From 19a3ba35df240471e549b2c4d0c7da390ec0064d Mon Sep 17 00:00:00 2001
From: Martin Storsjo <martin@martin.st>
Date: Fri, 3 Nov 2017 07:33:20 +0000
Subject: [PATCH] [AArch64] Use dwarf exception handling on MinGW

Ideally we should probably produce WinEH here as well, but until
then, we can use dwarf exceptions, without any further changes
required in clang, libunwind or libcxxabi.

Differential Revision: https://reviews.llvm.org/D39535

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317304 91177308-0d34-0410-b5e6-96231b3b80d8
---
 .../AArch64/MCTargetDesc/AArch64MCAsmInfo.cpp |  4 ++-
 .../MCTargetDesc/AArch64WinCOFFStreamer.cpp   |  8 +++++
 test/CodeGen/AArch64/dwarf-cfi.ll             | 36 +++++++++++++++++++
 3 files changed, 47 insertions(+), 1 deletion(-)
 create mode 100644 test/CodeGen/AArch64/dwarf-cfi.ll

diff --git a/lib/Target/AArch64/MCTargetDesc/AArch64MCAsmInfo.cpp b/lib/Target/AArch64/MCTargetDesc/AArch64MCAsmInfo.cpp
index 7fba4849438..c5da457c38f 100644
--- a/lib/Target/AArch64/MCTargetDesc/AArch64MCAsmInfo.cpp
+++ b/lib/Target/AArch64/MCTargetDesc/AArch64MCAsmInfo.cpp
@@ -106,13 +106,15 @@ AArch64MCAsmInfoCOFF::AArch64MCAsmInfoCOFF() {
   PrivateLabelPrefix = ".L";
   AlignmentIsInBytes = false;
   SupportsDebugInformation = true;
-  ExceptionsType = ExceptionHandling::WinEH;
+  CodePointerSize = 8;
 }
 
 AArch64MCAsmInfoMicrosoftCOFF::AArch64MCAsmInfoMicrosoftCOFF() {
   CommentString = ";";
+  ExceptionsType = ExceptionHandling::WinEH;
 }
 
 AArch64MCAsmInfoGNUCOFF::AArch64MCAsmInfoGNUCOFF() {
   CommentString = "//";
+  ExceptionsType = ExceptionHandling::DwarfCFI;
 }
diff --git a/lib/Target/AArch64/MCTargetDesc/AArch64WinCOFFStreamer.cpp b/lib/Target/AArch64/MCTargetDesc/AArch64WinCOFFStreamer.cpp
index 9d0f39e5f6a..c88363d2c25 100644
--- a/lib/Target/AArch64/MCTargetDesc/AArch64WinCOFFStreamer.cpp
+++ b/lib/Target/AArch64/MCTargetDesc/AArch64WinCOFFStreamer.cpp
@@ -23,7 +23,15 @@ public:
                          std::unique_ptr<MCCodeEmitter> CE,
                          raw_pwrite_stream &OS)
       : MCWinCOFFStreamer(C, std::move(AB), std::move(CE), OS) {}
+
+  void FinishImpl() override;
 };
+
+void AArch64WinCOFFStreamer::FinishImpl() {
+  EmitFrames(nullptr);
+
+  MCWinCOFFStreamer::FinishImpl();
+}
 } // end anonymous namespace
 
 namespace llvm {
diff --git a/test/CodeGen/AArch64/dwarf-cfi.ll b/test/CodeGen/AArch64/dwarf-cfi.ll
new file mode 100644
index 00000000000..a75bcd19c69
--- /dev/null
+++ b/test/CodeGen/AArch64/dwarf-cfi.ll
@@ -0,0 +1,36 @@
+; RUN: llc -mtriple aarch64-windows-gnu -filetype=asm -o - %s | FileCheck %s
+
+define void @_Z1gv() personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
+entry:
+  invoke void @_Z1fv()
+          to label %try.cont unwind label %lpad
+
+lpad:
+  %0 = landingpad { i8*, i32 }
+          catch i8* null
+  %1 = extractvalue { i8*, i32 } %0, 0
+  %2 = tail call i8* @__cxa_begin_catch(i8* %1) #2
+  tail call void @__cxa_end_catch()
+  br label %try.cont
+
+try.cont:
+  ret void
+}
+
+declare void @_Z1fv()
+
+declare i32 @__gxx_personality_v0(...)
+
+declare i8* @__cxa_begin_catch(i8*)
+
+declare void @__cxa_end_catch()
+
+; CHECK-LABEL: _Z1gv:
+; CHECK:    .cfi_startproc
+; CHECK:    .cfi_personality 0, __gxx_personality_v0
+; CHECK:    .cfi_lsda 0, .Lexception0
+; CHECK:    str x30, [sp, #-16]!
+; CHECK:    .cfi_def_cfa_offset 16
+; CHECK:    .cfi_offset w30, -16
+; CHECK:    ldr x30, [sp], #16
+; CHECK:    .cfi_endproc
-- 
2.50.1