From fb28bf3fb42e2e4ce9b606bcdd855c960b4592f1 Mon Sep 17 00:00:00 2001
From: Stanislav Mekhanoshin <Stanislav.Mekhanoshin@amd.com>
Date: Wed, 7 Sep 2022 15:24:11 -0700
Subject: [PATCH] [AMDGPU] Fix liveness verifier error in hazard recognizer

After D133067 we are inserting swaps to use a new physical
register. I have noticed verifier errors about undefined
physical register uses if we are tracking liveness post RA.

We have no access to LIS at this point, so mark new register
uses as undef to calm down the verifier. Liveness should not
matter at this point anyway.

Note the description of the RegState::Undef: "Value of the
register doesn't matter." I.e. it does not say it is strictly
undefined. In fact that is what we really need: this value
does not matter.

I also had to modify the test a bit since with tracking enabled
it does not pass verification even before the recognizer.

Differential Revision: https://reviews.llvm.org/D133459
---
 .../lib/Target/AMDGPU/GCNHazardRecognizer.cpp |  11 +-
 llvm/test/CodeGen/AMDGPU/hazard-shift64.mir   | 150 +++++++++++++-----
 2 files changed, 117 insertions(+), 44 deletions(-)

diff --git a/llvm/lib/Target/AMDGPU/GCNHazardRecognizer.cpp b/llvm/lib/Target/AMDGPU/GCNHazardRecognizer.cpp
index e454d7f34dce..e2579d41b930 100644
--- a/llvm/lib/Target/AMDGPU/GCNHazardRecognizer.cpp
+++ b/llvm/lib/Target/AMDGPU/GCNHazardRecognizer.cpp
@@ -1817,12 +1817,12 @@ bool GCNHazardRecognizer::fixShift64HighRegBug(MachineInstr *MI) {
     runOnInstruction(
         BuildMI(*MBB, MI, DL, TII.get(AMDGPU::V_SWAP_B32), NewAmtLo)
             .addDef(AmtReg - 1)
-            .addReg(AmtReg - 1)
-            .addReg(NewAmtLo));
+            .addReg(AmtReg - 1, RegState::Undef)
+            .addReg(NewAmtLo, RegState::Undef));
   runOnInstruction(BuildMI(*MBB, MI, DL, TII.get(AMDGPU::V_SWAP_B32), NewAmt)
                        .addDef(AmtReg)
-                       .addReg(AmtReg)
-                       .addReg(NewAmt));
+                       .addReg(AmtReg, RegState::Undef)
+                       .addReg(NewAmt, RegState::Undef));
 
   // Instructions emitted after the current instruction will be processed by the
   // parent loop of the hazard recognizer in a natural way.
@@ -1843,11 +1843,14 @@ bool GCNHazardRecognizer::fixShift64HighRegBug(MachineInstr *MI) {
   // hazards related to these register has already been handled.
   Amt->setReg(NewAmt);
   Amt->setIsKill(false);
+  // We do not update liveness, so verifier may see it as undef.
+  Amt->setIsUndef(true);
   if (OverlappedDst)
     MI->getOperand(0).setReg(NewReg);
   if (OverlappedSrc) {
     Src1->setReg(NewReg);
     Src1->setIsKill(false);
+    Src1->setIsUndef(true);
   }
 
   return true;
diff --git a/llvm/test/CodeGen/AMDGPU/hazard-shift64.mir b/llvm/test/CodeGen/AMDGPU/hazard-shift64.mir
index c4cd527823b8..8182f34ec709 100644
--- a/llvm/test/CodeGen/AMDGPU/hazard-shift64.mir
+++ b/llvm/test/CodeGen/AMDGPU/hazard-shift64.mir
@@ -3,6 +3,7 @@
 
 ---
 name:            highest_reg_shift_amt_v7
+tracksRegLiveness: true
 body:             |
   bb.0:
 
