Skip to content

Commit

Permalink
Work on code generation for direct array and struct references
Browse files Browse the repository at this point in the history
  • Loading branch information
@positively-charged
positively-charged committed May 9, 2017
1 parent e055fa8 commit 5fb4612
Showing 1 changed file with 99 additions and 42 deletions.
141 changes: 99 additions & 42 deletions src/codegen/expr.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -7,6 +7,13 @@ enum { FIXEDNUMBER_WHOLE = 1 << 16 };
enum { NULLVALUE = 0 };
enum { EXTENDEDASPEC_STARTID = 256 };

enum result_description {
RESULTDESC_ARRAY,
RESULTDESC_REF,
RESULTDESC_STRUCT,
RESULTDESC_PRIMITIVE
};

struct result {
struct ref* ref;
struct structure* structure;
Expand All @@ -26,12 +33,16 @@ struct result {
bool skip_negate;
bool null;
bool safe;
bool direct;
};

static void init_result( struct result* result, bool push );
static enum result_description describe_result( struct result* result );
static void push_operand( struct codegen* codegen, struct node* node );
static void push_operand_result( struct codegen* codegen,
struct result* result, struct node* node );
static bool in_shared_array( struct codegen* codegen, struct result* result );
static bool has_dim_info( struct result* result );
static void push_initz( struct codegen* codegen, struct ref* ref,
struct node* initz );
static void visit_operand( struct codegen* codegen, struct result* result,
Expand Down Expand Up @@ -289,6 +300,22 @@ static void init_result( struct result* result, bool push ) {
result->skip_negate = false;
result->null = false;
result->safe = false;
result->direct = false;
}

static enum result_description describe_result( struct result* result ) {
if ( result->dim ) {
return RESULTDESC_ARRAY;
}
else if ( result->ref ) {
return RESULTDESC_REF;
}
else if ( result->structure ) {
return RESULTDESC_STRUCT;
}
else {
return RESULTDESC_PRIMITIVE;
}
}

static void push_operand( struct codegen* codegen, struct node* node ) {
Expand All @@ -300,31 +327,45 @@ static void push_operand( struct codegen* codegen, struct node* node ) {
static void push_operand_result( struct codegen* codegen,
struct result* result, struct node* node ) {
visit_operand( codegen, result, node );
if ( result->dim ) {
switch ( result->storage ) {
case STORAGE_MAP:
if ( result->diminfo_start > 0 ) {
switch ( describe_result( result ) ) {
case RESULTDESC_ARRAY:
if ( in_shared_array( codegen, result ) ) {
if ( has_dim_info( result ) ) {
c_pcd( codegen, PCD_PUSHNUMBER, result->diminfo_start );
c_update_dimtrack( codegen );
}
else {
}
else {
if ( result->status == R_NONE ) {
c_pcd( codegen, PCD_PUSHNUMBER, 0 );
result->status = R_ARRAYINDEX;
}
break;
case STORAGE_LOCAL:
case STORAGE_WORLD:
case STORAGE_GLOBAL:
}
break;
case RESULTDESC_STRUCT:
if ( result->status == R_NONE ) {
c_pcd( codegen, PCD_PUSHNUMBER, 0 );
result->status = R_ARRAYINDEX;
break;
default:
UNREACHABLE();
t_bail( codegen->task );
}
break;
case RESULTDESC_REF:
case RESULTDESC_PRIMITIVE:
break;
default:
UNREACHABLE();
t_bail( codegen->task );
}
}

static bool in_shared_array( struct codegen* codegen, struct result* result ) {
return ( codegen->shary.used && result->storage == STORAGE_MAP &&
result->index == codegen->shary.index );
}

static bool has_dim_info( struct result* result ) {
return ( result->diminfo_start > 0 );
}

