llvm-mirror/test/Bitcode/atomic.ll
Konstantin Zhuravlyov d382d6f3fc Enhance synchscope representation
OpenCL 2.0 introduces the notion of memory scopes in atomic operations to
  global and local memory. These scopes restrict how synchronization is
  achieved, which can result in improved performance.

  This change extends existing notion of synchronization scopes in LLVM to
  support arbitrary scopes expressed as target-specific strings, in addition to
  the already defined scopes (single thread, system).

  The LLVM IR and MIR syntax for expressing synchronization scopes has changed
  to use *syncscope("<scope>")*, where <scope> can be "singlethread" (this
  replaces *singlethread* keyword), or a target-specific name. As before, if
  the scope is not specified, it defaults to CrossThread/System scope.

  Implementation details:
    - Mapping from synchronization scope name/string to synchronization scope id
      is stored in LLVM context;
    - CrossThread/System and SingleThread scopes are pre-defined to efficiently
      check for known scopes without comparing strings;
    - Synchronization scope names are stored in SYNC_SCOPE_NAMES_BLOCK in
      the bitcode.

Differential Revision: https://reviews.llvm.org/D21723

llvm-svn: 307722
2017-07-11 22:23:00 +00:00

19 lines
803 B
LLVM

; RUN: llvm-as %s -o - | llvm-dis | FileCheck %s
; RUN: verify-uselistorder < %s
define void @test_cmpxchg(i32* %addr, i32 %desired, i32 %new) {
cmpxchg i32* %addr, i32 %desired, i32 %new seq_cst seq_cst
; CHECK: cmpxchg i32* %addr, i32 %desired, i32 %new seq_cst seq_cst
cmpxchg volatile i32* %addr, i32 %desired, i32 %new seq_cst monotonic
; CHECK: cmpxchg volatile i32* %addr, i32 %desired, i32 %new seq_cst monotonic
cmpxchg weak i32* %addr, i32 %desired, i32 %new acq_rel acquire
; CHECK: cmpxchg weak i32* %addr, i32 %desired, i32 %new acq_rel acquire
cmpxchg weak volatile i32* %addr, i32 %desired, i32 %new syncscope("singlethread") release monotonic
; CHECK: cmpxchg weak volatile i32* %addr, i32 %desired, i32 %new syncscope("singlethread") release monotonic
ret void
}