@@ -10,8 +11,8 @@ body:             |
     ; GCN: $vgpr7 = IMPLICIT_DEF
     ; GCN-NEXT: $vgpr2_vgpr3 = IMPLICIT_DEF
     ; GCN-NEXT: S_WAITCNT 0
-    ; GCN-NEXT: $vgpr0, $vgpr7 = V_SWAP_B32 $vgpr7, $vgpr0, implicit $exec
-    ; GCN-NEXT: renamable $vgpr2_vgpr3 = V_LSHRREV_B64_e64 $vgpr0, killed $vgpr2_vgpr3, implicit $exec
+    ; GCN-NEXT: $vgpr0, $vgpr7 = V_SWAP_B32 undef $vgpr7, undef $vgpr0, implicit $exec
+    ; GCN-NEXT: renamable $vgpr2_vgpr3 = V_LSHRREV_B64_e64 undef $vgpr0, killed $vgpr2_vgpr3, implicit $exec
     ; GCN-NEXT: $vgpr7, $vgpr0 = V_SWAP_B32 $vgpr0, $vgpr7, implicit $exec
     $vgpr7 = IMPLICIT_DEF
     $vgpr2_vgpr3 = IMPLICIT_DEF
@@ -20,6 +21,7 @@ body:             |
 
 ---
 name:            highest_reg_shift_amt_v15
+tracksRegLiveness: true
 body:             |
   bb.0:
 
@@ -27,8 +29,8 @@ body:             |
     ; GCN: $vgpr15 = IMPLICIT_DEF
     ; GCN-NEXT: $vgpr2_vgpr3 = IMPLICIT_DEF
     ; GCN-NEXT: S_WAITCNT 0
-    ; GCN-NEXT: $vgpr0, $vgpr15 = V_SWAP_B32 $vgpr15, $vgpr0, implicit $exec
-    ; GCN-NEXT: renamable $vgpr2_vgpr3 = V_LSHRREV_B64_e64 $vgpr0, killed $vgpr2_vgpr3, implicit $exec
+    ; GCN-NEXT: $vgpr0, $vgpr15 = V_SWAP_B32 undef $vgpr15, undef $vgpr0, implicit $exec
+    ; GCN-NEXT: renamable $vgpr2_vgpr3 = V_LSHRREV_B64_e64 undef $vgpr0, killed $vgpr2_vgpr3, implicit $exec
     ; GCN-NEXT: $vgpr15, $vgpr0 = V_SWAP_B32 $vgpr0, $vgpr15, implicit $exec
     $vgpr15 = IMPLICIT_DEF
     $vgpr2_vgpr3 = IMPLICIT_DEF
@@ -37,6 +39,7 @@ body:             |
 
 ---
 name:            highest_reg_shift_amt_v255
+tracksRegLiveness: true
 body:             |
   bb.0:
 
@@ -44,8 +47,8 @@ body:             |
     ; GCN: $vgpr255 = IMPLICIT_DEF
     ; GCN-NEXT: $vgpr2_vgpr3 = IMPLICIT_DEF
     ; GCN-NEXT: S_WAITCNT 0
-    ; GCN-NEXT: $vgpr0, $vgpr255 = V_SWAP_B32 $vgpr255, $vgpr0, implicit $exec
-    ; GCN-NEXT: renamable $vgpr2_vgpr3 = V_LSHRREV_B64_e64 $vgpr0, killed $vgpr2_vgpr3, implicit $exec
+    ; GCN-NEXT: $vgpr0, $vgpr255 = V_SWAP_B32 undef $vgpr255, undef $vgpr0, implicit $exec
+    ; GCN-NEXT: renamable $vgpr2_vgpr3 = V_LSHRREV_B64_e64 undef $vgpr0, killed $vgpr2_vgpr3, implicit $exec
     ; GCN-NEXT: $vgpr255, $vgpr0 = V_SWAP_B32 $vgpr0, $vgpr255, implicit $exec
     $vgpr255 = IMPLICIT_DEF
     $vgpr2_vgpr3 = IMPLICIT_DEF
@@ -54,6 +57,7 @@ body:             |
 
