diff options
Diffstat (limited to 'llvm/lib/MC/MCAssembler.cpp')
| -rw-r--r-- | llvm/lib/MC/MCAssembler.cpp | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/llvm/lib/MC/MCAssembler.cpp b/llvm/lib/MC/MCAssembler.cpp index 76be67c..da6516a 100644 --- a/llvm/lib/MC/MCAssembler.cpp +++ b/llvm/lib/MC/MCAssembler.cpp @@ -254,7 +254,7 @@ uint64_t llvm::computeBundlePadding(const MCAssembler &Assembler, else { // EndOfFragment > BundleSize return 2 * BundleSize - EndOfFragment; } - } else if (EndOfFragment > BundleSize) + } else if (OffsetInBundle > 0 && EndOfFragment > BundleSize) return BundleSize - OffsetInBundle; else return 0; @@ -581,16 +581,22 @@ void MCAsmLayout::layoutFragment(MCFragment *F) { // size won't include the padding. // // When the -mc-relax-all flag is used, we optimize bundling by writting the - // bundle padding directly into fragments when the instructions are emitted - // inside the streamer. + // padding directly into fragments when the instructions are emitted inside + // the streamer. When the fragment is larger than the bundle size, we need to + // ensure that it's bundle aligned. This means that if we end up with + // multiple fragments, we must emit bundle padding between fragments. // - if (Assembler.isBundlingEnabled() && !Assembler.getRelaxAll() && - F->hasInstructions()) { + // ".align N" is an example of a directive that introduces multiple + // fragments. We could add a special case to handle ".align N" by emitting + // within-fragment padding (which would produce less padding when N is less + // than the bundle size), but for now we don't. + // + if (Assembler.isBundlingEnabled() && F->hasInstructions()) { assert(isa<MCEncodedFragment>(F) && "Only MCEncodedFragment implementations have instructions"); uint64_t FSize = Assembler.computeFragmentSize(*this, *F); - if (FSize > Assembler.getBundleAlignSize()) + if (!Assembler.getRelaxAll() && FSize > Assembler.getBundleAlignSize()) report_fatal_error("Fragment can't be larger than a bundle size"); uint64_t RequiredBundlePadding = computeBundlePadding(Assembler, F, |