Add a new 'hotpatch' attribute. This attribute will insert a two-byte no-op

instruction at the beginning of each function that has the attribute, allowing
the function to be easily hooked and/or patched.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117264 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 5 insertions, 0 deletions

diff --git a/lib/AsmParser/LLLexer.cpp b/lib/AsmParser/LLLexer.cpp
index eeaadf68ea..f924b5a908 100644
--- a/lib/AsmParser/LLLexer.cpp
+++ b/lib/AsmParser/LLLexer.cpp
@@ -573,6 +573,7 @@ lltok::Kind LLLexer::LexIdentifier() {
   KEYWORD(noredzone);
   KEYWORD(noimplicitfloat);
   KEYWORD(naked);
+  KEYWORD(hotpatch);
 
   KEYWORD(type);
   KEYWORD(opaque);
diff --git a/lib/AsmParser/LLParser.cpp b/lib/AsmParser/LLParser.cpp
index 4d3bd87932..a1f70fb024 100644
--- a/lib/AsmParser/LLParser.cpp
+++ b/lib/AsmParser/LLParser.cpp
@@ -982,6 +982,7 @@ bool LLParser::ParseOptionalAttrs(unsigned &Attrs, unsigned AttrKind) {
     case lltok::kw_noredzone:       Attrs |= Attribute::NoRedZone; break;
     case lltok::kw_noimplicitfloat: Attrs |= Attribute::NoImplicitFloat; break;
     case lltok::kw_naked:           Attrs |= Attribute::Naked; break;
+    case lltok::kw_hotpatch:        Attrs |= Attribute::Hotpatch; break;
 
     case lltok::kw_alignstack: {
       unsigned Alignment;
diff --git a/lib/AsmParser/LLToken.h b/lib/AsmParser/LLToken.h
index 8a8663e739..72128c9ae0 100644
--- a/lib/AsmParser/LLToken.h
+++ b/lib/AsmParser/LLToken.h
@@ -96,6 +96,7 @@ namespace lltok {
     kw_noredzone,
     kw_noimplicitfloat,
     kw_naked,
+    kw_hotpatch,
 
     kw_type,
     kw_opaque,
diff --git a/lib/VMCore/Attributes.cpp b/lib/VMCore/Attributes.cpp
index 3422faf273..6f5ecd278d 100644
--- a/lib/VMCore/Attributes.cpp
+++ b/lib/VMCore/Attributes.cpp
@@ -70,6 +70,8 @@ std::string Attribute::getAsString(Attributes Attrs) {
     Result += "noimplicitfloat ";
   if (Attrs & Attribute::Naked)
     Result += "naked ";
+  if (Attrs & Attribute::Hotpatch)
+    Result += "hotpatch ";
   if (Attrs & Attribute::StackAlignment) {
     Result += "alignstack(";
     Result += utostr(Attribute::getStackAlignmentFromAttrs(Attrs));