 ---
 name:            highest_reg_shift_amt_used_v0_dst
+tracksRegLiveness: true
 body:             |
   bb.0:
 
@@ -61,8 +65,8 @@ body:             |
     ; GCN: $vgpr7 = IMPLICIT_DEF
     ; GCN-NEXT: $vgpr2_vgpr3 = IMPLICIT_DEF
     ; GCN-NEXT: S_WAITCNT 0
-    ; GCN-NEXT: $vgpr4, $vgpr7 = V_SWAP_B32 $vgpr7, $vgpr4, implicit $exec
-    ; GCN-NEXT: renamable $vgpr0_vgpr1 = V_LSHRREV_B64_e64 $vgpr4, killed $vgpr2_vgpr3, implicit $exec
+    ; GCN-NEXT: $vgpr4, $vgpr7 = V_SWAP_B32 undef $vgpr7, undef $vgpr4, implicit $exec
+    ; GCN-NEXT: renamable $vgpr0_vgpr1 = V_LSHRREV_B64_e64 undef $vgpr4, killed $vgpr2_vgpr3, implicit $exec
     ; GCN-NEXT: $vgpr7, $vgpr4 = V_SWAP_B32 $vgpr4, $vgpr7, implicit $exec
     $vgpr7 = IMPLICIT_DEF
     $vgpr2_vgpr3 = IMPLICIT_DEF
@@ -71,6 +75,7 @@ body:             |
 
 ---
 name:            highest_reg_shift_amt_used_v0_src
+tracksRegLiveness: true
 body:             |
   bb.0:
 
@@ -78,8 +83,8 @@ body:             |
     ; GCN: $vgpr7 = IMPLICIT_DEF
     ; GCN-NEXT: $vgpr0_vgpr1 = IMPLICIT_DEF
     ; GCN-NEXT: S_WAITCNT 0
-    ; GCN-NEXT: $vgpr4, $vgpr7 = V_SWAP_B32 $vgpr7, $vgpr4, implicit $exec
-    ; GCN-NEXT: renamable $vgpr2_vgpr3 = V_LSHRREV_B64_e64 $vgpr4, killed $vgpr0_vgpr1, implicit $exec
+    ; GCN-NEXT: $vgpr4, $vgpr7 = V_SWAP_B32 undef $vgpr7, undef $vgpr4, implicit $exec
+    ; GCN-NEXT: renamable $vgpr2_vgpr3 = V_LSHRREV_B64_e64 undef $vgpr4, killed $vgpr0_vgpr1, implicit $exec
     ; GCN-NEXT: $vgpr7, $vgpr4 = V_SWAP_B32 $vgpr4, $vgpr7, implicit $exec
     $vgpr7 = IMPLICIT_DEF
     $vgpr0_vgpr1 = IMPLICIT_DEF
@@ -88,6 +93,7 @@ body:             |
 
 ---
 name:            highest_reg_shift_amt_used_v0_both
+tracksRegLiveness: true
 body:             |
   bb.0:
 
@@ -95,8 +101,8 @@ body:             |
     ; GCN: $vgpr7 = IMPLICIT_DEF
     ; GCN-NEXT: $vgpr0_vgpr1 = IMPLICIT_DEF
     ; GCN-NEXT: S_WAITCNT 0
-    ; GCN-NEXT: $vgpr2, $vgpr7 = V_SWAP_B32 $vgpr7, $vgpr2, implicit $exec
-    ; GCN-NEXT: renamable $vgpr0_vgpr1 = V_LSHRREV_B64_e64 $vgpr2, killed $vgpr0_vgpr1, implicit $exec
+    ; GCN-NEXT: $vgpr2, $vgpr7 = V_SWAP_B32 undef $vgpr7, undef $vgpr2, implicit $exec
+    ; GCN-NEXT: renamable $vgpr0_vgpr1 = V_LSHRREV_B64_e64 undef $vgpr2, killed $vgpr0_vgpr1, implicit $exec
     ; GCN-NEXT: $vgpr7, $vgpr2 = V_SWAP_B32 $vgpr2, $vgpr7, implicit $exec
     $vgpr7 = IMPLICIT_DEF
     $vgpr0_vgpr1 = IMPLICIT_DEF
@@ -105,6 +111,7 @@ body:             |
 
