Author: Lydia Kim Date: 2025-11-27T11:38:40+01:00 New Revision: 9ed1927442a4e8f417dbfeeab342a9be4204198e
URL: https://github.com/llvm/llvm-project/commit/9ed1927442a4e8f417dbfeeab342a9be4204198e DIFF: https://github.com/llvm/llvm-project/commit/9ed1927442a4e8f417dbfeeab342a9be4204198e.diff LOG: [server-llvm-21][MC] Fixing vector overflow Summary: Test Plan: Reviewers: Subscribers: Tasks: Tags: Differential Revision: https://phabricator.intern.facebook.com/D87662897 Added: Modified: llvm/include/llvm/MC/MCSection.h llvm/lib/MC/MCSection.cpp Removed: ################################################################################ diff --git a/llvm/include/llvm/MC/MCSection.h b/llvm/include/llvm/MC/MCSection.h index 64b13972bfca1..9daaebf7e7935 100644 --- a/llvm/include/llvm/MC/MCSection.h +++ b/llvm/include/llvm/MC/MCSection.h @@ -298,8 +298,8 @@ class MCFragment { /// data. class MCEncodedFragment : public MCFragment { uint8_t BundlePadding = 0; - uint32_t ContentStart = 0; - uint32_t ContentEnd = 0; + uint32_t ContentSize = 0; + uint64_t ContentStart = 0; uint32_t FixupStart = 0; uint32_t FixupEnd = 0; @@ -360,22 +360,23 @@ class MCEncodedFragment : public MCFragment { // Content-related functions manage parent's storage using ContentStart and // ContentSize. - void clearContents() { ContentEnd = ContentStart; } + void clearContents() { ContentSize = 0; } // Get a SmallVector reference. The caller should call doneAppending to update - // `ContentEnd`. + // `ContentSize`. SmallVectorImpl<char> &getContentsForAppending() { SmallVectorImpl<char> &S = getParent()->ContentStorage; - if (LLVM_UNLIKELY(ContentEnd != S.size())) { + if (LLVM_UNLIKELY(ContentStart + ContentSize != S.size())) { // Move the elements to the end. Reserve space to avoid invalidating // S.begin()+I for `append`. - auto Size = ContentEnd - ContentStart; auto I = std::exchange(ContentStart, S.size()); - S.reserve(S.size() + Size); - S.append(S.begin() + I, S.begin() + I + Size); + S.reserve(S.size() + ContentSize); + S.append(S.begin() + I, S.begin() + I + ContentSize); } return S; } - void doneAppending() { ContentEnd = getParent()->ContentStorage.size(); } + void doneAppending() { + ContentSize = getParent()->ContentStorage.size() - ContentStart; + } void appendContents(ArrayRef<char> Contents) { getContentsForAppending().append(Contents.begin(), Contents.end()); doneAppending(); @@ -387,11 +388,11 @@ class MCEncodedFragment : public MCFragment { LLVM_ABI void setContents(ArrayRef<char> Contents); MutableArrayRef<char> getContents() { return MutableArrayRef(getParent()->ContentStorage) - .slice(ContentStart, ContentEnd - ContentStart); + .slice(ContentStart, ContentSize); } ArrayRef<char> getContents() const { return ArrayRef(getParent()->ContentStorage) - .slice(ContentStart, ContentEnd - ContentStart); + .slice(ContentStart, ContentSize); } // Fixup-related functions manage parent's storage using FixupStart and @@ -409,7 +410,7 @@ class MCEncodedFragment : public MCFragment { .slice(FixupStart, FixupEnd - FixupStart); } - size_t getSize() const { return ContentEnd - ContentStart; } + size_t getSize() const { return ContentSize; } }; /// Fragment for data and encoded instructions. diff --git a/llvm/lib/MC/MCSection.cpp b/llvm/lib/MC/MCSection.cpp index a7330692571de..97f591fbf0e28 100644 --- a/llvm/lib/MC/MCSection.cpp +++ b/llvm/lib/MC/MCSection.cpp @@ -84,11 +84,11 @@ LLVM_DUMP_METHOD void MCSection::dump( void MCEncodedFragment::setContents(ArrayRef<char> Contents) { auto &S = getParent()->ContentStorage; - if (ContentStart + Contents.size() > ContentEnd) { + if (Contents.size() > ContentSize) { ContentStart = S.size(); S.resize_for_overwrite(S.size() + Contents.size()); } - ContentEnd = ContentStart + Contents.size(); + ContentSize = Contents.size(); llvm::copy(Contents, S.begin() + ContentStart); } _______________________________________________ llvm-branch-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
