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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218014 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp b/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
index 2243da03e28ab4b615d81a30bb1be318e6acc3f0..7e33ec5617df74eb5abba635d5d1c7233e22a761 100644 (file)
--- a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
+++ b/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
@@ -135,6 +135,8 @@ class ARMAsmParser : public MCTargetAsmParser {
   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(AsmToken DirectiveID) {
   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(AsmToken DirectiveID) {
   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")

diff --git a/test/MC/ARM/directive-unsupported.s b/test/MC/ARM/directive-unsupported.s
new file mode 100644 (file)
index 0000000..0b1f9ba
--- /dev/null
+++ b/test/MC/ARM/directive-unsupported.s
@@ -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: ^
+