[PATCH] D105054: [lld/mac] Make lld/test/MachO/tlv.s pass with expensive tests

[Nico Weber via Phabricator via llvm-commits]

thakis created this revision.
thakis added a reviewer: lld-macho.
Herald added a subscriber: mgrang.
Herald added a reviewer: int3.
Herald added a reviewer: gkm.
Herald added a project: lld-macho.
thakis requested review of this revision.

The two different thread_local_regular sections (__thread_data and
more_thread_data) had nondeterminstic ordering for two reasons:

1. https://reviews.llvm.org/D102972 changed concatOutputSections from MapVector to DenseMap, so when we iterate it to make output segments, we would add the two sections to the __DATA output segment in nondeterministic order.

2. The same change also moved the two stable_sort()s for segments and sections to sort(). Since sections with assigned priority (such as TLV data) have the same priority for all sections, this is incorrect -- we must use stable_sort() so that the initial (input-order-based) order remains.


https://reviews.llvm.org/D105054

Files:
  lld/MachO/OutputSegment.cpp
  lld/MachO/Writer.cpp


Index: lld/MachO/Writer.cpp
===================================================================
--- lld/MachO/Writer.cpp
+++ lld/MachO/Writer.cpp
@@ -78,7 +78,7 @@
 
   LCUuid *uuidCommand = nullptr;
   OutputSegment *linkEditSegment = nullptr;
-  DenseMap<NamePair, ConcatOutputSection *> concatOutputSections;
+  MapVector<NamePair, ConcatOutputSection *> concatOutputSections;
 };
 
 // LC_DYLD_INFO_ONLY stores the offsets of symbol import/export information.
Index: lld/MachO/OutputSegment.cpp
===================================================================
--- lld/MachO/OutputSegment.cpp
+++ lld/MachO/OutputSegment.cpp
@@ -140,10 +140,13 @@
 }
 
 void OutputSegment::sortOutputSections() {
-  llvm::sort(sections, compareByOrder<OutputSection *>(sectionOrder));
+  llvm::stable_sort(sections, compareByOrder<OutputSection *>(sectionOrder));
 }
 
 void macho::sortOutputSegments() {
+  // sort() instead of stable_sort() is fine because segmentOrder() is
+  // name-based and getOrCreateOutputSegment() makes there's only a single
+  // segment for every name.
   llvm::sort(outputSegments, compareByOrder<OutputSegment *>(segmentOrder));
 }
 


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D105054.354994.patch
Type: text/x-patch
Size: 1155 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20210628/1a0107d7/attachment.bin>