R600/SI: Initial support for LDS/GDS instructions
Reviewed-by: Tom Stellard <thomas.stellard@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186009 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/R600/SILowerControlFlow.cpp b/lib/Target/R600/SILowerControlFlow.cpp
index 5b434fb..c2e8f02 100644
--- a/lib/Target/R600/SILowerControlFlow.cpp
+++ b/lib/Target/R600/SILowerControlFlow.cpp
@@ -411,6 +411,7 @@
TRI = MF.getTarget().getRegisterInfo();
bool HaveKill = false;
+ bool NeedM0 = false;
bool NeedWQM = false;
unsigned Depth = 0;
@@ -482,6 +483,13 @@
IndirectDst(MI);
break;
+ case AMDGPU::DS_READ_B32:
+ NeedWQM = true;
+ // Fall through
+ case AMDGPU::DS_WRITE_B32:
+ NeedM0 = true;
+ break;
+
case AMDGPU::V_INTERP_P1_F32:
case AMDGPU::V_INTERP_P2_F32:
case AMDGPU::V_INTERP_MOV_F32:
@@ -492,6 +500,14 @@
}
}
+ if (NeedM0) {
+ MachineBasicBlock &MBB = MF.front();
+ // Initialize M0 to a value that won't cause LDS access to be discarded
+ // due to offset clamping
+ BuildMI(MBB, MBB.getFirstNonPHI(), DebugLoc(), TII->get(AMDGPU::S_MOV_B32),
+ AMDGPU::M0).addImm(0xffffffff);
+ }
+
if (NeedWQM) {
MachineBasicBlock &MBB = MF.front();
BuildMI(MBB, MBB.getFirstNonPHI(), DebugLoc(), TII->get(AMDGPU::S_WQM_B64),