Mercurial > cpython-lru_cache-weakref
diff Python/compile.c @ 56514:dc75d17dd304 legacy-trunk
Issue #1754094: Improve the stack depth calculation in the compiler.
There should be no other effect than a small decrease in memory use.
Patch by Christopher Tur Lesniewski-Laas.
| author | Neil Schemenauer <nascheme@enme.ucalgary.ca> |
|---|---|
| date | Wed, 14 Oct 2009 17:17:14 +0000 |
| parents | 917497e2509c |
| children | 2754d64180d1 |
line wrap: on
line diff
--- a/Python/compile.c Wed Oct 14 15:57:46 2009 +0000 +++ b/Python/compile.c Wed Oct 14 17:17:14 2009 +0000 @@ -692,13 +692,13 @@ return -1; case SLICE+0: - return 1; + return 0; case SLICE+1: - return 0; + return -1; case SLICE+2: - return 0; + return -1; case SLICE+3: - return -1; + return -2; case STORE_SLICE+0: return -2; @@ -778,7 +778,8 @@ case POP_BLOCK: return 0; case END_FINALLY: - return -1; /* or -2 or -3 if exception occurred */ + return -3; /* or -1 or -2 if no exception occurred or + return/break/continue */ case BUILD_CLASS: return -2; @@ -789,7 +790,7 @@ case UNPACK_SEQUENCE: return oparg-1; case FOR_ITER: - return 1; + return 1; /* or -1, at end of iterator */ case STORE_ATTR: return -2; @@ -815,7 +816,7 @@ case COMPARE_OP: return -1; case IMPORT_NAME: - return 0; + return -1; case IMPORT_FROM: return 1; @@ -835,10 +836,9 @@ case CONTINUE_LOOP: return 0; case SETUP_LOOP: - return 0; case SETUP_EXCEPT: case SETUP_FINALLY: - return 3; /* actually pushed by an exception */ + return 0; case LOAD_FAST: return 1; @@ -867,7 +867,7 @@ return -1; case MAKE_CLOSURE: - return -oparg; + return -oparg-1; case LOAD_CLOSURE: return 1; case LOAD_DEREF: @@ -3328,7 +3328,7 @@ static int stackdepth_walk(struct compiler *c, basicblock *b, int depth, int maxdepth) { - int i; + int i, target_depth; struct instr *instr; if (b->b_seen || b->b_startdepth >= depth) return maxdepth; @@ -3341,8 +3341,17 @@ maxdepth = depth; assert(depth >= 0); /* invalid code or bug in stackdepth() */ if (instr->i_jrel || instr->i_jabs) { + target_depth = depth; + if (instr->i_opcode == FOR_ITER) { + target_depth = depth-2; + } else if (instr->i_opcode == SETUP_FINALLY || + instr->i_opcode == SETUP_EXCEPT) { + target_depth = depth+3; + if (target_depth > maxdepth) + maxdepth = target_depth; + } maxdepth = stackdepth_walk(c, instr->i_target, - depth, maxdepth); + target_depth, maxdepth); if (instr->i_opcode == JUMP_ABSOLUTE || instr->i_opcode == JUMP_FORWARD) { goto out; /* remaining code is dead */
