commit f57d7d82372c130538f70e2ae68dc4e072d73872
author Luke Cheeseman <luke.cheeseman@arm.com> Tue Dec 18 10:37:42 2018 +0000
committer Luke Cheeseman <luke.cheeseman@arm.com> Tue Dec 18 10:37:42 2018 +0000
tree 3e28c75f2e7d7de67df782f22e6108e4f15cab0b
parent ba8e84b31c4297a8117f27cc42adec8e2493c7e6

[AArch64] - Return address signing dwarf support

- Reapply changes intially introduced in r343089
- The archtecture info is no longer loaded whenever a DWARFContext is created
- The runtimes libraries (santiziers) make use of the dwarf context classes but
  do not intialise the target info
- The architecture of the object can be obtained without loading the target info
- Adding a method to the dwarf context to get this information and multiplex the
  string printing later on

Differential Revision: https://reviews.llvm.org/D55774

llvm-svn: 349472

llvm/lib/MC/MCAsmStreamer.cpp

diff --git a/llvm/lib/MC/MCAsmStreamer.cpp b/llvm/lib/MC/MCAsmStreamer.cpp
index 0daec98..fd10c69 100644
--- a/llvm/lib/MC/MCAsmStreamer.cpp
+++ b/llvm/lib/MC/MCAsmStreamer.cpp
@@ -285,6 +285,7 @@
   void EmitCFIUndefined(int64_t Register) override;
   void EmitCFIRegister(int64_t Register1, int64_t Register2) override;
   void EmitCFIWindowSave() override;
+  void EmitCFINegateRAState() override;
   void EmitCFIReturnColumn(int64_t Register) override;
 
   void EmitWinCFIStartProc(const MCSymbol *Symbol, SMLoc Loc) override;
@@ -1586,6 +1587,12 @@
   EmitEOL();
 }
 
+void MCAsmStreamer::EmitCFINegateRAState() {
+  MCStreamer::EmitCFINegateRAState();
+  OS << "\t.cfi_negate_ra_state";
+  EmitEOL();
+}
+
 void MCAsmStreamer::EmitCFIReturnColumn(int64_t Register) {
   MCStreamer::EmitCFIReturnColumn(Register);
   OS << "\t.cfi_return_column " << Register;

llvm/lib/MC/MCDwarf.cpp

diff --git a/llvm/lib/MC/MCDwarf.cpp b/llvm/lib/MC/MCDwarf.cpp
index 66dfe7b..9791fb5 100644
--- a/llvm/lib/MC/MCDwarf.cpp
+++ b/llvm/lib/MC/MCDwarf.cpp
@@ -1332,6 +1332,10 @@
     Streamer.EmitIntValue(dwarf::DW_CFA_GNU_window_save, 1);
     return;
 
+  case MCCFIInstruction::OpNegateRAState:
+    Streamer.EmitIntValue(dwarf::DW_CFA_AARCH64_negate_ra_state, 1);
+    return;
+
   case MCCFIInstruction::OpUndefined: {
     unsigned Reg = Instr.getRegister();
     Streamer.EmitIntValue(dwarf::DW_CFA_undefined, 1);

llvm/lib/MC/MCStreamer.cpp

diff --git a/llvm/lib/MC/MCStreamer.cpp b/llvm/lib/MC/MCStreamer.cpp
index 733dd40..85e69f6 100644
--- a/llvm/lib/MC/MCStreamer.cpp
+++ b/llvm/lib/MC/MCStreamer.cpp
@@ -577,6 +577,15 @@
   CurFrame->Instructions.push_back(Instruction);
 }
 
+void MCStreamer::EmitCFINegateRAState() {
+  MCSymbol *Label = EmitCFILabel();
+  MCCFIInstruction Instruction = MCCFIInstruction::createNegateRAState(Label);
+  MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
+  if (!CurFrame)
+    return;
+  CurFrame->Instructions.push_back(Instruction);
+}
+
 void MCStreamer::EmitCFIReturnColumn(int64_t Register) {
   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
   if (!CurFrame)