static void push_initz( struct codegen* codegen, struct ref* ref,
struct node* initz ) {
struct result rside;
Expand Down Expand Up @@ -548,17 +589,23 @@ static void eq_ref( struct codegen* codegen, struct result* result,
}
else if ( ( lside.null && ! rside.null ) ||
( rside.null && ! lside.null ) ) {
// For array references (shared array offsets).
if ( ( lside.null && rside.diminfo_start > 0 ) ||
( rside.null && lside.diminfo_start > 0 ) ) {
c_pcd( codegen, ( binary->op == BOP_EQ ) ? PCD_EQ : PCD_NE );
// A direct array or struct reference is always valid. Depending on the
// operation, force a true or false result.
if ( ( lside.null && rside.direct ) || ( rside.null && lside.direct ) ) {
// Assume the equal operation here. Since a valid reference is not
// equal to null, we want false as the result here. Since one of the
// operands is null, which has a 0 value, executing PCD_ANDLOGICAL
// will give us a 0, regardless of the offset.
c_pcd( codegen, PCD_ANDLOGICAL );
// Negate the result of the equal operation to get the result for the
// not-equal operation. (`a != b` is the same as `! ( a == b )`.)
if ( binary->op == BOP_NEQ ) {
c_pcd( codegen, PCD_NEGATELOGICAL );
}
}
// For a direct array reference, the offset will be 0, which is the
// same as the null value. But an array is obviously not null. So use
// the PCD_ANDLOGICAL instruction to drop the two values off the stack
// and generate a 0 result (since both values are 0).
// For array references (shared array offsets).
else {
c_pcd( codegen, PCD_ANDLOGICAL );
c_pcd( codegen, ( binary->op == BOP_EQ ) ? PCD_EQ : PCD_NE );
}
}
else {
Expand Down Expand Up @@ -662,30 +709,29 @@ static void push_logical_operand( struct codegen* codegen,
// NOTE: Doesn't actually convert a value to 0 or 1. Should rename.
static void convert_to_boolean( struct codegen* codegen, struct result* result,
int spec ) {
if ( result->dim ) {
// For direct array references, the offset 0 will always be pushed.
// Negate the offset to produce a boolean true.
switch ( result->storage ) {
case STORAGE_MAP:
if ( result->diminfo_start == 0 ) {
c_pcd( codegen, PCD_NEGATELOGICAL );
}
break;
case STORAGE_LOCAL:
case STORAGE_WORLD:
case STORAGE_GLOBAL:
c_pcd( codegen, PCD_NEGATELOGICAL );
break;
default:
UNREACHABLE();
t_bail( codegen->task );
switch ( describe_result( result ) ) {
case RESULTDESC_ARRAY:
case RESULTDESC_STRUCT:
// A direct array or struct reference is always valid. Push a 1 and use
// the PCD_ORLOGICAL instruction to force a true result, regardless of
// what the offset might be. For an indirect reference, the offset will
// always be non-zero, so no additional code is necessary.
if ( result->direct ) {
c_pcd( codegen, PCD_PUSHNUMBER, 1 );
c_pcd( codegen, PCD_ORLOGICAL );
}
}
else if ( ! result->ref ) {
break;
case RESULTDESC_PRIMITIVE:
if ( spec == SPEC_STR ) {
c_pcd( codegen, PCD_PUSHNUMBER, 0 );
c_pcd( codegen, PCD_CALLFUNC, 2, EXTFUNC_GETCHAR );
}
break;
case RESULTDESC_REF:
break;
default:
UNREACHABLE();
t_bail( codegen->task );
}
}

Expand Down Expand Up @@ -1223,10 +1269,15 @@ static void subscript_array( struct codegen* codegen,
result->ref = lside->ref;
result->structure = lside->structure;
result->dim = lside->dim->next;
result->diminfo_start = lside->diminfo_start + 1;
// For an array that is passed by reference, move to the dimension
// information of the sub-array.
if ( has_dim_info( lside ) ) {
result->diminfo_start = lside->diminfo_start + 1;
}
result->storage = lside->storage;
result->index = lside->index;
result->status = R_ARRAYINDEX;
result->direct = lside->direct;
}
// Reference element.
else if ( lside->ref ) {
Expand All @@ -1252,6 +1303,7 @@ static void subscript_array( struct codegen* codegen,
result->storage = lside->storage;
result->index = lside->index;
result->status = R_ARRAYINDEX;
result->direct = lside->direct;
}
// Primitive element.
else {
Expand Down Expand Up @@ -1433,6 +1485,7 @@ static void access_structure_member( struct codegen* codegen,
result->storage = lside->storage;
result->index = lside->index;
result->status = R_ARRAYINDEX;
result->direct = lside->direct;
}
// Reference member.
else if ( member->ref ) {
Expand All @@ -1458,6 +1511,7 @@ static void access_structure_member( struct codegen* codegen,
result->storage = lside->storage;
result->index = lside->index;
result->status = R_ARRAYINDEX;
result->direct = lside->direct;
}
// Primitive member.
else {
Expand Down Expand Up @@ -1972,6 +2026,7 @@ static void visit_sure( struct codegen* codegen, struct result* result,
result->index = operand.index;
result->status = operand.status;
result->safe = true;
result->direct = operand.direct;
}

static void write_null_check( struct codegen* codegen ) {
Expand Down Expand Up @@ -2156,6 +2211,7 @@ static void visit_var( struct codegen* codegen, struct result* result,
result->storage = var->storage;
result->index = var->index;
}
result->direct = true;
}
// Reference variable.
else if ( var->ref ) {
Expand All @@ -2181,6 +2237,7 @@ static void visit_var( struct codegen* codegen, struct result* result,
result->storage = var->storage;
result->index = var->index;
}
result->direct = true;
}
// Primitive variable.
else {
Expand Down

0 comments on commit 5fb4612

Please sign in to comment.