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enhanced compile_while_expression()/compile_do_while_expression() not to eliminate blocks containing one or more labels

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hyunghwan.chung
2019-08-07 08:34:53 +00:00
parent 3e1aded8a8
commit bb41dc5486
2 changed files with 84 additions and 8 deletions
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16
moo/lib/comp.c
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@ -6462,6 +6462,7 @@ static int compile_while_expression (moo_t* moo) /* or compile_until_expression
moo_ioloc_t while_loc, brace_loc, closing_brace_loc;
moo_oow_t precondpos, postcondpos, prebbpos, postbbpos;
int cond_style = 0, loop_pushed = 0, is_until_loop;
moo_label_t* la, * lb;
MOO_ASSERT (moo, TOKEN_TYPE(moo) == MOO_IOTOK_WHILE || TOKEN_TYPE(moo) == MOO_IOTOK_UNTIL);
@ -6521,12 +6522,14 @@ static int compile_while_expression (moo_t* moo) /* or compile_until_expression
GET_TOKEN (moo); /* get { */
brace_loc = *TOKEN_LOC(moo);
prebbpos = cc->mth.code.len;
la = cc->mth._label;
if (compile_braced_block(moo) <= -1) goto oops;
lb = cc->mth._label;
closing_brace_loc = *TOKEN_LOC(moo);
GET_TOKEN (moo); /* get the next token after } */
postbbpos = cc->mth.code.len;
if (prebbpos + 1 == postbbpos && cc->mth.code.ptr[prebbpos] == BCODE_PUSH_NIL)
if (la == lb && prebbpos + 1 == postbbpos && cc->mth.code.ptr[prebbpos] == BCODE_PUSH_NIL)
{
/* optimization -
* the braced block is kind of empty as it only pushes nil.
@ -6560,7 +6563,7 @@ static int compile_while_expression (moo_t* moo) /* or compile_until_expression
}
}
if (cond_style == -1)
if (la == lb && cond_style == -1)
{
/* optimization - get rid of instructions generated for the while
* loop including the conditional as the condition was false */
@ -6591,6 +6594,7 @@ static int compile_do_while_expression (moo_t* moo)
moo_oow_t precondpos, postcondpos, prebbpos, postbbpos;
int jbinst = 0, loop_pushed = 0, is_until_loop;
moo_loop_t* loop = MOO_NULL;
moo_label_t* la, * lb;
MOO_ASSERT (moo, TOKEN_TYPE(moo) == MOO_IOTOK_DO);
do_loc = *TOKEN_LOC(moo);
@ -6603,7 +6607,9 @@ static int compile_do_while_expression (moo_t* moo)
if (push_loop(moo, MOO_LOOP_DO_WHILE, prebbpos) <= -1) goto oops;
loop_pushed = 1;
la = cc->mth._label;
if (compile_braced_block(moo) <= -1) goto oops;
lb = cc->mth._label;
closing_brace_loc = *TOKEN_LOC(moo);
GET_TOKEN (moo); /* get the next token after } */
@ -6617,7 +6623,7 @@ static int compile_do_while_expression (moo_t* moo)
GET_TOKEN (moo); /* get ( */
postbbpos = cc->mth.code.len;
if (prebbpos + 1 == postbbpos && cc->mth.code.ptr[prebbpos] == BCODE_PUSH_NIL)
if (la == lb && prebbpos + 1 == postbbpos && cc->mth.code.ptr[prebbpos] == BCODE_PUSH_NIL)
{
/* optimization -
* the braced block is kind of empty as it only pushes nil.
@ -6651,14 +6657,14 @@ static int compile_do_while_expression (moo_t* moo)
if (cc->mth.code.ptr[precondpos] == (is_until_loop? BCODE_PUSH_FALSE: BCODE_PUSH_TRUE))
{
/* the conditional is always true. eliminate PUSH_TRUE and emit an absolute jump */
eliminate_instructions (moo, precondpos, cc->mth.code.len - 1);
eliminate_instructions (moo, precondpos, precondpos);
postcondpos = precondpos;
jbinst = BCODE_JUMP_BACKWARD;
}
else if (cc->mth.code.ptr[precondpos] == (is_until_loop? BCODE_PUSH_TRUE: BCODE_PUSH_FALSE))
{
/* the conditional is always false. eliminate PUSH_FALSE and don't emit jump */
eliminate_instructions (moo, precondpos, cc->mth.code.len - 1);
eliminate_instructions (moo, precondpos, precondpos);
postcondpos = precondpos;
goto skip_emitting_jump_backward;
}