[llvm] deb2ca5 - Revert "[LiveIntervals] Fix repairOldRegInRange for simple def cases"

[Jay Foad via llvm-commits]

Author: Jay Foad
Date: 2021-09-23T17:55:05+01:00
New Revision: deb2ca566ae70303042e3ab9296978895a817bf8

URL: https://github.com/llvm/llvm-project/commit/deb2ca566ae70303042e3ab9296978895a817bf8
DIFF: https://github.com/llvm/llvm-project/commit/deb2ca566ae70303042e3ab9296978895a817bf8.diff

LOG: Revert "[LiveIntervals] Fix repairOldRegInRange for simple def cases"

This reverts commit 8229cb74125322ff337cfe316ab35c6ebf412bde.

It was failing on buildbots with expensive checks enabled.

Added: 
    

Modified: 
    llvm/lib/CodeGen/LiveIntervals.cpp
    llvm/test/CodeGen/AMDGPU/extract-load-i1.ll
    llvm/test/CodeGen/ARM/signext-inreg.ll
    llvm/test/CodeGen/X86/mul-shift-reassoc.ll

Removed: 
    llvm/test/CodeGen/AMDGPU/twoaddr-regsequence.mir


################################################################################
diff  --git a/llvm/lib/CodeGen/LiveIntervals.cpp b/llvm/lib/CodeGen/LiveIntervals.cpp
index ac6818a27c84e..23036c2b115f8 100644
--- a/llvm/lib/CodeGen/LiveIntervals.cpp
+++ b/llvm/lib/CodeGen/LiveIntervals.cpp
@@ -1571,14 +1571,15 @@ void LiveIntervals::repairOldRegInRange(const MachineBasicBlock::iterator Begin,
                                         LaneBitmask LaneMask) {
   LiveInterval::iterator LII = LR.find(EndIdx);
   SlotIndex lastUseIdx;
-  if (LII != LR.end() && LII->start < EndIdx) {
+  if (LII == LR.begin()) {
+    // This happens when the function is called for a subregister that only
+    // occurs _after_ the range that is to be repaired.
+    return;
+  }
+  if (LII != LR.end() && LII->start < EndIdx)
     lastUseIdx = LII->end;
-  } else if (LII == LR.begin()) {
-    // We may not have a liverange at all if this is a subregister untouched
-    // between \p Begin and \p End.
-  } else {
+  else
     --LII;
-  }
 
   for (MachineBasicBlock::iterator I = End; I != Begin;) {
     --I;

diff  --git a/llvm/test/CodeGen/AMDGPU/extract-load-i1.ll b/llvm/test/CodeGen/AMDGPU/extract-load-i1.ll
index 042de0cc72227..5a4c83d478b0d 100644
--- a/llvm/test/CodeGen/AMDGPU/extract-load-i1.ll
+++ b/llvm/test/CodeGen/AMDGPU/extract-load-i1.ll
@@ -1,6 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
 ; RUN: llc -mtriple=amdgcn-amd-amdhsa < %s | FileCheck %s
-; RUN: llc -mtriple=amdgcn-amd-amdhsa -early-live-intervals < %s | FileCheck %s
 
 ; FIXME: Inefficient codegen which skips an optimization of load +
 ; extractelement when the vector element type is not byte-sized.

diff  --git a/llvm/test/CodeGen/AMDGPU/twoaddr-regsequence.mir b/llvm/test/CodeGen/AMDGPU/twoaddr-regsequence.mir
deleted file mode 100644
index 72cd2eec323fb..0000000000000
--- a/llvm/test/CodeGen/AMDGPU/twoaddr-regsequence.mir
+++ /dev/null
@@ -1,24 +0,0 @@
-# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
-# RUN: llc -mtriple=amdgcn-amd-amdhsa -run-pass=liveintervals,twoaddressinstruction,simple-register-coalescing -verify-machineinstrs -o - %s | FileCheck %s
-
-# Check that LiveIntervals are correctly updated when eliminating REG_SEQUENCE.
----
-name: f
-tracksRegLiveness: true
-body:             |
-  bb.0:
-    liveins: $vgpr0, $vgpr1
-
-    ; CHECK-LABEL: name: f
-    ; CHECK: liveins: $vgpr0, $vgpr1
-    ; CHECK-NEXT: {{  $}}
-    ; CHECK-NEXT: undef %2.sub0:vreg_64 = COPY $vgpr0
-    ; CHECK-NEXT: %2.sub1:vreg_64 = COPY $vgpr1
-    ; CHECK-NEXT: $vgpr2_vgpr3 = COPY %2
-    ; CHECK-NEXT: S_NOP 0, implicit $vgpr2_vgpr3
-    %0:vgpr_32 = COPY $vgpr0
-    %1:vgpr_32 = COPY $vgpr1
-    %35:vreg_64 = REG_SEQUENCE %0, %subreg.sub0, %1, %subreg.sub1
-    $vgpr2_vgpr3 = COPY %35
-    S_NOP 0, implicit $vgpr2_vgpr3
-...

diff  --git a/llvm/test/CodeGen/ARM/signext-inreg.ll b/llvm/test/CodeGen/ARM/signext-inreg.ll
index e41af81956345..dd8b144bbe2b6 100644
--- a/llvm/test/CodeGen/ARM/signext-inreg.ll
+++ b/llvm/test/CodeGen/ARM/signext-inreg.ll
@@ -1,6 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
 ; RUN: llc < %s -mtriple=armv8 | FileCheck %s
-; RUN: llc < %s -mtriple=armv8 -early-live-intervals | FileCheck %s
 define <4 x i32> @test(<4 x i32> %m) {
 ; CHECK-LABEL: test:
 ; CHECK:       @ %bb.0: @ %entry

diff  --git a/llvm/test/CodeGen/X86/mul-shift-reassoc.ll b/llvm/test/CodeGen/X86/mul-shift-reassoc.ll
index 53d7a78e0e0e1..74ae976765dd1 100644
--- a/llvm/test/CodeGen/X86/mul-shift-reassoc.ll
+++ b/llvm/test/CodeGen/X86/mul-shift-reassoc.ll
@@ -1,6 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
 ; RUN: llc < %s -mtriple=i686-- | FileCheck %s
-; RUN: llc < %s -mtriple=i686-- -early-live-intervals | FileCheck %s
 
 define i32 @test(i32 %X, i32 %Y) {
 	; Push the shl through the mul to allow an LEA to be formed, instead