Merge branch 'main' into p/libcxx-gcc15-type-traits

Author: frobtech

.github/workflows/libcxx-build-and-test.yaml

@@ -37,7 +37,7 @@ jobs:
   stage1:
     if: github.repository_owner == 'llvm'
     runs-on: libcxx-self-hosted-linux
-    container: ghcr.io/llvm/libcxx-linux-builder:b6bb9dc5abd7c6452c13a53fa8949cb259db459b
+    container: ghcr.io/llvm/libcxx-linux-builder:2b57ebb50b6d418e70382e655feaa619b558e254
     continue-on-error: false
     strategy:
       fail-fast: false
@@ -75,7 +75,7 @@ jobs:
   stage2:
     if: github.repository_owner == 'llvm'
     runs-on: libcxx-self-hosted-linux
-    container: ghcr.io/llvm/libcxx-linux-builder:b6bb9dc5abd7c6452c13a53fa8949cb259db459b
+    container: ghcr.io/llvm/libcxx-linux-builder:2b57ebb50b6d418e70382e655feaa619b558e254
     needs: [ stage1 ]
     continue-on-error: false
     strategy:
@@ -163,7 +163,7 @@ jobs:
         - config: 'generic-msan'
           machine: libcxx-self-hosted-linux
     runs-on: ${{ matrix.machine }}
-    container: ghcr.io/llvm/libcxx-linux-builder:b6bb9dc5abd7c6452c13a53fa8949cb259db459b
+    container: ghcr.io/llvm/libcxx-linux-builder:2b57ebb50b6d418e70382e655feaa619b558e254
     steps:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
       - name: ${{ matrix.config }}

CONTRIBUTING.md

@@ -9,9 +9,8 @@ describes how to get involved, raise issues and submit patches.
 
 ## Getting in touch
 
-Join the [LLVM Discourse forums](https://discourse.llvm.org/), [Discord
-chat](https://discord.gg/xS7Z362), or #llvm IRC channel on
-[OFTC](https://oftc.net/).
+Join the [LLVM Discourse forums](https://discourse.llvm.org/) or [Discord
+chat](https://discord.gg/xS7Z362).
 
 The LLVM project has adopted a [code of conduct](https://llvm.org/docs/CodeOfConduct.html) for
 participants to all modes of communication within the project.

bolt/Maintainers.txt

@@ -5,9 +5,8 @@ what goes in or not.
 
 The list is sorted by surname and formatted to allow easy grepping and
 beautification by scripts. The fields are: name (N), email (E), web-address
-(W), PGP key ID and fingerprint (P), description (D), snail-mail address
-(S) and (I) IRC handle. Each entry should contain at least the (N), (E) and
-(D) fields.
+(W), PGP key ID and fingerprint (P), and description (D). Each entry should
+contain at least the (N), (E) and (D) fields.
 
 N: Maksim Panchenko, Rafael Auler
 E: [email protected], [email protected]

bolt/include/bolt/Core/BinaryFunction.h

@@ -360,6 +360,11 @@ class BinaryFunction {
   /// True if the function is used for patching code at a fixed address.
   bool IsPatch{false};
 
+  /// True if the original entry point of the function may get called, but the
+  /// original body cannot be executed and needs to be patched with code that
+  /// redirects execution to the new function body.
+  bool NeedsPatch{false};
+
   /// True if the function should not have an associated symbol table entry.
   bool IsAnonymous{false};
 
@@ -1372,6 +1377,9 @@ class BinaryFunction {
   /// Return true if this function is used for patching existing code.
   bool isPatch() const { return IsPatch; }
 
+  /// Return true if the function requires a patch.
+  bool needsPatch() const { return NeedsPatch; }
+
   /// Return true if the function should not have associated symbol table entry.
   bool isAnonymous() const { return IsAnonymous; }
 
@@ -1757,6 +1765,9 @@ class BinaryFunction {
     IsPatch = V;
   }
 
+  /// Mark the function for patching.
+  void setNeedsPatch(bool V) { NeedsPatch = V; }
+
   /// Indicate if the function should have a name in the symbol table.
   void setAnonymous(bool V) {
     assert(isInjected() && "Only injected functions could be anonymous");

bolt/include/bolt/Profile/DataAggregator.h

@@ -197,10 +197,6 @@ class DataAggregator : public DataReader {
 
   BoltAddressTranslation *BAT{nullptr};
 
-  /// Whether pre-aggregated profile needs to convert branch profile into call
-  /// to continuation fallthrough profile.
-  bool NeedsConvertRetProfileToCallCont{false};
-
   /// Update function execution profile with a recorded trace.
   /// A trace is region of code executed between two LBR entries supplied in
   /// execution order.

