py: Implement break and continue byte codes, and add tests.

Also fixes a bug in the for-in-range optimiser.

I hope to remove break and continue byte codes in the future and just
use jump (if possible).
This commit is contained in:
Damien George 2014-01-21 23:48:04 +00:00
parent 2c30256382
commit 600ae734cf
4 changed files with 47 additions and 3 deletions

View File

@ -1442,24 +1442,27 @@ void compile_for_stmt_optimised_range(compiler_t *comp, mp_parse_node_t pn_var,
comp->continue_label = continue_label;
int top_label = comp_next_label(comp);
int entry_label = comp_next_label(comp);
// compile: var = start
compile_node(comp, pn_start);
c_assign(comp, pn_var, ASSIGN_STORE);
EMIT(jump, continue_label);
EMIT(jump, entry_label);
EMIT(label_assign, top_label);
// compile body
compile_node(comp, pn_body);
EMIT(label_assign, continue_label);
// compile: var += step
c_assign(comp, pn_var, ASSIGN_AUG_LOAD);
compile_node(comp, pn_step);
EMIT(binary_op, RT_BINARY_OP_INPLACE_ADD);
c_assign(comp, pn_var, ASSIGN_AUG_STORE);
EMIT(label_assign, continue_label);
EMIT(label_assign, entry_label);
// compile: if var <cond> end: goto top
compile_node(comp, pn_var);

14
py/vm.c
View File

@ -326,6 +326,18 @@ bool mp_execute_byte_code_2(const byte *code_info, const byte **ip_in_out, mp_ob
break;
*/
// TODO this might need more sophisticated handling when breaking from within an except
case MP_BC_BREAK_LOOP:
DECODE_ULABEL;
ip += unum;
break;
// TODO this might need more sophisticated handling when breaking from within an except
case MP_BC_CONTINUE_LOOP:
DECODE_ULABEL;
ip += unum;
break;
// matched against: POP_BLOCK or POP_EXCEPT (anything else?)
case MP_BC_SETUP_EXCEPT:
DECODE_ULABEL; // except labels are always forward
@ -366,7 +378,7 @@ bool mp_execute_byte_code_2(const byte *code_info, const byte **ip_in_out, mp_ob
exc_sp -= 2; // pop back to previous exception handler
break;
// matched againts: SETUP_EXCEPT
// matched against: SETUP_EXCEPT
case MP_BC_POP_EXCEPT:
// TODO need to work out how blocks work etc
// pops block, checks it's an exception block, and restores the stack, saving the 3 exception values to local threadstate

13
tests/basics/break.py Normal file
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@ -0,0 +1,13 @@
while True:
break
for i in range(4):
print('one', i)
if i > 2:
break
print('two', i)
for i in [1, 2, 3, 4]:
if i == 3:
break
print(i)

16
tests/basics/continue.py Normal file
View File

@ -0,0 +1,16 @@
for i in range(4):
print('one', i)
if i > 2:
continue
print('two', i)
for i in range(4):
print('one', i)
if i < 2:
continue
print('two', i)
for i in [1, 2, 3, 4]:
if i == 3:
continue
print(i)