Import LLVM 6.0.1 release including clang, lld and lldb.

"where is the kaboom?" deraadt@

1 files changed, 48 insertions, 8 deletions

diff --git a/gnu/llvm/lib/MC/MCAssembler.cpp b/gnu/llvm/lib/MC/MCAssembler.cpp
index eaf6f19326e..bd881b4d6e8 100644
--- a/gnu/llvm/lib/MC/MCAssembler.cpp
+++ b/gnu/llvm/lib/MC/MCAssembler.cpp
@@ -68,6 +68,10 @@ STATISTIC(FragmentLayouts, "Number of fragment layouts");
 STATISTIC(ObjectBytes, "Number of emitted object file bytes");
 STATISTIC(RelaxationSteps, "Number of assembler layout and relaxation steps");
 STATISTIC(RelaxedInstructions, "Number of relaxed instructions");
+STATISTIC(PaddingFragmentsRelaxations,
+          "Number of Padding Fragments relaxations");
+STATISTIC(PaddingFragmentsBytes,
+          "Total size of all padding from adding Fragments");
 
 } // end namespace stats
 } // end anonymous namespace
@@ -84,7 +88,7 @@ MCAssembler::MCAssembler(MCContext &Context, MCAsmBackend &Backend,
     : Context(Context), Backend(Backend), Emitter(Emitter), Writer(Writer),
       BundleAlignSize(0), RelaxAll(false), SubsectionsViaSymbols(false),
       IncrementalLinkerCompatible(false), ELFHeaderEFlags(0) {
-  VersionMinInfo.Major = 0; // Major version == 0 for "none specified"
+  VersionInfo.Major = 0; // Major version == 0 for "none specified"
 }
 
 MCAssembler::~MCAssembler() = default;
@@ -103,7 +107,7 @@ void MCAssembler::reset() {
   IncrementalLinkerCompatible = false;
   ELFHeaderEFlags = 0;
   LOHContainer.reset();
-  VersionMinInfo.Major = 0;
+  VersionInfo.Major = 0;
 
   // reset objects owned by us
   getBackend().reset();
@@ -277,13 +281,26 @@ uint64_t MCAssembler::computeFragmentSize(const MCAsmLayout &Layout,
     return cast<MCRelaxableFragment>(F).getContents().size();
   case MCFragment::FT_CompactEncodedInst:
     return cast<MCCompactEncodedInstFragment>(F).getContents().size();
-  case MCFragment::FT_Fill:
-    return cast<MCFillFragment>(F).getSize();
+  case MCFragment::FT_Fill: {
+    auto &FF = cast<MCFillFragment>(F);
+    int64_t Size = 0;
+    if (!FF.getSize().evaluateAsAbsolute(Size, Layout))
+      getContext().reportError(FF.getLoc(),
+                               "expected assembly-time absolute expression");
+    if (Size < 0) {
+      getContext().reportError(FF.getLoc(), "invalid number of bytes");
+      return 0;
+    }
+    return Size;
+  }
 
   case MCFragment::FT_LEB:
     return cast<MCLEBFragment>(F).getContents().size();
 
-  case MCFragment::FT_SafeSEH:
+  case MCFragment::FT_Padding:
+    return cast<MCPaddingFragment>(F).getSize();
+
+  case MCFragment::FT_SymbolId:
     return 4;
 
   case MCFragment::FT_Align: {
@@ -533,7 +550,7 @@ static void writeFragment(const MCAssembler &Asm, const MCAsmLayout &Layout,
     for (unsigned I = 1; I < MaxChunkSize; ++I)
       Data[I] = Data[0];
 
-    uint64_t Size = FF.getSize();
+    uint64_t Size = FragmentSize;
     for (unsigned ChunkSize = MaxChunkSize; ChunkSize; ChunkSize /= 2) {
       StringRef Ref(Data, ChunkSize);
       for (uint64_t I = 0, E = Size / ChunkSize; I != E; ++I)
@@ -549,8 +566,15 @@ static void writeFragment(const MCAssembler &Asm, const MCAsmLayout &Layout,
     break;
   }
 
-  case MCFragment::FT_SafeSEH: {
-    const MCSafeSEHFragment &SF = cast<MCSafeSEHFragment>(F);
+  case MCFragment::FT_Padding: {
+    if (!Asm.getBackend().writeNopData(FragmentSize, OW))
+      report_fatal_error("unable to write nop sequence of " +
+                         Twine(FragmentSize) + " bytes");
+    break;
+  }
+
+  case MCFragment::FT_SymbolId: {
+    const MCSymbolIdFragment &SF = cast<MCSymbolIdFragment>(F);
     OW->write32(SF.getSymbol()->getIndex());
     break;
   }
@@ -822,6 +846,19 @@ bool MCAssembler::relaxInstruction(MCAsmLayout &Layout,
   return true;
 }
 
+bool MCAssembler::relaxPaddingFragment(MCAsmLayout &Layout,
+                                       MCPaddingFragment &PF) {
+  uint64_t OldSize = PF.getSize();
+  if (!getBackend().relaxFragment(&PF, Layout))
+    return false;
+  uint64_t NewSize = PF.getSize();
+
+  ++stats::PaddingFragmentsRelaxations;
+  stats::PaddingFragmentsBytes += NewSize;
+  stats::PaddingFragmentsBytes -= OldSize;
+  return true;
+}
+
 bool MCAssembler::relaxLEB(MCAsmLayout &Layout, MCLEBFragment &LF) {
   uint64_t OldSize = LF.getContents().size();
   int64_t Value;
@@ -916,6 +953,9 @@ bool MCAssembler::layoutSectionOnce(MCAsmLayout &Layout, MCSection &Sec) {
     case MCFragment::FT_LEB:
       RelaxedFrag = relaxLEB(Layout, *cast<MCLEBFragment>(I));
       break;
+    case MCFragment::FT_Padding:
+      RelaxedFrag = relaxPaddingFragment(Layout, *cast<MCPaddingFragment>(I));
+      break;
     case MCFragment::FT_CVInlineLines:
       RelaxedFrag =
           relaxCVInlineLineTable(Layout, *cast<MCCVInlineLineTableFragment>(I));