Make profile handle longjmps correctly

src/funcs.c

@@ -415,8 +415,8 @@ Obj STEVES_TRACING;
 #endif
 
 #define CHECK_RECURSION_BEFORE \
- CheckRecursionBefore(); \
- HookedLineIntoFunction(func);
+ HookedLineIntoFunction(func); \
+ CheckRecursionBefore();
 
 #define CHECK_RECURSION_AFTER \
  DecRecursionDepth(); \

src/profile.c

@@ -14,6 +14,7 @@
 #include "bool.h"
 #include "calls.h"
 #include "code.h"
+#include "funcs.h"
 #include "error.h"
 #include "hookintrprtr.h"
 #include "io.h"
@@ -95,7 +96,6 @@
 ** never marked as executed.
 */
 
-
 /****************************************************************************
 **
 ** Store the current state of the profiler
@@ -146,11 +146,56 @@ struct ProfileState
  ** clear */
  UInt profiledPreviously;
 
+ Int LongJmpOccurred;
+
+ // We store the value of RecursionDepth each time we enter a function.
+ // This is the only way to detect if GAP has left a function by performing
+ // a longjmp.
+ // We need to store the actual values, as RecursionDepth can increase
+ // by more than one when a GAP function is called
+ Obj visitedDepths;
 } profileState;
 
 /* We keep this seperate as it is exported for use in other files */
 UInt profileState_Active;
 
+
+static void ProfileRegisterLongJmpOccurred(void)
+{
+ profileState.LongJmpOccurred = 1;
+}
+
+// This function is called when we detect a longjmp occurred, and
+// outputs a 'return' into the profile for any function which was
+// jumped over.
+// It is fine for this function to be called when a longjmp has not
+// occurred, or when no function was longjmped over.
+static void CheckLeaveFunctionsAfterLongjmp(void)
+{
+ if (!profileState.LongJmpOccurred)
+ return;
+
+#ifdef HPCGAP
+ if (profileState.profiledThread != TLS(threadID))
+ return;
+#endif
+
+ profileState.LongJmpOccurred = 0;
+
+ Int pos = LEN_PLIST(profileState.visitedDepths);
+ Int depth = GetRecursionDepth();
+
+ while (pos > 0 && INT_INTOBJ(ELM_PLIST(profileState.visitedDepths, pos)) > depth) {
+ // Give dummy values if we do not know
+ fprintf(profileState.Stream,
+ "{\"Type\":\"O\",\"Fun\":\"nameless\",\"Line\":-1,"
+ "\"EndLine\":-1,\"File\":\"<missing filename>\","
+ "\"FileId\":-1}\n");
+ PopPlist(profileState.visitedDepths);
+ pos--;
+ }
+}
+
 static inline void outputFilenameIdIfRequired(UInt id)
 {
  if (id == 0) {
@@ -213,10 +258,32 @@ void HookedLineOutput(Obj func, char type)
 }
 
 void enterFunction(Obj func)
-{ HookedLineOutput(func, 'I'); }
+{
+#ifdef HPCGAP
+ if (profileState.profiledThread != TLS(threadID))
+ return;
+#endif
+ CheckLeaveFunctionsAfterLongjmp();
+ PushPlist(profileState.visitedDepths, INTOBJ_INT(GetRecursionDepth()));
+ HookedLineOutput(func, 'I');
+}
 
 void leaveFunction(Obj func)
-{ HookedLineOutput(func, 'O'); }
+{
+#ifdef HPCGAP
+ if (profileState.profiledThread != TLS(threadID))
+ return;
+#endif
+ // Do not crash if we exit the function in which
+ // Profile was originally called. The profiling
+ // package can handle such profiles.
+ if (LEN_PLIST(profileState.visitedDepths) > 0) {
+ PopPlist(profileState.visitedDepths);
+ }
+ CheckLeaveFunctionsAfterLongjmp();
+
+ HookedLineOutput(func, 'O');
+}
 
