[compiler-rt] Use SignalContext in ErrorStackOverflow and ErrorDeadlySignal

Summary: Part of https://github.com/google/sanitizers/issues/637

Reviewers: eugenis, alekseyshl, filcab

Subscribers: kubamracek, llvm-commits, dberris

Differential Revision: https://reviews.llvm.org/D37793

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@313168 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 50 insertions, 31 deletions

diff --git a/lib/sanitizer_common/sanitizer_common.h b/lib/sanitizer_common/sanitizer_common.h
index 32fd381cc..6cd21d79a 100644
--- a/lib/sanitizer_common/sanitizer_common.h
+++ b/lib/sanitizer_common/sanitizer_common.h
@@ -309,7 +309,6 @@ void SetSoftRssLimitExceededCallback(void (*Callback)(bool exceeded));
 typedef void (*SignalHandlerType)(int, void *, void *);
 HandleSignalMode GetHandleSignalMode(int signum);
 void InstallDeadlySignalHandlers(SignalHandlerType handler);
-const char *DescribeSignalOrException(int signo);
 // Signal reporting.
 void StartReportDeadlySignal();
 bool IsStackOverflow(const SignalContext &sig);
@@ -805,6 +804,9 @@ struct SignalContext {
 
   enum WriteFlag { UNKNOWN, READ, WRITE } write_flag;
 
+  // VS2013 doesn't implement unrestricted unions, so we need a trivial default
+  // constructor
+  SignalContext() = default;
   // SignalContext is going to keep pointers to siginfo and context without
   // owning them.
   SignalContext(void *siginfo, void *context, uptr addr, uptr pc, uptr sp,
@@ -830,7 +832,7 @@ struct SignalContext {
   int GetType() const;
 
   // String description of the signal.
-  const char *Describe() const { return DescribeSignalOrException(GetType()); }
+  const char *Describe() const;
 };
 
 void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp);
diff --git a/lib/sanitizer_common/sanitizer_fuchsia.cc b/lib/sanitizer_common/sanitizer_fuchsia.cc
index 7ea522a0d..07190f150 100644
--- a/lib/sanitizer_common/sanitizer_fuchsia.cc
+++ b/lib/sanitizer_common/sanitizer_fuchsia.cc
@@ -98,7 +98,7 @@ void InitTlsSize() {}
 void PrintModuleMap() {}
 
 void SignalContext::DumpAllRegisters(void *context) { UNIMPLEMENTED(); }
-const char *DescribeSignalOrException(int signo) { UNIMPLEMENTED(); }
+const char *SignalContext::Describe() const { UNIMPLEMENTED(); }
 
 struct UnwindTraceArg {
   BufferedStackTrace *stack;
diff --git a/lib/sanitizer_common/sanitizer_posix.cc b/lib/sanitizer_common/sanitizer_posix.cc
index b74b1f995..35fc35ce9 100644
--- a/lib/sanitizer_common/sanitizer_posix.cc
+++ b/lib/sanitizer_common/sanitizer_posix.cc
@@ -310,8 +310,8 @@ int SignalContext::GetType() const {
   return static_cast<const siginfo_t *>(siginfo)->si_signo;
 }
 
-const char *DescribeSignalOrException(int signo) {
-  switch (signo) {
+const char *SignalContext::Describe() const {
+  switch (GetType()) {
     case SIGFPE:
       return "FPE";
     case SIGILL:
diff --git a/lib/sanitizer_common/sanitizer_win.cc b/lib/sanitizer_common/sanitizer_win.cc
index 65898a709..65e7aa8d7 100644
--- a/lib/sanitizer_common/sanitizer_win.cc
+++ b/lib/sanitizer_common/sanitizer_win.cc
@@ -890,32 +890,6 @@ bool IsHandledDeadlyException(DWORD exceptionCode) {
   return false;
 }
 
