[llvm] r225290 - R600/SI: Insert s_waitcnt before s_barrier instructions.

[Tom Stellard]

Author: tstellar
Date: Tue Jan  6 13:52:07 2015
New Revision: 225290

URL: http://llvm.org/viewvc/llvm-project?rev=225290&view=rev
Log:
R600/SI: Insert s_waitcnt before s_barrier instructions.

This ensures that all memory operations are complete when all threads
reach the barrier.

Modified:
    llvm/trunk/lib/Target/R600/SIInsertWaits.cpp
    llvm/trunk/test/CodeGen/R600/llvm.AMDGPU.barrier.global.ll
    llvm/trunk/test/CodeGen/R600/llvm.AMDGPU.barrier.local.ll

Modified: llvm/trunk/lib/Target/R600/SIInsertWaits.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/R600/SIInsertWaits.cpp?rev=225290&r1=225289&r2=225290&view=diff
==============================================================================
--- llvm/trunk/lib/Target/R600/SIInsertWaits.cpp (original)
+++ llvm/trunk/lib/Target/R600/SIInsertWaits.cpp Tue Jan  6 13:52:07 2015
@@ -428,7 +428,11 @@ bool SIInsertWaits::runOnMachineFunction
     for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end();
          I != E; ++I) {
 
-      Changes |= insertWait(MBB, I, handleOperands(*I));
+      // Wait for everything before a barrier.
+      if (I->getOpcode() == AMDGPU::S_BARRIER)
+        Changes |= insertWait(MBB, I, LastIssued);
+      else
+        Changes |= insertWait(MBB, I, handleOperands(*I));
       pushInstruction(MBB, I);
     }
 

Modified: llvm/trunk/test/CodeGen/R600/llvm.AMDGPU.barrier.global.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/R600/llvm.AMDGPU.barrier.global.ll?rev=225290&r1=225289&r2=225290&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/R600/llvm.AMDGPU.barrier.global.ll (original)
+++ llvm/trunk/test/CodeGen/R600/llvm.AMDGPU.barrier.global.ll Tue Jan  6 13:52:07 2015
@@ -3,6 +3,8 @@
 
 ; FUNC-LABEL: {{^}}test_barrier_global:
 ; EG: GROUP_BARRIER
+; SI: buffer_store_dword
+; SI: s_waitcnt
 ; SI: s_barrier
 
 define void @test_barrier_global(i32 addrspace(1)* %out) {

Modified: llvm/trunk/test/CodeGen/R600/llvm.AMDGPU.barrier.local.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/R600/llvm.AMDGPU.barrier.local.ll?rev=225290&r1=225289&r2=225290&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/R600/llvm.AMDGPU.barrier.local.ll (original)
+++ llvm/trunk/test/CodeGen/R600/llvm.AMDGPU.barrier.local.ll Tue Jan  6 13:52:07 2015
@@ -3,6 +3,9 @@
 
 ; FUNC-LABEL: {{^}}test_barrier_local:
 ; EG: GROUP_BARRIER
+
+; SI: buffer_store_dword
+; SI: s_waitcnt
 ; SI: s_barrier
 
 define void @test_barrier_local(i32 addrspace(1)* %out) {