VM profiler (#14833)

* Crude VM profiler

* Added --profileVM flag, refactoring

* fixed FileLine hash

* Use TLineInfo instead of own FileLine, updated formatting

* Refactoring, moved PStackFrame to vmdefs for cleaner data structure

* Moved vmprofiler to separate file

* Simplified TLineInfo hash, use toFileLineCol for output

* Hash

* Moved profile data into Config, dump only once at end of run

* Changed profile output header to show '#instr' instead of 'count'

* Do not accumulate instrcount for non-top frames

Co-authored-by: Ico Doornekamp <git@zevv.nl>

compiler/vmdef.nim

@@ -261,6 +261,21 @@ type
     config*: ConfigRef
     graph*: ModuleGraph
     oldErrorCount*: int
+    profiler*: Profiler
+
+  PStackFrame* = ref TStackFrame
+  TStackFrame* = object
+    prc*: PSym                 # current prc; proc that is evaluated
+    slots*: seq[TFullReg]      # parameters passed to the proc + locals;
+                              # parameters come first
+    next*: PStackFrame         # for stacking
+    comesFrom*: int
+    safePoints*: seq[int]      # used for exception handling
+                              # XXX 'break' should perform cleanup actions
+                              # What does the C backend do for it?
+  Profiler* = object
+    tEnter*: float
+    tos*: PStackFrame
 
   TPosition* = distinct int