-const char *DescribeSignalOrException(int signo) {
-  unsigned code = signo;
-  // Get the string description of the exception if this is a known deadly
-  // exception.
-  switch (code) {
-    case EXCEPTION_ACCESS_VIOLATION: return "access-violation";
-    case EXCEPTION_ARRAY_BOUNDS_EXCEEDED: return "array-bounds-exceeded";
-    case EXCEPTION_STACK_OVERFLOW: return "stack-overflow";
-    case EXCEPTION_DATATYPE_MISALIGNMENT: return "datatype-misalignment";
-    case EXCEPTION_IN_PAGE_ERROR: return "in-page-error";
-    case EXCEPTION_ILLEGAL_INSTRUCTION: return "illegal-instruction";
-    case EXCEPTION_PRIV_INSTRUCTION: return "priv-instruction";
-    case EXCEPTION_BREAKPOINT: return "breakpoint";
-    case EXCEPTION_FLT_DENORMAL_OPERAND: return "flt-denormal-operand";
-    case EXCEPTION_FLT_DIVIDE_BY_ZERO: return "flt-divide-by-zero";
-    case EXCEPTION_FLT_INEXACT_RESULT: return "flt-inexact-result";
-    case EXCEPTION_FLT_INVALID_OPERATION: return "flt-invalid-operation";
-    case EXCEPTION_FLT_OVERFLOW: return "flt-overflow";
-    case EXCEPTION_FLT_STACK_CHECK: return "flt-stack-check";
-    case EXCEPTION_FLT_UNDERFLOW: return "flt-underflow";
-    case EXCEPTION_INT_DIVIDE_BY_ZERO: return "int-divide-by-zero";
-    case EXCEPTION_INT_OVERFLOW: return "int-overflow";
-  }
-  return "unknown exception";
-}
-
 bool IsAccessibleMemoryRange(uptr beg, uptr size) {
   SYSTEM_INFO si;
   GetNativeSystemInfo(&si);
@@ -978,6 +952,49 @@ int SignalContext::GetType() const {
   return static_cast<const EXCEPTION_RECORD *>(siginfo)->ExceptionCode;
 }
 
+const char *SignalContext::Describe() const {
+  unsigned code = GetType();
+  // Get the string description of the exception if this is a known deadly
+  // exception.
+  switch (code) {
+    case EXCEPTION_ACCESS_VIOLATION:
+      return "access-violation";
+    case EXCEPTION_ARRAY_BOUNDS_EXCEEDED:
+      return "array-bounds-exceeded";
+    case EXCEPTION_STACK_OVERFLOW:
+      return "stack-overflow";
+    case EXCEPTION_DATATYPE_MISALIGNMENT:
+      return "datatype-misalignment";
+    case EXCEPTION_IN_PAGE_ERROR:
+      return "in-page-error";
+    case EXCEPTION_ILLEGAL_INSTRUCTION:
+      return "illegal-instruction";
+    case EXCEPTION_PRIV_INSTRUCTION:
+      return "priv-instruction";
+    case EXCEPTION_BREAKPOINT:
+      return "breakpoint";
+    case EXCEPTION_FLT_DENORMAL_OPERAND:
+      return "flt-denormal-operand";
+    case EXCEPTION_FLT_DIVIDE_BY_ZERO:
+      return "flt-divide-by-zero";
+    case EXCEPTION_FLT_INEXACT_RESULT:
+      return "flt-inexact-result";
+    case EXCEPTION_FLT_INVALID_OPERATION:
+      return "flt-invalid-operation";
+    case EXCEPTION_FLT_OVERFLOW:
+      return "flt-overflow";
+    case EXCEPTION_FLT_STACK_CHECK:
+      return "flt-stack-check";
+    case EXCEPTION_FLT_UNDERFLOW:
+      return "flt-underflow";
+    case EXCEPTION_INT_DIVIDE_BY_ZERO:
+      return "int-divide-by-zero";
+    case EXCEPTION_INT_OVERFLOW:
+      return "int-overflow";
+  }
+  return "unknown exception";
+}
+
 uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) {
   // FIXME: Actually implement this function.
   CHECK_GT(buf_len, 0);