Test IMPLICIT_DEF. Revert special handling for meta instructions.

Author: jayfoad

llvm/lib/Target/AMDGPU/SIPreEmitPeephole.cpp

@@ -299,7 +299,7 @@ bool SIPreEmitPeephole::optimizeSetGPR(MachineInstr &First,
   for (MachineBasicBlock::instr_iterator I = std::next(First.getIterator()),
                                          E = MI.getIterator();
        I != E; ++I) {
-    if (I->isBundle() || I->isMetaInstruction())
+    if (I->isBundle() || I->isDebugInstr())
       continue;
     switch (I->getOpcode()) {
     case AMDGPU::S_SET_GPR_IDX_MODE:

llvm/test/CodeGen/AMDGPU/set-gpr-idx-peephole.mir

@@ -42,19 +42,21 @@ body:             |
 ...
 
 ---
-name:            kill_in_between
+name:            meta_in_between
 body:             |
   bb.0:
-    ; GCN-LABEL: name: kill_in_between
+    ; GCN-LABEL: name: meta_in_between
     ; GCN: S_SET_GPR_IDX_ON $sgpr2, 1, implicit-def $m0, implicit-def $mode, implicit undef $m0, implicit $mode
     ; GCN-NEXT: $vgpr16 = V_MOV_B32_indirect_read undef $vgpr1, implicit $exec, implicit $m0, implicit $vgpr0_vgpr1_vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15
     ; GCN-NEXT: KILL $sgpr0
+    ; GCN-NEXT: $sgpr0 = IMPLICIT_DEF
     ; GCN-NEXT: $vgpr15 = V_MOV_B32_indirect_read undef $vgpr0, implicit $exec, implicit $m0, implicit killed $vgpr0_vgpr1_vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15
     ; GCN-NEXT: S_SET_GPR_IDX_OFF implicit-def $mode, implicit $mode
   S_SET_GPR_IDX_ON $sgpr2, 1, implicit-def $m0, implicit-def $mode, implicit undef $m0, implicit $mode
   $vgpr16 = V_MOV_B32_indirect_read undef $vgpr1, implicit $exec, implicit $m0, implicit $vgpr0_vgpr1_vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15
   S_SET_GPR_IDX_OFF implicit-def $mode, implicit $mode
   KILL $sgpr0
+  $sgpr0 = IMPLICIT_DEF
   S_SET_GPR_IDX_ON killed $sgpr2, 1, implicit-def $m0, implicit-def $mode, implicit undef $m0, implicit $mode
   $vgpr15 = V_MOV_B32_indirect_read undef $vgpr0, implicit $exec, implicit $m0, implicit killed $vgpr0_vgpr1_vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15
   S_SET_GPR_IDX_OFF implicit-def $mode, implicit $mode