 ---
 name:            highest_reg_shift_amt_overlapped_src
+tracksRegLiveness: true
 body:             |
   bb.0:
 
@@ -112,9 +119,9 @@ body:             |
     ; GCN: $vgpr7 = IMPLICIT_DEF
     ; GCN-NEXT: $vgpr6_vgpr7 = IMPLICIT_DEF
     ; GCN-NEXT: S_WAITCNT 0
-    ; GCN-NEXT: $vgpr2, $vgpr6 = V_SWAP_B32 $vgpr6, $vgpr2, implicit $exec
-    ; GCN-NEXT: $vgpr3, $vgpr7 = V_SWAP_B32 $vgpr7, $vgpr3, implicit $exec
-    ; GCN-NEXT: renamable $vgpr0_vgpr1 = V_LSHRREV_B64_e64 $vgpr3, $vgpr2_vgpr3, implicit $exec
+    ; GCN-NEXT: $vgpr2, $vgpr6 = V_SWAP_B32 undef $vgpr6, undef $vgpr2, implicit $exec
+    ; GCN-NEXT: $vgpr3, $vgpr7 = V_SWAP_B32 undef $vgpr7, undef $vgpr3, implicit $exec
+    ; GCN-NEXT: renamable $vgpr0_vgpr1 = V_LSHRREV_B64_e64 undef $vgpr3, undef $vgpr2_vgpr3, implicit $exec
     ; GCN-NEXT: $vgpr6, $vgpr2 = V_SWAP_B32 $vgpr2, $vgpr6, implicit $exec
     ; GCN-NEXT: $vgpr7, $vgpr3 = V_SWAP_B32 $vgpr3, $vgpr7, implicit $exec
     $vgpr7 = IMPLICIT_DEF
@@ -124,6 +131,7 @@ body:             |
 
 ---
 name:            highest_reg_shift_amt_overlapped_dst
+tracksRegLiveness: true
 body:             |
   bb.0:
 
@@ -131,9 +139,9 @@ body:             |
     ; GCN: $vgpr7 = IMPLICIT_DEF
     ; GCN-NEXT: $vgpr0_vgpr1 = IMPLICIT_DEF
     ; GCN-NEXT: S_WAITCNT 0
-    ; GCN-NEXT: $vgpr2, $vgpr6 = V_SWAP_B32 $vgpr6, $vgpr2, implicit $exec
-    ; GCN-NEXT: $vgpr3, $vgpr7 = V_SWAP_B32 $vgpr7, $vgpr3, implicit $exec
-    ; GCN-NEXT: $vgpr2_vgpr3 = V_LSHRREV_B64_e64 $vgpr3, killed $vgpr0_vgpr1, implicit $exec
+    ; GCN-NEXT: $vgpr2, $vgpr6 = V_SWAP_B32 undef $vgpr6, undef $vgpr2, implicit $exec
+    ; GCN-NEXT: $vgpr3, $vgpr7 = V_SWAP_B32 undef $vgpr7, undef $vgpr3, implicit $exec
+    ; GCN-NEXT: $vgpr2_vgpr3 = V_LSHRREV_B64_e64 undef $vgpr3, killed $vgpr0_vgpr1, implicit $exec
     ; GCN-NEXT: $vgpr6, $vgpr2 = V_SWAP_B32 $vgpr2, $vgpr6, implicit $exec
     ; GCN-NEXT: $vgpr7, $vgpr3 = V_SWAP_B32 $vgpr3, $vgpr7, implicit $exec
     $vgpr7 = IMPLICIT_DEF
@@ -143,6 +151,7 @@ body:             |
 