bolt/include/bolt/Utils/CommandLineOpts.h

@@ -34,6 +34,7 @@ extern llvm::cl::opt<unsigned> AlignText;
 extern llvm::cl::opt<unsigned> AlignFunctions;
 extern llvm::cl::opt<bool> AggregateOnly;
 extern llvm::cl::opt<unsigned> BucketsPerLine;
+extern llvm::cl::opt<bool> CompactCodeModel;
 extern llvm::cl::opt<bool> DiffOnly;
 extern llvm::cl::opt<bool> EnableBAT;
 extern llvm::cl::opt<bool> EqualizeBBCounts;

bolt/lib/Core/BinaryFunction.cpp

@@ -1797,8 +1797,6 @@ bool BinaryFunction::scanExternalRefs() {
     // Create relocation for every fixup.
     for (const MCFixup &Fixup : Fixups) {
       std::optional<Relocation> Rel = BC.MIB->createRelocation(Fixup, *BC.MAB);
-      // Can be skipped in case of overlow during relocation value encoding.
-      Rel->setOptional();
       if (!Rel) {
         Success = false;
         continue;
@@ -1814,6 +1812,17 @@ bool BinaryFunction::scanExternalRefs() {
         Success = false;
         continue;
       }
+
+      if (BC.isAArch64()) {
+        // Allow the relocation to be skipped in case of the overflow during the
+        // relocation value encoding.
+        Rel->setOptional();
+
+        if (!opts::CompactCodeModel)
+          if (BinaryFunction *TargetBF = BC.getFunctionForSymbol(Rel->Symbol))
+            TargetBF->setNeedsPatch(true);
+      }
+
       Rel->Offset += getAddress() - getOriginSection()->getAddress() + Offset;
       FunctionRelocations.push_back(*Rel);
     }

bolt/lib/Core/BinarySection.cpp

@@ -186,16 +186,6 @@ void BinarySection::flushPendingRelocations(raw_pwrite_stream &OS,
         !Relocation::canEncodeValue(Reloc.Type, Value,
                                     SectionAddress + Reloc.Offset)) {
 
-      // A successful run of 'scanExternalRefs' means that all pending
-      // relocations are flushed. Otherwise, PatchEntries should run.
-      if (!opts::ForcePatch) {
-        BC.errs()
-            << "BOLT-ERROR: cannot encode relocation for symbol "
-            << Reloc.Symbol->getName()
-            << " as it is out-of-range. To proceed must use -force-patch\n";
-        exit(1);
-      }
-
       ++SkippedPendingRelocations;
       continue;
     }

bolt/lib/Passes/LongJmp.cpp

@@ -12,6 +12,7 @@
 
 #include "bolt/Passes/LongJmp.h"
 #include "bolt/Core/ParallelUtilities.h"
+#include "bolt/Utils/CommandLineOpts.h"
 #include "llvm/Support/MathExtras.h"
 
 #define DEBUG_TYPE "longjmp"
@@ -26,11 +27,6 @@ extern cl::opt<unsigned> AlignFunctions;
 extern cl::opt<bool> UseOldText;
 extern cl::opt<bool> HotFunctionsAtEnd;
 
-static cl::opt<bool>
-    CompactCodeModel("compact-code-model",
-                     cl::desc("generate code for binaries <128MB on AArch64"),
-                     cl::init(false), cl::cat(BoltCategory));
-
 static cl::opt<bool> GroupStubs("group-stubs",
                                 cl::desc("share stubs across functions"),
                                 cl::init(true), cl::cat(BoltOptCategory));

bolt/lib/Passes/PatchEntries.cpp

@@ -39,7 +39,8 @@ Error PatchEntries::runOnFunctions(BinaryContext &BC) {
     bool NeedsPatching = llvm::any_of(
         llvm::make_second_range(BC.getBinaryFunctions()),
         [&](BinaryFunction &BF) {
-          return !BC.shouldEmit(BF) && !BF.hasExternalRefRelocations();
+          return (!BC.shouldEmit(BF) && !BF.hasExternalRefRelocations()) ||
+                 BF.needsPatch();
         });
 
     if (!NeedsPatching)
@@ -66,7 +67,7 @@ Error PatchEntries::runOnFunctions(BinaryContext &BC) {
 
     // Check if we can skip patching the function.
     if (!opts::ForcePatch && !Function.hasEHRanges() &&
-        Function.getSize() < PatchThreshold)
+        !Function.needsPatch() && Function.getSize() < PatchThreshold)
       continue;
 
     // List of patches for function entries. We either successfully patch