It's not necessary to do rounding for alloca operations when the requested
alignment is equal to the stack alignment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40004 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/System/Unix/Signals.inc b/lib/System/Unix/Signals.inc
new file mode 100644
index 0000000..d1493a2
--- /dev/null
+++ b/lib/System/Unix/Signals.inc
@@ -0,0 +1,201 @@
+//===- Signals.cpp - Generic Unix Signals Implementation -----*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines some helpful functions for dealing with the possibility of
+// Unix signals occuring while your program is running.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Unix.h"
+#include <vector>
+#include <algorithm>
+#if HAVE_EXECINFO_H
+# include <execinfo.h> // For backtrace().
+#endif
+#if HAVE_SIGNAL_H
+#include <signal.h>
+#endif
+#if HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+using namespace llvm;
+
+namespace {
+
+bool StackTraceRequested = false;
+
+/// InterruptFunction - The function to call if ctrl-c is pressed.
+void (*InterruptFunction)() = 0;
+
+std::vector<sys::Path> *FilesToRemove = 0 ;
+std::vector<sys::Path> *DirectoriesToRemove = 0;
+
+// IntSigs - Signals that may interrupt the program at any time.
+const int IntSigs[] = {
+ SIGHUP, SIGINT, SIGQUIT, SIGPIPE, SIGTERM, SIGUSR1, SIGUSR2
+};
+const int *IntSigsEnd = IntSigs + sizeof(IntSigs)/sizeof(IntSigs[0]);
+
+// KillSigs - Signals that are synchronous with the program that will cause it
+// to die.
+const int KillSigs[] = {
+ SIGILL, SIGTRAP, SIGABRT, SIGFPE, SIGBUS, SIGSEGV, SIGSYS, SIGXCPU, SIGXFSZ
+#ifdef SIGEMT
+ , SIGEMT
+#endif
+};
+const int *KillSigsEnd = KillSigs + sizeof(KillSigs)/sizeof(KillSigs[0]);
+
+#ifdef HAVE_BACKTRACE
+void* StackTrace[256];
+#endif
+
+// PrintStackTrace - In the case of a program crash or fault, print out a stack
+// trace so that the user has an indication of why and where we died.
+//
+// On glibc systems we have the 'backtrace' function, which works nicely, but
+// doesn't demangle symbols. In order to backtrace symbols, we fork and exec a
+// 'c++filt' process to do the demangling. This seems like the simplest and
+// most robust solution when we can't allocate memory (such as in a signal
+// handler). If we can't find 'c++filt', we fallback to printing mangled names.
+//
+void PrintStackTrace() {
+#ifdef HAVE_BACKTRACE
+ // Use backtrace() to output a backtrace on Linux systems with glibc.
+ int depth = backtrace(StackTrace, sizeof(StackTrace)/sizeof(StackTrace[0]));
+
+ // Create a one-way unix pipe. The backtracing process writes to PipeFDs[1],
+ // the c++filt process reads from PipeFDs[0].
+ int PipeFDs[2];
+ if (pipe(PipeFDs)) {
+ backtrace_symbols_fd(StackTrace, depth, STDERR_FILENO);
+ return;
+ }
+
+ switch (pid_t ChildPID = fork()) {
+ case -1: // Error forking, print mangled stack trace
+ close(PipeFDs[0]);
+ close(PipeFDs[1]);
+ backtrace_symbols_fd(StackTrace, depth, STDERR_FILENO);
+ return;
+ default: // backtracing process
+ close(PipeFDs[0]); // Close the reader side.
+
+ // Print the mangled backtrace into the pipe.
+ backtrace_symbols_fd(StackTrace, depth, PipeFDs[1]);
+ close(PipeFDs[1]); // We are done writing.
+ while (waitpid(ChildPID, 0, 0) == -1)
+ if (errno != EINTR) break;
+ return;
+
+ case 0: // c++filt process
+ close(PipeFDs[1]); // Close the writer side.