 ---
 name:            highest_reg_shift_amt_overlapped_both
+tracksRegLiveness: true
 body:             |
   bb.0:
 
@@ -150,9 +159,9 @@ body:             |
     ; GCN: $vgpr7 = IMPLICIT_DEF
     ; GCN-NEXT: $vgpr6_vgpr7 = IMPLICIT_DEF
     ; GCN-NEXT: S_WAITCNT 0
-    ; GCN-NEXT: $vgpr0, $vgpr6 = V_SWAP_B32 $vgpr6, $vgpr0, implicit $exec
-    ; GCN-NEXT: $vgpr1, $vgpr7 = V_SWAP_B32 $vgpr7, $vgpr1, implicit $exec
-    ; GCN-NEXT: $vgpr0_vgpr1 = V_LSHRREV_B64_e64 $vgpr1, $vgpr0_vgpr1, implicit $exec
+    ; GCN-NEXT: $vgpr0, $vgpr6 = V_SWAP_B32 undef $vgpr6, undef $vgpr0, implicit $exec
+    ; GCN-NEXT: $vgpr1, $vgpr7 = V_SWAP_B32 undef $vgpr7, undef $vgpr1, implicit $exec
+    ; GCN-NEXT: $vgpr0_vgpr1 = V_LSHRREV_B64_e64 undef $vgpr1, undef $vgpr0_vgpr1, implicit $exec
     ; GCN-NEXT: $vgpr6, $vgpr0 = V_SWAP_B32 $vgpr0, $vgpr6, implicit $exec
     ; GCN-NEXT: $vgpr7, $vgpr1 = V_SWAP_B32 $vgpr1, $vgpr7, implicit $exec
     $vgpr7 = IMPLICIT_DEF
@@ -162,6 +171,7 @@ body:             |
 
 ---
 name:            highest_reg_shift_amt_hazard_in_swap
+tracksRegLiveness: true
 body:             |
   bb.0:
 
@@ -171,8 +181,8 @@ body:             |
     ; GCN-NEXT: $vgpr4_vgpr5 = V_MFMA_F64_4X4X4F64_vgprcd_e64 $vgpr0_vgpr1, $vgpr0_vgpr1, $vgpr0_vgpr1, 0, 0, 0, implicit $mode, implicit $exec
     ; GCN-NEXT: S_WAITCNT 0
     ; GCN-NEXT: S_NOP 4
-    ; GCN-NEXT: $vgpr4, $vgpr7 = V_SWAP_B32 $vgpr7, $vgpr4, implicit $exec
-    ; GCN-NEXT: renamable $vgpr2_vgpr3 = V_LSHRREV_B64_e64 $vgpr4, killed $vgpr0_vgpr1, implicit $exec
+    ; GCN-NEXT: $vgpr4, $vgpr7 = V_SWAP_B32 undef $vgpr7, undef $vgpr4, implicit $exec
+    ; GCN-NEXT: renamable $vgpr2_vgpr3 = V_LSHRREV_B64_e64 undef $vgpr4, killed $vgpr0_vgpr1, implicit $exec
     ; GCN-NEXT: $vgpr7, $vgpr4 = V_SWAP_B32 $vgpr4, $vgpr7, implicit $exec
     $vgpr7 = IMPLICIT_DEF
     $vgpr0_vgpr1 = IMPLICIT_DEF
@@ -182,20 +192,23 @@ body:             |
 
 ---
 name:            highest_reg_shift_amt_hazard_in_swap2
+tracksRegLiveness: true
 body:             |
   bb.0:
 
