[llvm] r327176 - Revert "[Debug] Retain both sets of debug intrinsics in HoistThenElseCodeToIf"

[Ulrich Weigand via llvm-commits]

Author: uweigand
Date: Fri Mar  9 14:00:10 2018
New Revision: 327176

URL: http://llvm.org/viewvc/llvm-project?rev=327176&view=rev
Log:
Revert "[Debug] Retain both sets of debug intrinsics in HoistThenElseCodeToIf"

This reverts commit r327175 as problems in debug info generation were shown.

Removed:
    llvm/trunk/test/Transforms/SimplifyCFG/hoist-dbgvalue-inlined.ll
Modified:
    llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp

Modified: llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp?rev=327176&r1=327175&r2=327176&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp Fri Mar  9 14:00:10 2018
@@ -1254,23 +1254,23 @@ static bool HoistThenElseCodeToIf(Branch
   BasicBlock::iterator BB2_Itr = BB2->begin();
 
   Instruction *I1 = &*BB1_Itr++, *I2 = &*BB2_Itr++;
-  BasicBlock *BIParent = BI->getParent();
-
-  bool Changed = false;
-  for (;;) {
-    // Move over debug info from both sides unchanged.
-    while (isa<DbgInfoIntrinsic>(I1)) {
-      BIParent->getInstList().splice(BI->getIterator(), BB1->getInstList(), I1);
+  // Skip debug info if it is not identical.
+  DbgInfoIntrinsic *DBI1 = dyn_cast<DbgInfoIntrinsic>(I1);
+  DbgInfoIntrinsic *DBI2 = dyn_cast<DbgInfoIntrinsic>(I2);
+  if (!DBI1 || !DBI2 || !DBI1->isIdenticalToWhenDefined(DBI2)) {
+    while (isa<DbgInfoIntrinsic>(I1))
       I1 = &*BB1_Itr++;
-    }
-    while (isa<DbgInfoIntrinsic>(I2)) {
-      BIParent->getInstList().splice(BI->getIterator(), BB2->getInstList(), I2);
+    while (isa<DbgInfoIntrinsic>(I2))
       I2 = &*BB2_Itr++;
-    }
+  }
+  if (isa<PHINode>(I1) || !I1->isIdenticalToWhenDefined(I2) ||
+      (isa<InvokeInst>(I1) && !isSafeToHoistInvoke(BB1, BB2, I1, I2)))
+    return false;
 
-    if (isa<PHINode>(I1) || !I1->isIdenticalToWhenDefined(I2))
-      return Changed;
+  BasicBlock *BIParent = BI->getParent();
 
+  bool Changed = false;
+  do {
     // If we are hoisting the terminator instruction, don't move one (making a
     // broken BB), instead clone it, and remove BI.
     if (isa<TerminatorInst>(I1))
@@ -1318,7 +1318,18 @@ static bool HoistThenElseCodeToIf(Branch
 
     I1 = &*BB1_Itr++;
     I2 = &*BB2_Itr++;
-  }
+    // Skip debug info if it is not identical.
+    DbgInfoIntrinsic *DBI1 = dyn_cast<DbgInfoIntrinsic>(I1);
+    DbgInfoIntrinsic *DBI2 = dyn_cast<DbgInfoIntrinsic>(I2);
+    if (!DBI1 || !DBI2 || !DBI1->isIdenticalToWhenDefined(DBI2)) {
+      while (isa<DbgInfoIntrinsic>(I1))
+        I1 = &*BB1_Itr++;
+      while (isa<DbgInfoIntrinsic>(I2))
+        I2 = &*BB2_Itr++;
+    }
+  } while (I1->isIdenticalToWhenDefined(I2));
+
+  return true;
 
 HoistTerminator:
   // It may not be possible to hoist an invoke.

Removed: llvm/trunk/test/Transforms/SimplifyCFG/hoist-dbgvalue-inlined.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SimplifyCFG/hoist-dbgvalue-inlined.ll?rev=327175&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/SimplifyCFG/hoist-dbgvalue-inlined.ll (original)
+++ llvm/trunk/test/Transforms/SimplifyCFG/hoist-dbgvalue-inlined.ll (removed)
@@ -1,51 +0,0 @@
-; RUN: opt -simplifycfg -S < %s | FileCheck %s
-; Verify that we don't crash due an invalid !dbg location on the hoisted llvm.dbg.value
-
-define i64 @caller(i64* %ptr, i64 %flag) !dbg !10 {
-init:
-  %v9 = icmp eq i64 %flag, 0
-  br i1 %v9, label %a, label %b
-
-; CHECK:  %vala = load i64, i64* %ptr
-; CHECK-NEXT:  call void @llvm.dbg.value(metadata i64 %vala, metadata [[MD:![0-9]*]]
-; CHECK-NEXT:  call void @llvm.dbg.value(metadata i64 %vala, metadata [[MD]]
-; CHECK-NEXT:  %valbmasked = and i64 %vala, 1
-
-a:                                              ; preds = %init
-  %vala = load i64, i64* %ptr, align 8
-  call void @llvm.dbg.value(metadata i64 %vala, metadata !8, metadata !DIExpression()), !dbg !12
-  br label %test.exit
-
-b:                                              ; preds = %init
-  %valb = load i64, i64* %ptr, align 8
-  call void @llvm.dbg.value(metadata i64 %valb, metadata !8, metadata !DIExpression()), !dbg !13
-  %valbmasked = and i64 %valb, 1
-  br label %test.exit
-
-test.exit:                                      ; preds = %a, %b
-  %retv = phi i64 [ %vala, %a ], [ %valbmasked, %b ]
-  ret i64 %retv
-}
-
-; Function Attrs: nounwind readnone speculatable
-declare void @llvm.dbg.value(metadata, metadata, metadata) #0
-
-attributes #0 = { nounwind readnone speculatable }
-
-!llvm.module.flags = !{!0}
-!llvm.dbg.cu = !{!1}
-
-!0 = !{i32 2, !"Debug Info Version", i32 3}
-!1 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !2, isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !3)
-!2 = !DIFile(filename: "optbug", directory: "")
-!3 = !{}
-!4 = distinct !DISubprogram(name: "callee", scope: !2, file: !2, line: 1, type: !5, isLocal: false, isDefinition: true, scopeLine: 1, isOptimized: false, unit: !1, variables: !7)
-!5 = !DISubroutineType(types: !6)
-!6 = !{null}
-!7 = !{!8}
-!8 = !DILocalVariable(name: "var", scope: !4, file: !2, type: !9)
-!9 = !DIBasicType(name: "var_t", size: 64, encoding: DW_ATE_unsigned)
-!10 = distinct !DISubprogram(name: "caller", scope: !2, file: !2, line: 5, type: !5, isLocal: false, isDefinition: true, scopeLine: 5, isOptimized: false, unit: !1, variables: !3)
-!11 = distinct !DILocation(line: 6, scope: !10)
-!12 = !DILocation(line: 2, scope: !4, inlinedAt: !11)
-!13 = !DILocation(line: 3, scope: !4, inlinedAt: !11)