308-0d34-0410-b5e6-96231b3b80d8
28 lines
1.1 KiB
LLVM
28 lines
1.1 KiB
LLVM
; RUN: llc -mtriple=aarch64-none-linux-gnu -aarch64-atomic-cfg-tidy=0 -verify-machineinstrs < %s | FileCheck %s
|
|
; RUN: llc -code-model=large -mtriple=aarch64-none-linux-gnu -aarch64-atomic-cfg-tidy=0 -verify-machineinstrs < %s | FileCheck --check-prefix=CHECK-LARGE %s
|
|
|
|
@addr = global i8* null
|
|
|
|
define void @test_blockaddress() {
|
|
; CHECK-LABEL: test_blockaddress:
|
|
store volatile i8* blockaddress(@test_blockaddress, %block), i8** @addr
|
|
%val = load volatile i8** @addr
|
|
indirectbr i8* %val, [label %block]
|
|
; CHECK: adrp [[DEST_HI:x[0-9]+]], [[DEST_LBL:.Ltmp[0-9]+]]
|
|
; CHECK: add [[DEST:x[0-9]+]], [[DEST_HI]], {{#?}}:lo12:[[DEST_LBL]]
|
|
; CHECK: str [[DEST]],
|
|
; CHECK: ldr [[NEWDEST:x[0-9]+]]
|
|
; CHECK: br [[NEWDEST]]
|
|
|
|
; CHECK-LARGE: movz [[ADDR_REG:x[0-9]+]], #:abs_g3:[[DEST_LBL:.Ltmp[0-9]+]]
|
|
; CHECK-LARGE: movk [[ADDR_REG]], #:abs_g2_nc:[[DEST_LBL]]
|
|
; CHECK-LARGE: movk [[ADDR_REG]], #:abs_g1_nc:[[DEST_LBL]]
|
|
; CHECK-LARGE: movk [[ADDR_REG]], #:abs_g0_nc:[[DEST_LBL]]
|
|
; CHECK-LARGE: str [[ADDR_REG]],
|
|
; CHECK-LARGE: ldr [[NEWDEST:x[0-9]+]]
|
|
; CHECK-LARGE: br [[NEWDEST]]
|
|
|
|
block:
|
|
ret void
|
|
}
|