     ; GCN-LABEL: name: highest_reg_shift_amt_hazard_in_swap2
-    ; GCN: $vgpr7 = IMPLICIT_DEF
+    ; GCN: $vgpr1 = IMPLICIT_DEF
+    ; GCN-NEXT: $vgpr7 = IMPLICIT_DEF
     ; GCN-NEXT: $vgpr6_vgpr7 = IMPLICIT_DEF
     ; GCN-NEXT: $vgpr1 = V_DOT4C_I32_I8_e32 $vgpr7, $vgpr7, $vgpr1, implicit $exec
     ; GCN-NEXT: S_WAITCNT 0
-    ; GCN-NEXT: $vgpr0, $vgpr6 = V_SWAP_B32 $vgpr6, $vgpr0, implicit $exec
+    ; GCN-NEXT: $vgpr0, $vgpr6 = V_SWAP_B32 undef $vgpr6, undef $vgpr0, implicit $exec
     ; GCN-NEXT: S_NOP 0
-    ; GCN-NEXT: $vgpr1, $vgpr7 = V_SWAP_B32 $vgpr7, $vgpr1, implicit $exec
-    ; GCN-NEXT: $vgpr0_vgpr1 = V_LSHRREV_B64_e64 $vgpr1, $vgpr0_vgpr1, implicit $exec
+    ; GCN-NEXT: $vgpr1, $vgpr7 = V_SWAP_B32 undef $vgpr7, undef $vgpr1, implicit $exec
+    ; GCN-NEXT: $vgpr0_vgpr1 = V_LSHRREV_B64_e64 undef $vgpr1, undef $vgpr0_vgpr1, implicit $exec
     ; GCN-NEXT: $vgpr6, $vgpr0 = V_SWAP_B32 $vgpr0, $vgpr6, implicit $exec
     ; GCN-NEXT: $vgpr7, $vgpr1 = V_SWAP_B32 $vgpr1, $vgpr7, implicit $exec
+    $vgpr1 = IMPLICIT_DEF
     $vgpr7 = IMPLICIT_DEF
     $vgpr6_vgpr7 = IMPLICIT_DEF
     $vgpr1 = V_DOT4C_I32_I8_e32 $vgpr7, $vgpr7, $vgpr1, implicit $exec
@@ -204,47 +217,104 @@ body:             |
 
 ---
 name:            highest_reg_shift_amt_v7_bundle
+tracksRegLiveness: true
 body:             |
   bb.0:
 
     ; GCN-LABEL: name: highest_reg_shift_amt_v7_bundle
-    ; GCN: BUNDLE implicit-def $vgpr2_vgpr3, implicit-def $vgpr7 {
-    ; GCN-NEXT:   $vgpr7 = IMPLICIT_DEF
-    ; GCN-NEXT:   $vgpr2_vgpr3 = IMPLICIT_DEF
+    ; GCN: $vgpr7 = IMPLICIT_DEF
+    ; GCN-NEXT: $vgpr2_vgpr3 = IMPLICIT_DEF
+    ; GCN-NEXT: BUNDLE implicit-def $vgpr2_vgpr3, implicit-def $vgpr7 {
     ; GCN-NEXT:   S_WAITCNT 0
-    ; GCN-NEXT:   $vgpr0, $vgpr7 = V_SWAP_B32 $vgpr7, $vgpr0, implicit $exec
-    ; GCN-NEXT:   renamable $vgpr2_vgpr3 = V_LSHRREV_B64_e64 $vgpr0, killed $vgpr2_vgpr3, implicit $exec
+    ; GCN-NEXT:   $vgpr0, $vgpr7 = V_SWAP_B32 undef $vgpr7, undef $vgpr0, implicit $exec
+    ; GCN-NEXT:   renamable $vgpr2_vgpr3 = V_LSHRREV_B64_e64 undef $vgpr0, killed $vgpr2_vgpr3, implicit $exec
     ; GCN-NEXT: }
     ; GCN-NEXT: $vgpr7, $vgpr0 = V_SWAP_B32 $vgpr0, $vgpr7, implicit $exec
+    $vgpr7 = IMPLICIT_DEF
+    $vgpr2_vgpr3 = IMPLICIT_DEF
     BUNDLE implicit-def $vgpr2_vgpr3, implicit-def $vgpr7 {
-      $vgpr7 = IMPLICIT_DEF
-      $vgpr2_vgpr3 = IMPLICIT_DEF
-      renamable $vgpr2_vgpr3 = V_LSHRREV_B64_e64 killed $vgpr7, killed $vgpr2_vgpr3, implicit $exec
+      renamable $vgpr2_vgpr3 = V_LSHRREV_B64_e64 $vgpr7, killed $vgpr2_vgpr3, implicit $exec
     }
 ...
 
