[AMDGPU][GFX10] Disabled v_movrel*[sdwa|dpp] opcodes in codegen

These opcodes use indirect register addressing so they need special handling by codegen (currently missing).

Reviewers: vpykhtin, arsenm, rampitec

Differential Revision: https://reviews.llvm.org/D70400

2 files changed, 27 insertions, 0 deletions

diff --git a/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp b/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
index 3737d0a7b41..ed915f03be2 100644
--- a/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
+++ b/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
@@ -6329,6 +6329,26 @@ static SIEncodingFamily subtargetEncodingFamily(const GCNSubtarget &ST) {
   llvm_unreachable("Unknown subtarget generation!");
 }
 
+bool SIInstrInfo::isAsmOnlyOpcode(int MCOp) const {
+  switch(MCOp) {
+  // These opcodes use indirect register addressing so
+  // they need special handling by codegen (currently missing).
+  // Therefore it is too risky to allow these opcodes
+  // to be selected by dpp combiner or sdwa peepholer.
+  case AMDGPU::V_MOVRELS_B32_dpp_gfx10:
+  case AMDGPU::V_MOVRELS_B32_sdwa_gfx10:
+  case AMDGPU::V_MOVRELD_B32_dpp_gfx10:
+  case AMDGPU::V_MOVRELD_B32_sdwa_gfx10:
+  case AMDGPU::V_MOVRELSD_B32_dpp_gfx10:
+  case AMDGPU::V_MOVRELSD_B32_sdwa_gfx10:
+  case AMDGPU::V_MOVRELSD_2_B32_dpp_gfx10:
+  case AMDGPU::V_MOVRELSD_2_B32_sdwa_gfx10:
+    return true;
+  default:
+    return false;
+  }
+}
+
 int SIInstrInfo::pseudoToMCOpcode(int Opcode) const {
   SIEncodingFamily Gen = subtargetEncodingFamily(ST);
 
@@ -6367,6 +6387,9 @@ int SIInstrInfo::pseudoToMCOpcode(int Opcode) const {
   if (MCOp == (uint16_t)-1)
     return -1;
 
+  if (isAsmOnlyOpcode(MCOp))
+    return -1;
+
   return MCOp;
 }
 
diff --git a/llvm/lib/Target/AMDGPU/SIInstrInfo.h b/llvm/lib/Target/AMDGPU/SIInstrInfo.h
index 821215d08f4..492bf4e4e92 100644
--- a/llvm/lib/Target/AMDGPU/SIInstrInfo.h
+++ b/llvm/lib/Target/AMDGPU/SIInstrInfo.h
@@ -1017,6 +1017,10 @@ public:
   /// not exist. If Opcode is not a pseudo instruction, this is identity.
   int pseudoToMCOpcode(int Opcode) const;
 
+  /// \brief Check if this instruction should only be used by assembler.
+  /// Return true if this opcode should not be used by codegen.
+  bool isAsmOnlyOpcode(int MCOp) const;
+
   const TargetRegisterClass *getRegClass(const MCInstrDesc &TID, unsigned OpNum,
                                          const TargetRegisterInfo *TRI,
                                          const MachineFunction &MF)