AMDGPU: Skip all meta instructions in hazard recognizer

[arsenm]

Summary

This was not adding a necessary nop due to thinking the kill counted.

[arsenm]

85490874b23ba1337210dbcb700b258ffb751b78

llvm/lib/Target/AMDGPU/GCNHazardRecognizer.cpp

static int getWaitStatesSince(GCNHazardRecognizer::IsHazardFn IsHazard,
   for (auto E = MBB->instr_rend(); I != E; ++I) {
     // Don't add WaitStates for parent BUNDLE instructions.
     if (I->isBundle())
       continue;
 
     if (IsHazard(&*I))
       return WaitStates;
 
-    if (I->isInlineAsm() || I->isImplicitDef() || I->isDebugInstr())
+    if (I->isInlineAsm() || I->isMetaInstruction())
       continue;
 
     WaitStates += SIInstrInfo::getNumWaitStates(*I);
 
     if (IsExpired(&*I, WaitStates))
       return std::numeric_limits<int>::max();
   }
 

llvm/test/CodeGen/AMDGPU/hazard-recognizer-meta-insts.mir

+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
+# RUN: llc -march=amdgcn -mcpu=gfx906 -run-pass=post-RA-hazard-rec -o - %s | FileCheck -check-prefix=GFX9 %s
+
+# Make sure the kill is skipped for hazard purposes, so the nop is
+# correctly inserted.
+
+---
+
+name: global_store_dwordx4_data_hazard_kill
+
+body:             |
+  bb.0:
+    liveins: $vgpr0_vgpr1, $vgpr2_vgpr3_vgpr4_vgpr5
+    ; GFX9-LABEL: name: global_store_dwordx4_data_hazard_kill
+    ; GFX9: GLOBAL_STORE_DWORDX4 $vgpr0_vgpr1, $vgpr2_vgpr3_vgpr4_vgpr5, 0, 0, 0, 0, implicit $exec
+    ; GFX9: $vgpr2 = KILL
+    ; GFX9: S_NOP 0
+    ; GFX9: $vgpr2 = V_MOV_B32_e32 0, implicit $exec
+    GLOBAL_STORE_DWORDX4 $vgpr0_vgpr1, $vgpr2_vgpr3_vgpr4_vgpr5, 0, 0, 0, 0, implicit $exec
+    $vgpr2 = KILL
+    $vgpr2 = V_MOV_B32_e32 0, implicit $exec
+
+...
+
+---
+
+name: global_store_dwordx3_data_hazard_kill
+
+body:             |
+  bb.0:
+    liveins: $vgpr0_vgpr1, $vgpr2_vgpr3_vgpr4
+    ; GFX9-LABEL: name: global_store_dwordx3_data_hazard_kill
+    ; GFX9: GLOBAL_STORE_DWORDX3 $vgpr0_vgpr1, $vgpr2_vgpr3_vgpr4, 0, 0, 0, 0, implicit $exec
+    ; GFX9: $vgpr2 = KILL
+    ; GFX9: S_NOP 0
+    ; GFX9: $vgpr2 = V_MOV_B32_e32 0, implicit $exec
+    GLOBAL_STORE_DWORDX3 $vgpr0_vgpr1, $vgpr2_vgpr3_vgpr4, 0, 0, 0, 0, implicit $exec
+    $vgpr2 = KILL
+    $vgpr2 = V_MOV_B32_e32 0, implicit $exec
+
+...