 ---
 name:            highest_reg_shift_amt_hazard_in_swap2_bundle
+tracksRegLiveness: true
 body:             |
   bb.0:
 
     ; GCN-LABEL: name: highest_reg_shift_amt_hazard_in_swap2_bundle
-    ; GCN: BUNDLE implicit-def $vgpr1, implicit-def $vgpr6_vgpr7 {
+    ; GCN: $vgpr1 = IMPLICIT_DEF
+    ; GCN-NEXT: $vgpr7 = IMPLICIT_DEF
+    ; GCN-NEXT: $vgpr6_vgpr7 = IMPLICIT_DEF
+    ; GCN-NEXT: BUNDLE internal $vgpr7, implicit-def $vgpr1, implicit-def $vgpr6_vgpr7 {
+    ; GCN-NEXT:   $vgpr1 = IMPLICIT_DEF
     ; GCN-NEXT:   $vgpr7 = IMPLICIT_DEF
     ; GCN-NEXT:   $vgpr6_vgpr7 = IMPLICIT_DEF
     ; GCN-NEXT:   $vgpr1 = V_DOT4C_I32_I8_e32 $vgpr7, $vgpr7, $vgpr1, implicit $exec
     ; GCN-NEXT:   S_WAITCNT 0
-    ; GCN-NEXT:   $vgpr0, $vgpr6 = V_SWAP_B32 $vgpr6, $vgpr0, implicit $exec
+    ; GCN-NEXT:   $vgpr0, $vgpr6 = V_SWAP_B32 undef $vgpr6, undef $vgpr0, implicit $exec
     ; GCN-NEXT:   S_NOP 0
-    ; GCN-NEXT:   $vgpr1, $vgpr7 = V_SWAP_B32 $vgpr7, $vgpr1, implicit $exec
-    ; GCN-NEXT:   $vgpr0_vgpr1 = V_LSHRREV_B64_e64 $vgpr1, $vgpr0_vgpr1, implicit $exec
+    ; GCN-NEXT:   $vgpr1, $vgpr7 = V_SWAP_B32 undef $vgpr7, undef $vgpr1, implicit $exec
+    ; GCN-NEXT:   $vgpr0_vgpr1 = V_LSHRREV_B64_e64 undef $vgpr1, undef $vgpr0_vgpr1, implicit $exec
     ; GCN-NEXT: }
     ; GCN-NEXT: $vgpr6, $vgpr0 = V_SWAP_B32 $vgpr0, $vgpr6, implicit $exec
     ; GCN-NEXT: $vgpr7, $vgpr1 = V_SWAP_B32 $vgpr1, $vgpr7, implicit $exec
-    BUNDLE implicit-def $vgpr1, implicit-def $vgpr6_vgpr7 {
+    $vgpr1 = IMPLICIT_DEF
+    $vgpr7 = IMPLICIT_DEF
+    $vgpr6_vgpr7 = IMPLICIT_DEF
+    BUNDLE implicit-def $vgpr1, implicit-def $vgpr6_vgpr7, internal $vgpr7 {
+      $vgpr1 = IMPLICIT_DEF
       $vgpr7 = IMPLICIT_DEF
       $vgpr6_vgpr7 = IMPLICIT_DEF
       $vgpr1 = V_DOT4C_I32_I8_e32 $vgpr7, $vgpr7, $vgpr1, implicit $exec
       renamable $vgpr6_vgpr7 = V_LSHRREV_B64_e64 killed $vgpr7, killed $vgpr6_vgpr7, implicit $exec
     }
 ...
+
+---
