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

1 files changed, 18 insertions, 8 deletions

diff --git a/llvm/test/Assembler/atomic.ll b/llvm/test/Assembler/atomic.ll
index 148b95d88e3..a8b527f2f86 100644
--- a/llvm/test/Assembler/atomic.ll
+++ b/llvm/test/Assembler/atomic.ll
@@ -5,14 +5,20 @@
 define void @f(i32* %x) {
   ; CHECK: load atomic i32, i32* %x unordered, align 4
   load atomic i32, i32* %x unordered, align 4
-  ; CHECK: load atomic volatile i32, i32* %x singlethread acquire, align 4
-  load atomic volatile i32, i32* %x singlethread acquire, align 4
+  ; CHECK: load atomic volatile i32, i32* %x syncscope("singlethread") acquire, align 4
+  load atomic volatile i32, i32* %x syncscope("singlethread") acquire, align 4
+  ; CHECK: load atomic volatile i32, i32* %x syncscope("agent") acquire, align 4
+  load atomic volatile i32, i32* %x syncscope("agent") acquire, align 4
   ; CHECK: store atomic i32 3, i32* %x release, align 4
   store atomic i32 3, i32* %x release, align 4
-  ; CHECK: store atomic volatile i32 3, i32* %x singlethread monotonic, align 4
-  store atomic volatile i32 3, i32* %x singlethread monotonic, align 4
-  ; CHECK: cmpxchg i32* %x, i32 1, i32 0 singlethread monotonic monotonic
-  cmpxchg i32* %x, i32 1, i32 0 singlethread monotonic monotonic
+  ; CHECK: store atomic volatile i32 3, i32* %x syncscope("singlethread") monotonic, align 4
+  store atomic volatile i32 3, i32* %x syncscope("singlethread") monotonic, align 4
+  ; CHECK: store atomic volatile i32 3, i32* %x syncscope("workgroup") monotonic, align 4
+  store atomic volatile i32 3, i32* %x syncscope("workgroup") monotonic, align 4
+  ; CHECK: cmpxchg i32* %x, i32 1, i32 0 syncscope("singlethread") monotonic monotonic
+  cmpxchg i32* %x, i32 1, i32 0 syncscope("singlethread") monotonic monotonic
+  ; CHECK: cmpxchg i32* %x, i32 1, i32 0 syncscope("workitem") monotonic monotonic
+  cmpxchg i32* %x, i32 1, i32 0 syncscope("workitem") monotonic monotonic
   ; CHECK: cmpxchg volatile i32* %x, i32 0, i32 1 acq_rel acquire
   cmpxchg volatile i32* %x, i32 0, i32 1 acq_rel acquire
   ; CHECK: cmpxchg i32* %x, i32 42, i32 0 acq_rel monotonic
@@ -23,9 +29,13 @@ define void @f(i32* %x) {
   atomicrmw add i32* %x, i32 10 seq_cst
   ; CHECK: atomicrmw volatile xchg  i32* %x, i32 10 monotonic
   atomicrmw volatile xchg i32* %x, i32 10 monotonic
-  ; CHECK: fence singlethread release
-  fence singlethread release
+  ; CHECK: atomicrmw volatile xchg  i32* %x, i32 10 syncscope("agent") monotonic
+  atomicrmw volatile xchg i32* %x, i32 10 syncscope("agent") monotonic
+  ; CHECK: fence syncscope("singlethread") release
+  fence syncscope("singlethread") release
   ; CHECK: fence seq_cst
   fence seq_cst
+  ; CHECK: fence syncscope("device") seq_cst
+  fence syncscope("device") seq_cst
   ret void
 }