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Fail when using negative constants if not allowed
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Some commands, such as `DS`, `BANK[n]`, etc, don't allow the use of
negative constants, but there wasn't any check to prohibit the code from
trying to do so.

This patch adds the `uconst` type to the parser to use when a constant
is expected, but it mustn't be negative.

Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>
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@AntonioND
AntonioND committed Jul 1, 2017
1 parent bb12806 commit fe65e07
Showing 1 changed file with 23 additions and 14 deletions.
37 changes: 23 additions & 14 deletions src/asm/asmy.y
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Original file line number Diff line number Diff line change
Expand Up @@ -439,6 +439,7 @@ void if_skip_to_endc( void )

%type <sVal> relocconst
%type <nConstValue> const
%type <nConstValue> uconst
%type <nConstValue> const_3bit
%type <sVal> const_8bit
%type <sVal> const_16bit
Expand Down Expand Up @@ -692,7 +693,7 @@ shift : T_POP_SHIFT
{ sym_ShiftCurrentMacroArgs(); }
;

rept : T_POP_REPT const
rept : T_POP_REPT uconst
{
copyrept();
fstk_RunRept( $2 );
Expand All @@ -710,36 +711,36 @@ equs : T_LABEL T_POP_EQUS string
{ sym_AddString( $1, $3 ); }
;

rsset : T_POP_RSSET const
rsset : T_POP_RSSET uconst
{ sym_AddSet( "_RS", $2 ); }
;

rsreset : T_POP_RSRESET
{ sym_AddSet( "_RS", 0 ); }
;

rl : T_LABEL T_POP_RL const
rl : T_LABEL T_POP_RL uconst
{
sym_AddEqu( $1, sym_GetConstantValue("_RS") );
sym_AddSet( "_RS", sym_GetConstantValue("_RS")+4*$3 );
}
;

rw : T_LABEL T_POP_RW const
rw : T_LABEL T_POP_RW uconst
{
sym_AddEqu( $1, sym_GetConstantValue("_RS") );
sym_AddSet( "_RS", sym_GetConstantValue("_RS")+2*$3 );
}
;

rb : T_LABEL T_POP_RB const
rb : T_LABEL T_POP_RB uconst
{
sym_AddEqu( $1, sym_GetConstantValue("_RS") );
sym_AddSet( "_RS", sym_GetConstantValue("_RS")+$3 );
}
;

ds : T_POP_DS const
ds : T_POP_DS uconst
{ out_Skip( $2 ); }
;

Expand Down Expand Up @@ -821,7 +822,7 @@ include : T_POP_INCLUDE string

incbin : T_POP_INCBIN string
{ out_BinaryFile( $2 ); }
| T_POP_INCBIN string ',' const ',' const
| T_POP_INCBIN string ',' uconst ',' uconst
{
out_BinaryFileSlice( $2, $4, $6 );
}
Expand Down Expand Up @@ -1042,6 +1043,14 @@ relocconst : T_ID
{ $$ = $2; }
;

uconst : const
{
if($1 < 0)
fatalerror("Constant mustn't be negative: %d", $1);
$$=$1;
}
;

const : T_ID { $$ = sym_GetConstantValue($1); }
| T_NUMBER { $$ = $1; }
| string { $$ = str2int($1); }
Expand Down Expand Up @@ -1115,7 +1124,7 @@ const : T_ID { $$ = sym_GetConstantValue($1); }

string : T_STRING
{ strcpy($$,$1); }
| T_OP_STRSUB '(' string ',' const ',' const ')'
| T_OP_STRSUB '(' string ',' uconst ',' uconst ')'
{ strncpy($$,$3+$5-1,$7); $$[$7]=0; }
| T_OP_STRCAT '(' string ',' string ')'
{ strcpy($$,$3); strcat($$,$5); }
Expand All @@ -1129,33 +1138,33 @@ section:
{
out_NewSection($2,$4);
}
| T_POP_SECTION string ',' sectiontype '[' const ']'
| T_POP_SECTION string ',' sectiontype '[' uconst ']'
{
if( $6>=0 && $6<0x10000 )
out_NewAbsSection($2,$4,$6,-1);
else
yyerror("Address $%x not 16-bit", $6);
}
| T_POP_SECTION string ',' sectiontype ',' T_OP_ALIGN '[' const ']'
| T_POP_SECTION string ',' sectiontype ',' T_OP_ALIGN '[' uconst ']'
{
out_NewAlignedSection($2, $4, $8, -1);
}
| T_POP_SECTION string ',' sectiontype ',' T_OP_BANK '[' const ']'
| T_POP_SECTION string ',' sectiontype ',' T_OP_BANK '[' uconst ']'
{
bankrangecheck($2, $4, -1, $8);
}
| T_POP_SECTION string ',' sectiontype '[' const ']' ',' T_OP_BANK '[' const ']'
| T_POP_SECTION string ',' sectiontype '[' uconst ']' ',' T_OP_BANK '[' uconst ']'
{
if ($6 < 0 || $6 > 0x10000) {
yyerror("Address $%x not 16-bit", $6);
}
bankrangecheck($2, $4, $6, $11);
}
| T_POP_SECTION string ',' sectiontype ',' T_OP_ALIGN '[' const ']' ',' T_OP_BANK '[' const ']'
| T_POP_SECTION string ',' sectiontype ',' T_OP_ALIGN '[' uconst ']' ',' T_OP_BANK '[' uconst ']'
{
out_NewAlignedSection($2, $4, $8, $13);
}
| T_POP_SECTION string ',' sectiontype ',' T_OP_BANK '[' const ']' ',' T_OP_ALIGN '[' const ']'
| T_POP_SECTION string ',' sectiontype ',' T_OP_BANK '[' uconst ']' ',' T_OP_ALIGN '[' uconst ']'
{
out_NewAlignedSection($2, $4, $13, $8);
}
Expand Down

1 comment on commit fe65e07

@meithecatte
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ds with a negative value was useful. That way you could use an area of memory multiple times easily. You could interleave the labels but sometimes types and structs make it hard.

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