[llvm] 1833de3 - [Extractor][DebugInfo] Don't pick DebugLocs from dbg intrinsics (#80863)

[via llvm-commits]

Author: Jeremy Morse
Date: 2024-02-06T17:40:32Z
New Revision: 1833de3ee364a996d03bb23b19fe472e3e2ddf3b

URL: https://github.com/llvm/llvm-project/commit/1833de3ee364a996d03bb23b19fe472e3e2ddf3b
DIFF: https://github.com/llvm/llvm-project/commit/1833de3ee364a996d03bb23b19fe472e3e2ddf3b.diff

LOG: [Extractor][DebugInfo] Don't pick DebugLocs from dbg intrinsics (#80863)

When picking the source location for a branch instruction in the
CodeExtractor, we can end up picking the source location of a debugging
intrinsic. This never makes sense because any variable assignment
information (or labels) might originate from completely different
lexical scopes that have been inlined, and also makes the line tables
change between -g and -gmlt. Fix this by skipping debug intrinsics when
looking for branch source locations.

Detected because of test differences with RemoveDIs, the non-intrinsinc
form of debug-info -- fixing in intrinsic form to avoid there being
spurious test differences when we turn it on.

Added: 
    

Modified: 
    llvm/lib/Transforms/Utils/CodeExtractor.cpp
    llvm/test/Transforms/HotColdSplit/split-out-dbg-label.ll
    llvm/test/Transforms/IROutliner/gvn-phi-debug.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Transforms/Utils/CodeExtractor.cpp b/llvm/lib/Transforms/Utils/CodeExtractor.cpp
index 278111883459b..57d3926515993 100644
--- a/llvm/lib/Transforms/Utils/CodeExtractor.cpp
+++ b/llvm/lib/Transforms/Utils/CodeExtractor.cpp
@@ -1769,6 +1769,10 @@ CodeExtractor::extractCodeRegion(const CodeExtractorAnalysisCache &CEAC,
       return any_of(*BB, [&BranchI](const Instruction &I) {
         if (!I.getDebugLoc())
           return false;
+        // Don't use source locations attached to debug-intrinsics: they could
+        // be from completely unrelated scopes.
+        if (isa<DbgInfoIntrinsic>(I))
+          return false;
         BranchI->setDebugLoc(I.getDebugLoc());
         return true;
       });

diff  --git a/llvm/test/Transforms/HotColdSplit/split-out-dbg-label.ll b/llvm/test/Transforms/HotColdSplit/split-out-dbg-label.ll
index 8209f93915e9c..97bb13d4bdcfb 100644
--- a/llvm/test/Transforms/HotColdSplit/split-out-dbg-label.ll
+++ b/llvm/test/Transforms/HotColdSplit/split-out-dbg-label.ll
@@ -18,8 +18,8 @@ target triple = "x86_64-apple-macosx10.14.0"
 ; CHECK: [[FILE:![0-9]+]] = !DIFile
 ; CHECK: [[INLINE_ME_SCOPE:![0-9]+]] = distinct !DISubprogram(name: "inline_me"
 ; CHECK: [[SCOPE:![0-9]+]] = distinct !DISubprogram(name: "foo.cold.1"
-; CHECK: [[LINE]] = !DILocation(line: 1, column: 1, scope: [[SCOPE]]
 ; CHECK: [[LABEL]] = !DILabel(scope: [[SCOPE]], name: "bye", file: [[FILE]], line: 28
+; CHECK: [[LINE]] = !DILocation(line: 1, column: 1, scope: [[SCOPE]]
 ; CHECK: [[LABEL_IN_INLINE_ME]] = !DILabel(scope: [[INLINE_ME_SCOPE]], name: "label_in_ at inline_me", file: [[FILE]], line: 29
 ; CHECK: [[LINE2]] = !DILocation(line: 2, column: 2, scope: [[INLINE_ME_SCOPE]], inlinedAt: [[LINE]]
 ; CHECK: [[SCOPED_LABEL]] = !DILabel(scope: [[SCOPE_IN_FOO:![0-9]+]], name: "scoped_label_in_foo", file: [[FILE]], line: 30

diff  --git a/llvm/test/Transforms/IROutliner/gvn-phi-debug.ll b/llvm/test/Transforms/IROutliner/gvn-phi-debug.ll
index 934bda1fc7c2e..217a8498ffbb3 100644
--- a/llvm/test/Transforms/IROutliner/gvn-phi-debug.ll
+++ b/llvm/test/Transforms/IROutliner/gvn-phi-debug.ll
@@ -1,5 +1,6 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
 ; RUN: opt -S -passes=verify,iroutliner -ir-outlining-no-cost < %s | FileCheck %s
+; RUN: opt -S -passes=verify,iroutliner -ir-outlining-no-cost < %s --try-experimental-debuginfo-iterators | FileCheck %s
 
 target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
 target triple = "thumbv7-none-linux-android19"
@@ -171,7 +172,5 @@ attributes #0 = { nocallback nofree nosync nounwind speculatable willreturn memo
 ; CHECK: [[DBG8]] = distinct !DISubprogram(name: "w", scope: [[META5]], file: [[META5]], line: 54, type: [[META9:![0-9]+]], scopeLine: 54, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: [[META0]], retainedNodes: [[META10:![0-9]+]])
 ; CHECK: [[META9]] = !DISubroutineType(types: [[META10]])
 ; CHECK: [[META10]] = !{}
-; CHECK: [[DBG11]] = !DILocation(line: 0, scope: [[META12:![0-9]+]])
-; CHECK: [[META12]] = distinct !DILexicalBlock(scope: [[META13:![0-9]+]], file: [[META5]], line: 56, column: 17)
-; CHECK: [[META13]] = distinct !DILexicalBlock(scope: [[DBG8]], file: [[META5]], line: 56, column: 11)
+; CHECK: [[DBG11]] = !DILocation(line: 0, scope: [[DBG8]])
 ;.