[llvm] r218014 - ARM: prevent crash on ELF directives on COFF

[Saleem Abdulrasool]

Author: compnerd
Date: Wed Sep 17 23:28:29 2014
New Revision: 218014

URL: http://llvm.org/viewvc/llvm-project?rev=218014&view=rev
Log:
ARM: prevent crash on ELF directives on COFF

Certain directives are unsupported on Windows (some of which could/should be
supported).  We would not diagnose the use but rather crash during the emission
as we try to access the Target Streamer.  Add an assertion to prevent creating a
NULL reference (which is not permitted under C++) as well as a test to ensure
that we can diagnose the disabled directives.

Added:
    llvm/trunk/test/MC/ARM/directive-unsupported.s
Modified:
    llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp

Modified: llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp?rev=218014&r1=218013&r2=218014&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp (original)
+++ llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp Wed Sep 17 23:28:29 2014
@@ -135,6 +135,8 @@ class ARMAsmParser : public MCTargetAsmP
   UnwindContext UC;
 
   ARMTargetStreamer &getTargetStreamer() {
+    assert(getParser().getStreamer().getTargetStreamer() &&
+           "do not have a target streamer");
     MCTargetStreamer &TS = *getParser().getStreamer().getTargetStreamer();
     return static_cast<ARMTargetStreamer &>(TS);
   }
@@ -8313,6 +8315,7 @@ bool ARMAsmParser::ParseDirective(AsmTok
   const MCObjectFileInfo::Environment Format =
     getContext().getObjectFileInfo()->getObjectFileType();
   bool IsMachO = Format == MCObjectFileInfo::IsMachO;
+  bool IsCOFF = Format == MCObjectFileInfo::IsCOFF;
 
   StringRef IDVal = DirectiveID.getIdentifier();
   if (IDVal == ".word")
@@ -8364,7 +8367,7 @@ bool ARMAsmParser::ParseDirective(AsmTok
   else if (IDVal == ".thumb_set")
     return parseDirectiveThumbSet(DirectiveID.getLoc());
 
-  if (!IsMachO) {
+  if (!IsMachO && !IsCOFF) {
     if (IDVal == ".arch")
       return parseDirectiveArch(DirectiveID.getLoc());
     else if (IDVal == ".cpu")

Added: llvm/trunk/test/MC/ARM/directive-unsupported.s
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/MC/ARM/directive-unsupported.s?rev=218014&view=auto
==============================================================================
--- llvm/trunk/test/MC/ARM/directive-unsupported.s (added)
+++ llvm/trunk/test/MC/ARM/directive-unsupported.s Wed Sep 17 23:28:29 2014
@@ -0,0 +1,68 @@
+@ RUN: not llvm-mc -triple thumbv7-windows -filetype asm -o /dev/null %s 2>&1 \
+@ RUN:     | FileCheck %s
+
+@ RUN: not llvm-mc -triple armv7-darwin -filetype asm -o /dev/null %s 2>&1 \
+@ RUN:    | FileCheck %s
+
+	.syntax unified
+
+	.arch armv7
+
+// CHECK: error: unknown directive
+// CHECK: .arch armv7
+// CHECK: ^
+
+	.cpu cortex-a7
+
+// CHECK: error: unknown directive
+// CHECK: .cpu cortex-a7
+// CHECK: ^
+
+	.fpu neon
+
+// CHECK: error: unknown directive
+// CHECK: .fpu neon
+// CHECK: ^
+
+	.eabi_attribute 0, 0
+
+// CHECK: error: unknown directive
+// CHECK: .eabi_attribute 0, 0
+// CHECK: ^
+
+	.inst 0xdefe
+
+// CHECK: error: unknown directive
+// CHECK: .inst 0xdefe
+// CHECK: ^
+
+	.inst.n 0xdefe
+
+// CHECK: error: unknown directive
+// CHECK: .inst.n 0xdefe
+// CHECK: ^
+
+	.inst.w 0xdefe
+
+// CHECK: error: unknown directive
+// CHECK: .inst.w 0xdefe
+// CHECK: ^
+
+	.object_arch armv7
+
+// CHECK: error: unknown directive
+// CHECK: .object_arch armv7
+// CHECK: ^
+
+	.tlsdescseq undefined
+
+// CHECK: error: unknown directive
+// CHECK: .tlsdescseq undefined
+// CHECK: ^
+
+	.fnstart
+
+// CHECK: error: unknown directive
+// CHECK: .fnstart
+// CHECK: ^
+