Use BCOffset for DebugInfo

Summary:
It's using raw integers for bytecode offsets and indices, but it doesn't have
to.

Reviewed By: swtaarrs

Differential Revision: D56534784

fbshipit-source-id: 50f5ec68bc9514addf661c12ee5e72839e044159

cinderx/Jit/debug_info.cpp

@@ -135,7 +135,7 @@ void DebugInfo::addUnitCallStack(
     const jit::hir::FrameState* caller_frame_state) {
   uint16_t caller_id = getCallerID(caller_frame_state);
   uint16_t code_obj_id = getCodeObjID(code);
-  addr_locs_.emplace(addr, LocNode{code_obj_id, caller_id, bc_off.value()});
+  addr_locs_.emplace(addr, LocNode{code_obj_id, caller_id, bc_off});
 }
 
 uint16_t DebugInfo::getCodeObjID(BorrowedRef<PyCodeObject> code_obj) {
@@ -162,7 +162,7 @@ uint16_t DebugInfo::getCallerID(const jit::hir::FrameState* caller) {
   LocNode node{
       getCodeObjID(caller->code),
       getCallerID(caller->parent),
-      caller->instr_offset().value()};
+      caller->instr_offset()};
   for (uint16_t i = 0; i < inlined_calls_.size(); i++) {
     if (inlined_calls_[i] == node) {
       return i;

cinderx/Jit/debug_info.h

@@ -27,17 +27,18 @@ class Instr;
 // A location in a code object
 struct CodeObjLoc {
   CodeObjLoc(BorrowedRef<PyFrameObject> py_frame)
-      : code(py_frame->f_code),
-        instr_offset(py_frame->f_lasti * int{sizeof(_Py_CODEUNIT)}) {}
-  CodeObjLoc(BorrowedRef<PyCodeObject> code_, int lasti)
-      : code(code_), instr_offset(lasti) {}
+      : code{py_frame->f_code},
+        instr_offset{BCIndex{py_frame->f_lasti}.asOffset()} {}
+  CodeObjLoc(BorrowedRef<PyCodeObject> code, BCOffset instr_offset)
+      : code{code}, instr_offset{instr_offset} {}
+
   BorrowedRef<PyCodeObject> code;
 
   // Bytecode offset. A value less than 0 indicates the position is unknown.
-  int instr_offset{-1};
+  BCOffset instr_offset{-1};
 
   int lineNo() const {
-    return PyCode_Addr2Line(code, instr_offset);
+    return PyCode_Addr2Line(code, instr_offset.value());
   }
 };
 
@@ -86,7 +87,7 @@ class DebugInfo {
   // Given a node, the location information for its call stack is specified
   // by the node and the chain of inlined calls reachable from it.
   struct LocNode {
-    LocNode(uint16_t cobj_id, uint16_t clr_id, int bco)
+    LocNode(uint16_t cobj_id, uint16_t clr_id, BCOffset bco)
         : code_obj_id(cobj_id), caller_id(clr_id), bc_off(bco) {}
     // Index into code_objs of the PyCodeObject for this entry.
     uint16_t code_obj_id;
@@ -96,20 +97,14 @@ class DebugInfo {
     uint16_t caller_id;
 
     // Current bytecode offset.
-    int bc_off;
+    BCOffset bc_off;
 
     bool hasCaller() const {
       return caller_id != kNoCallerID;
     }
 
-    bool operator==(const LocNode& other) const {
-      return (code_obj_id == other.code_obj_id) &&
-          (caller_id == other.caller_id) && (bc_off == other.bc_off);
-    }
-
-    bool operator!=(const LocNode& other) const {
-      return !(*this == other);
-    }
+    bool operator==(const LocNode& other) const = default;
+    bool operator!=(const LocNode& other) const = default;
   };
 
   static const uint16_t kNoCallerID = UINT16_MAX;

cinderx/Jit/frame.cpp

@@ -248,7 +248,7 @@ PyFrameState getPyFrameStateForJITGen(PyGenObject* gen) {
 BorrowedRef<PyFrameObject> materializePyFrame(
     PyThreadState* tstate,
     _PyShadowFrame* shadow_frame,
-    int last_instr_offset,
+    BCOffset last_instr_offset,
     std::optional<BorrowedRef<PyFrameObject>> cursor) {
   // Make sure a PyFrameObject exists at the correct location in the call
   // stack.
@@ -276,7 +276,7 @@ BorrowedRef<PyFrameObject> materializePyFrame(
     }
   }
   // Update the PyFrameObject to refect the state of the JIT function
-  py_frame->f_lasti = last_instr_offset / sizeof(_Py_CODEUNIT);
+  py_frame->f_lasti = last_instr_offset.asIndex().value();
   if (is_shadow_frame_for_gen(shadow_frame)) {
     PyGenObject* gen = _PyShadowFrame_GetGen(shadow_frame);
     py_frame->f_state = getPyFrameStateForJITGen(gen);
@@ -411,7 +411,8 @@ UnitState getUnitState(_PyShadowFrame* shadow_frame) {
     JIT_DABORT("No debug info for addr {:x}", ip);
     for (std::size_t i = 0; i < unit_frames.size(); i++) {
       _PyShadowFrame* sf = unit_frames[i];
-      unit_state.emplace_back(sf, CodeObjLoc{_PyShadowFrame_GetCode(sf), -1});
+      unit_state.emplace_back(
+          sf, CodeObjLoc{_PyShadowFrame_GetCode(sf), BCOffset{-1}});
     }
   }