[PATCH] D51180: [LLD] Check for too large offsets into merge sections earlier to avoid DenseMap tombstone collision

[ben via Phabricator via llvm-commits]

This revision was automatically updated to reflect the committed changes.
Closed by commit rL341206: [LLD] Check too large offsets into merge sections earlier (authored by bd1976llvm, committed by ).
Herald added a subscriber: llvm-commits.

Changed prior to commit:
  https://reviews.llvm.org/D51180?vs=162251&id=163508#toc

Repository:
  rL LLVM

https://reviews.llvm.org/D51180

Files:
  lld/trunk/ELF/InputSection.cpp
  lld/trunk/test/ELF/merge-string-error.s
  lld/trunk/test/ELF/relocation-past-merge-end.s


Index: lld/trunk/test/ELF/merge-string-error.s
===================================================================
--- lld/trunk/test/ELF/merge-string-error.s
+++ lld/trunk/test/ELF/merge-string-error.s
@@ -8,4 +8,4 @@
         .data
         .long .rodata.str1.1 + 4
 
-// CHECK: merge-string-error.s.tmp.o:(.rodata.str1.1): entry is past the end of the section
+// CHECK: merge-string-error.s.tmp.o:(.rodata.str1.1): offset is outside the section
Index: lld/trunk/test/ELF/relocation-past-merge-end.s
===================================================================
--- lld/trunk/test/ELF/relocation-past-merge-end.s
+++ lld/trunk/test/ELF/relocation-past-merge-end.s
@@ -1,7 +1,7 @@
 // REQUIRES: x86
 // RUN: llvm-mc %s -o %t.o -filetype=obj -triple=x86_64-pc-linux
 // RUN: not ld.lld %t.o -o /dev/null -shared 2>&1 | FileCheck %s
-// CHECK: relocation-past-merge-end.s.tmp.o:(.foo): entry is past the end of the section
+// CHECK: relocation-past-merge-end.s.tmp.o:(.foo): offset is outside the section
 
 .data
 .long .foo + 10
Index: lld/trunk/ELF/InputSection.cpp
===================================================================
--- lld/trunk/ELF/InputSection.cpp
+++ lld/trunk/ELF/InputSection.cpp
@@ -1149,43 +1149,32 @@
   return Comp(Value, *First) ? First : First + 1;
 }
 
-// Do binary search to get a section piece at a given input offset.
-static SectionPiece *findSectionPiece(MergeInputSection *Sec, uint64_t Offset) {
-  if (Sec->Data.size() <= Offset)
-    fatal(toString(Sec) + ": entry is past the end of the section");
-
-  // Find the element this offset points to.
-  auto I = fastUpperBound(
-      Sec->Pieces.begin(), Sec->Pieces.end(), Offset,
-      [](const uint64_t &A, const SectionPiece &B) { return A < B.InputOff; });
-  --I;
-  return &*I;
-}
-
 SectionPiece *MergeInputSection::getSectionPiece(uint64_t Offset) {
+  if (this->Data.size() <= Offset)
+    fatal(toString(this) + ": offset is outside the section");
+
   // Find a piece starting at a given offset.
   auto It = OffsetMap.find(Offset);
   if (It != OffsetMap.end())
     return &Pieces[It->second];
 
   // If Offset is not at beginning of a section piece, it is not in the map.
-  // In that case we need to search from the original section piece vector.
-  return findSectionPiece(this, Offset);
+  // In that case we need to  do a binary search of the original section piece vector.
+  auto I = fastUpperBound(
+      Pieces.begin(), Pieces.end(), Offset,
+      [](const uint64_t &A, const SectionPiece &B) { return A < B.InputOff; });
+  --I;
+  return &*I;
 }
 
 // Returns the offset in an output section for a given input offset.
 // Because contents of a mergeable section is not contiguous in output,
 // it is not just an addition to a base output offset.
 uint64_t MergeInputSection::getParentOffset(uint64_t Offset) const {
-  // Find a string starting at a given offset.
-  auto It = OffsetMap.find(Offset);
-  if (It != OffsetMap.end())
-    return Pieces[It->second].OutputOff;
-
   // If Offset is not at beginning of a section piece, it is not in the map.
   // In that case we need to search from the original section piece vector.
   const SectionPiece &Piece =
-      *findSectionPiece(const_cast<MergeInputSection *>(this), Offset);
+      *(const_cast<MergeInputSection *>(this)->getSectionPiece (Offset));
   uint64_t Addend = Offset - Piece.InputOff;
   return Piece.OutputOff + Addend;
 }


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D51180.163508.patch
Type: text/x-patch
Size: 3424 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20180831/79746c73/attachment.bin>