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;