From 7740daa8ba053294b7448556c049cf6778711d66 Mon Sep 17 00:00:00 2001
From: Michel Danzer <michel.daenzer@amd.com>
Date: Wed, 10 Jul 2013 16:36:43 +0000
Subject: [PATCH] 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
---
 lib/Target/R600/SIInsertWaits.cpp      |  2 ++
 lib/Target/R600/SIInstrFormats.td      | 24 ++++++++++++++++++++++++
 lib/Target/R600/SIInstrInfo.td         | 23 +++++++++++++++++++++++
 lib/Target/R600/SIInstructions.td      |  3 +++
 lib/Target/R600/SILowerControlFlow.cpp | 16 ++++++++++++++++
 5 files changed, 68 insertions(+)

diff --git a/lib/Target/R600/SIInsertWaits.cpp b/lib/Target/R600/SIInsertWaits.cpp
index c36e1dc3041..d31da4585ff 100644
--- a/lib/Target/R600/SIInsertWaits.cpp
+++ b/lib/Target/R600/SIInsertWaits.cpp
@@ -134,6 +134,8 @@ Counters SIInsertWaits::getHwCounts(MachineInstr &MI) {
   if (TSFlags & SIInstrFlags::LGKM_CNT) {
 
     MachineOperand &Op = MI.getOperand(0);
+    if (!Op.isReg())
+      Op = MI.getOperand(1);
     assert(Op.isReg() && "First LGKM operand must be a register!");
 
     unsigned Reg = Op.getReg();
diff --git a/lib/Target/R600/SIInstrFormats.td b/lib/Target/R600/SIInstrFormats.td
index 51f323d88ae..434aa7e0bf0 100644
--- a/lib/Target/R600/SIInstrFormats.td
+++ b/lib/Target/R600/SIInstrFormats.td
@@ -281,6 +281,30 @@ class VINTRP <bits <2> op, dag outs, dag ins, string asm, list<dag> pattern> :
 
 let Uses = [EXEC] in {
 
+class DS <bits<8> op, dag outs, dag ins, string asm, list<dag> pattern> :
+    Enc64 <outs, ins, asm, pattern> {
+
+  bits<8> vdst;
+  bits<1> gds;
+  bits<8> addr;
+  bits<8> data0;
+  bits<8> data1;
+  bits<8> offset0;
+  bits<8> offset1;
+
+  let Inst{7-0} = offset0;
+  let Inst{15-8} = offset1;
+  let Inst{17} = gds;
+  let Inst{25-18} = op;
+  let Inst{31-26} = 0x36; //encoding
+  let Inst{39-32} = addr;
+  let Inst{47-40} = data0;
+  let Inst{55-48} = data1;
+  let Inst{63-56} = vdst;
+
+  let LGKM_CNT = 1;
+}
+
 class MUBUF <bits<7> op, dag outs, dag ins, string asm, list<dag> pattern> :
     Enc64<outs, ins, asm, pattern> {
 
diff --git a/lib/Target/R600/SIInstrInfo.td b/lib/Target/R600/SIInstrInfo.td
index 36812caa75b..655a8b1641a 100644
--- a/lib/Target/R600/SIInstrInfo.td
+++ b/lib/Target/R600/SIInstrInfo.td
@@ -287,6 +287,29 @@ class VOP3_64 <bits<9> op, string opName, list<dag> pattern> : VOP3 <
 // Vector I/O classes
 //===----------------------------------------------------------------------===//
 
+class DS_Load_Helper <bits<8> op, string asm, RegisterClass regClass> : DS <
+  op,
+  (outs regClass:$vdst),
+  (ins i1imm:$gds, VReg_32:$addr, VReg_32:$data0, VReg_32:$data1,
+       i8imm:$offset0, i8imm:$offset1),
+  asm#" $vdst, $gds, $addr, $data0, $data1, $offset0, $offset1, [M0]",
+  []> {
+  let mayLoad = 1;
+  let mayStore = 0;
+}
+
+class DS_Store_Helper <bits<8> op, string asm, RegisterClass regClass> : DS <
+  op,
+  (outs),
+  (ins i1imm:$gds, VReg_32:$addr, VReg_32:$data0, VReg_32:$data1,
+       i8imm:$offset0, i8imm:$offset1),
+  asm#" $gds, $addr, $data0, $data1, $offset0, $offset1, [M0]",
+  []> {
+  let mayStore = 1;
+  let mayLoad = 0;
+  let vdst = 0;
+}
+
 class MTBUF_Store_Helper <bits<3> op, string asm, RegisterClass regClass> : MTBUF <
   op,
   (outs),
diff --git a/lib/Target/R600/SIInstructions.td b/lib/Target/R600/SIInstructions.td
index c9eac7d885f..09460d83a3f 100644
--- a/lib/Target/R600/SIInstructions.td
+++ b/lib/Target/R600/SIInstructions.td
@@ -391,6 +391,9 @@ defm V_CMPX_CLASS_F64 : VOPC_64 <0x000000b8, "V_CMPX_CLASS_F64">;
 
 } // End isCompare = 1
 
+def DS_WRITE_B32 : DS_Store_Helper <0x0000000d, "DS_WRITE_B32", VReg_32>;
+def DS_READ_B32 : DS_Load_Helper <0x00000036, "DS_READ_B32", VReg_32>;
+
 //def BUFFER_LOAD_FORMAT_X : MUBUF_ <0x00000000, "BUFFER_LOAD_FORMAT_X", []>;
 //def BUFFER_LOAD_FORMAT_XY : MUBUF_ <0x00000001, "BUFFER_LOAD_FORMAT_XY", []>;
 //def BUFFER_LOAD_FORMAT_XYZ : MUBUF_ <0x00000002, "BUFFER_LOAD_FORMAT_XYZ", []>;
diff --git a/lib/Target/R600/SILowerControlFlow.cpp b/lib/Target/R600/SILowerControlFlow.cpp
index 5b434fb3825..c2e8f024e78 100644
--- a/lib/Target/R600/SILowerControlFlow.cpp
+++ b/lib/Target/R600/SILowerControlFlow.cpp
@@ -411,6 +411,7 @@ bool SILowerControlFlowPass::runOnMachineFunction(MachineFunction &MF) {
   TRI = MF.getTarget().getRegisterInfo();
 
   bool HaveKill = false;
+  bool NeedM0 = false;
   bool NeedWQM = false;
   unsigned Depth = 0;
 
@@ -482,6 +483,13 @@ bool SILowerControlFlowPass::runOnMachineFunction(MachineFunction &MF) {
           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 @@ bool SILowerControlFlowPass::runOnMachineFunction(MachineFunction &MF) {
     }
   }
 
+  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),