 /****************************************************************************
 **
@@ -306,6 +373,8 @@ static inline void outputStat(Stat stat, int exec, int visited)
  UInt line;
  int nameid;
 
+ CheckLeaveFunctionsAfterLongjmp();
+
  Int8 ticks = 0, newticks = 0;
 
  // Explicitly skip these two cases, as they are often specially handled
@@ -353,6 +422,7 @@ static inline void outputStat(Stat stat, int exec, int visited)
  profileState.minimumProfileTick;
  }
  ticks -= ticksDone;
+ outputFilenameIdIfRequired(nameid);
  fprintf(
  profileState.Stream,
  "{\"Type\":\"%c\",\"Ticks\":%d,\"Line\":%d,\"FileId\":%d}\n",
@@ -369,6 +439,7 @@ static inline void outputStat(Stat stat, int exec, int visited)
  }
  }
  else {
+ outputFilenameIdIfRequired(nameid);
  fprintf(profileState.Stream, "{\"Type\":\"%c\",\"Line\":%d,\"FileId\":%d}\n",
  exec ? 'E' : 'R', (int)line, (int)nameid);
  profileState.lastOutputted.line = line;
@@ -457,6 +528,7 @@ void enableAtStartup(char * filename, Int repeats, TickMethod tickMethod)
  ActivateHooks(&profileHooks);
 
  profileState_Active = 1;
+ RegisterSyLongjmpObserver(ProfileRegisterLongJmpOccurred);
  profileState.profiledPreviously = 1;
 #ifdef HPCGAP
  profileState.profiledThread = TLS(threadID);
@@ -518,7 +590,10 @@ Obj FuncACTIVATE_PROFILING(Obj self,
  return Fail;
  }
 
+ memset(&profileState, 0, sizeof(profileState));
+
  OutputtedFilenameList = NEW_PLIST(T_PLIST, 0);
+ profileState.visitedDepths = NEW_PLIST(T_PLIST, 0);
 
  if ( ! IsStringConv( filename ) ) {
  ErrorMayQuit("<filename> must be a string",0,0);
@@ -586,6 +661,7 @@ Obj FuncACTIVATE_PROFILING(Obj self,
  }
 
  profileState_Active = 1;
+ RegisterSyLongjmpObserver(ProfileRegisterLongJmpOccurred);
  profileState.profiledPreviously = 1;
 #ifdef HPCGAP
  profileState.profiledThread = TLS(threadID);
@@ -784,6 +860,7 @@ static Int InitLibrary (
  /* init filters and functions */
  InitGVarFuncsFromTable( GVarFuncs );
 
+ profileState.visitedDepths = NEW_PLIST(T_PLIST, 0);
  OutputtedFilenameList = NEW_PLIST(T_PLIST, 0);
  /* return success */
  return 0;
@@ -798,6 +875,7 @@ static Int InitKernel (
 {
  InitHdlrFuncsFromTable( GVarFuncs );
  InitGlobalBag(&OutputtedFilenameList, "src/profile.c:OutputtedFileList");
+ InitGlobalBag(&profileState.visitedDepths, "src/profile.c:visitedDepths");
  return 0;
 }
 

src/system.c

@@ -849,6 +849,8 @@ static void SySetInitialGapRootPaths(void)
 *F RegisterSyLongjmpObserver( <func> )
 ** Register a function to be called before longjmp is called.
 ** returns 1 on success, 0 if the table of functions is already full.
+** This function is idempotent -- if a function is passed multiple times
+** it is still only registered once.
 */
 
 enum { signalSyLongjmpFuncsLen = 16 };
@@ -859,6 +861,9 @@ Int RegisterSyLongjmpObserver(voidfunc func)
 {
  Int i;
  for (i = 0; i < signalSyLongjmpFuncsLen; ++i) {
+ if (signalSyLongjmpFuncs[i] == func) {
+ return 1;
+ }
  if (signalSyLongjmpFuncs[i] == 0) {
  signalSyLongjmpFuncs[i] = func;
  return 1;