+ dup2(PipeFDs[0], 0); // Read from standard input
+ close(PipeFDs[0]); // Close the old descriptor
+ dup2(2, 1); // Revector stdout -> stderr
+
+ // Try to run c++filt or gc++filt. If neither is found, call back on 'cat'
+ // to print the mangled stack trace. If we can't find cat, just exit.
+ execlp("c++filt", "c++filt", (char*)NULL);
+ execlp("gc++filt", "gc++filt", (char*)NULL);
+ execlp("cat", "cat", (char*)NULL);
+ execlp("/bin/cat", "cat", (char*)NULL);
+ exit(0);
+ }
+#endif
+}
+
+// SignalHandler - The signal handler that runs...
+RETSIGTYPE SignalHandler(int Sig) {
+ if (FilesToRemove != 0)
+ while (!FilesToRemove->empty()) {
+ FilesToRemove->back().eraseFromDisk(true);
+ FilesToRemove->pop_back();
+ }
+
+ if (DirectoriesToRemove != 0)
+ while (!DirectoriesToRemove->empty()) {
+ DirectoriesToRemove->back().eraseFromDisk(true);
+ DirectoriesToRemove->pop_back();
+ }
+
+ if (std::find(IntSigs, IntSigsEnd, Sig) != IntSigsEnd) {
+ if (InterruptFunction) {
+ void (*IF)() = InterruptFunction;
+ InterruptFunction = 0;
+ IF(); // run the interrupt function.
+ return;
+ } else {
+ exit(1); // If this is an interrupt signal, exit the program
+ }
+ }
+
+ // Otherwise if it is a fault (like SEGV) output the stacktrace to
+ // STDERR (if we can) and reissue the signal to die...
+ if (StackTraceRequested)
+ PrintStackTrace();
+ signal(Sig, SIG_DFL);
+}
+
+// Just call signal
+void RegisterHandler(int Signal) {
+ signal(Signal, SignalHandler);
+}
+
+}
+
+
+void sys::SetInterruptFunction(void (*IF)()) {
+ InterruptFunction = IF;
+ RegisterHandler(SIGINT);
+}
+
+// RemoveFileOnSignal - The public API
+bool sys::RemoveFileOnSignal(const sys::Path &Filename, std::string* ErrMsg) {
+ if (FilesToRemove == 0)
+ FilesToRemove = new std::vector<sys::Path>;
+
+ FilesToRemove->push_back(Filename);
+
+ std::for_each(IntSigs, IntSigsEnd, RegisterHandler);
+ std::for_each(KillSigs, KillSigsEnd, RegisterHandler);
+ return false;
+}
+
+// RemoveDirectoryOnSignal - The public API
+bool sys::RemoveDirectoryOnSignal(const sys::Path& path, std::string* ErrMsg) {
+ // Not a directory?
+ struct stat buf;
+ if (0 != stat(path.c_str(), &buf)) {
+ MakeErrMsg(ErrMsg, path.toString() + ": can't get status of file");
+ return true;
+ }
+
+ if (!S_ISDIR(buf.st_mode)) {
+ if (ErrMsg)
+ *ErrMsg = path.toString() + " is not a directory";
+ return true;
+ }
+
+ if (DirectoriesToRemove == 0)
+ DirectoriesToRemove = new std::vector<sys::Path>;
+
+ DirectoriesToRemove->push_back(path);
+
+ std::for_each(IntSigs, IntSigsEnd, RegisterHandler);
+ std::for_each(KillSigs, KillSigsEnd, RegisterHandler);
+ return false;
+}
+
+/// PrintStackTraceOnErrorSignal - When an error signal (such as SIBABRT or
+/// SIGSEGV) is delivered to the process, print a stack trace and then exit.
+void sys::PrintStackTraceOnErrorSignal() {
+ StackTraceRequested = true;
+ std::for_each(KillSigs, KillSigsEnd, RegisterHandler);
+}