+name:            highest_reg_shift_amt_v7_defined
+tracksRegLiveness: true
+body:             |
+  bb.0:
+
+    ; GCN-LABEL: name: highest_reg_shift_amt_v7_defined
+    ; GCN: $vgpr0 = IMPLICIT_DEF
+    ; GCN-NEXT: $vgpr7 = IMPLICIT_DEF
+    ; GCN-NEXT: $vgpr2_vgpr3 = IMPLICIT_DEF
+    ; GCN-NEXT: S_WAITCNT 0
+    ; GCN-NEXT: $vgpr0, $vgpr7 = V_SWAP_B32 undef $vgpr7, undef $vgpr0, implicit $exec
+    ; GCN-NEXT: renamable $vgpr2_vgpr3 = V_LSHRREV_B64_e64 undef $vgpr0, killed $vgpr2_vgpr3, implicit $exec
+    ; GCN-NEXT: $vgpr7, $vgpr0 = V_SWAP_B32 $vgpr0, $vgpr7, implicit $exec
+    $vgpr0 = IMPLICIT_DEF
+    $vgpr7 = IMPLICIT_DEF
+    $vgpr2_vgpr3 = IMPLICIT_DEF
+    renamable $vgpr2_vgpr3 = V_LSHRREV_B64_e64 killed $vgpr7, killed $vgpr2_vgpr3, implicit $exec
+...
+
+---
+name:            highest_reg_shift_amt_hazard_in_swap2_defined
+tracksRegLiveness: true
+body:             |
+  bb.0:
+
+    ; GCN-LABEL: name: highest_reg_shift_amt_hazard_in_swap2_defined
+    ; GCN: $vgpr0 = IMPLICIT_DEF
+    ; GCN-NEXT: $vgpr1 = IMPLICIT_DEF
+    ; GCN-NEXT: $vgpr7 = IMPLICIT_DEF
+    ; GCN-NEXT: $vgpr6_vgpr7 = IMPLICIT_DEF
+    ; GCN-NEXT: $vgpr1 = V_DOT4C_I32_I8_e32 $vgpr7, $vgpr7, $vgpr1, implicit $exec
+    ; GCN-NEXT: S_WAITCNT 0
+    ; GCN-NEXT: $vgpr0, $vgpr6 = V_SWAP_B32 undef $vgpr6, undef $vgpr0, implicit $exec
+    ; GCN-NEXT: S_NOP 0
+    ; GCN-NEXT: $vgpr1, $vgpr7 = V_SWAP_B32 undef $vgpr7, undef $vgpr1, implicit $exec
+    ; GCN-NEXT: $vgpr0_vgpr1 = V_LSHRREV_B64_e64 undef $vgpr1, undef $vgpr0_vgpr1, implicit $exec
+    ; GCN-NEXT: $vgpr6, $vgpr0 = V_SWAP_B32 $vgpr0, $vgpr6, implicit $exec
+    ; GCN-NEXT: $vgpr7, $vgpr1 = V_SWAP_B32 $vgpr1, $vgpr7, implicit $exec
+    $vgpr0 = IMPLICIT_DEF
+    $vgpr1 = IMPLICIT_DEF
+    $vgpr7 = IMPLICIT_DEF
+    $vgpr6_vgpr7 = IMPLICIT_DEF
+    $vgpr1 = V_DOT4C_I32_I8_e32 $vgpr7, $vgpr7, $vgpr1, implicit $exec
+    renamable $vgpr6_vgpr7 = V_LSHRREV_B64_e64 killed $vgpr7, killed $vgpr6_vgpr7, implicit $exec
+...