3 # Copyright (c) 1996 Malcolm Beattie
5 # You may distribute under the terms of either the GNU General Public
6 # License or the Artistic License, as specified in the README file.
11 @EXPORT_OK = qw(set_callback T_UNKNOWN T_DOUBLE T_INT VALID_UNSIGNED
12 VALID_INT VALID_DOUBLE VALID_SV REGISTER TEMPORARY);
13 %EXPORT_TAGS = (types => [qw(T_UNKNOWN T_DOUBLE T_INT)],
14 flags => [qw(VALID_INT VALID_DOUBLE VALID_SV
15 VALID_UNSIGNED REGISTER TEMPORARY)]);
19 use B qw(class SVf_IOK SVf_NOK SVf_IVisUV);
22 sub T_UNKNOWN () { 0 }
25 sub T_SPECIAL () { 3 }
28 sub VALID_INT () { 0x01 }
29 sub VALID_UNSIGNED () { 0x02 }
30 sub VALID_DOUBLE () { 0x04 }
31 sub VALID_SV () { 0x08 }
32 sub REGISTER () { 0x10 } # no implicit write-back when calling subs
33 sub TEMPORARY () { 0x20 } # no implicit write-back needed at all
34 sub SAVE_INT () { 0x40 } #if int part needs to be saved at all
35 sub SAVE_DOUBLE () { 0x80 } #if double part needs to be saved at all
39 # Callback for runtime code generation
41 my $runtime_callback = sub { confess "set_callback not yet called" };
42 sub set_callback (&) { $runtime_callback = shift }
43 sub runtime { &$runtime_callback(@_) }
49 sub write_back { confess "stack object does not implement write_back" }
51 sub invalidate { shift->{flags} &= ~(VALID_INT |VALID_UNSIGNED | VALID_DOUBLE) }
55 if (!($obj->{flags} & VALID_SV)) {
57 $obj->{flags} |= VALID_SV;
64 if (!($obj->{flags} & VALID_INT)) {
66 $obj->{flags} |= VALID_INT|SAVE_INT;
73 if (!($obj->{flags} & VALID_DOUBLE)) {
75 $obj->{flags} |= VALID_DOUBLE|SAVE_DOUBLE;
82 return $obj->{type} == T_INT ? $obj->as_int : $obj->as_double;
87 if ($obj->{flags} & VALID_INT ){
90 if ($obj->{flags} & VALID_DOUBLE ){
93 return sprintf("(SvTRUE(%s))", $obj->as_sv) ;
101 my $type = $obj->{type};
102 my $flags = $obj->{flags};
104 if ($type == T_UNKNOWN) {
106 } elsif ($type == T_INT) {
108 } elsif ($type == T_DOUBLE) {
111 $type = "(illegal type $type)";
113 push(@flags, "VALID_INT") if $flags & VALID_INT;
114 push(@flags, "VALID_DOUBLE") if $flags & VALID_DOUBLE;
115 push(@flags, "VALID_SV") if $flags & VALID_SV;
116 push(@flags, "REGISTER") if $flags & REGISTER;
117 push(@flags, "TEMPORARY") if $flags & TEMPORARY;
118 @flags = ("none") unless @flags;
119 return sprintf("%s type=$type flags=%s sv=$obj->{sv}",
120 class($obj), join("|", @flags));
125 my $type = $obj->{type};
126 my $flags = $obj->{flags};
127 if ($type == T_INT || $flags & VALID_INT) {
129 } elsif ($type == T_DOUBLE || $flags & VALID_DOUBLE) {
137 # Caller needs to ensure that set_int, set_double,
138 # set_numeric and set_sv are only invoked on legal lvalues.
141 my ($obj, $expr,$unsigned) = @_;
142 runtime("$obj->{iv} = $expr;");
143 $obj->{flags} &= ~(VALID_SV | VALID_DOUBLE);
144 $obj->{flags} |= VALID_INT|SAVE_INT;
145 $obj->{flags} |= VALID_UNSIGNED if $unsigned;
149 my ($obj, $expr) = @_;
150 runtime("$obj->{nv} = $expr;");
151 $obj->{flags} &= ~(VALID_SV | VALID_INT);
152 $obj->{flags} |= VALID_DOUBLE|SAVE_DOUBLE;
156 my ($obj, $expr) = @_;
157 if ($obj->{type} == T_INT) {
158 $obj->set_int($expr);
160 $obj->set_double($expr);
165 my ($obj, $expr) = @_;
166 runtime("SvSetSV($obj->{sv}, $expr);");
168 $obj->{flags} |= VALID_SV;
175 @B::Stackobj::Padsv::ISA = 'B::Stackobj';
176 sub B::Stackobj::Padsv::new {
177 my ($class, $type, $extra_flags, $ix, $iname, $dname) = @_;
178 $extra_flags |= SAVE_INT if $extra_flags & VALID_INT;
179 $extra_flags |= SAVE_DOUBLE if $extra_flags & VALID_DOUBLE;
182 flags => VALID_SV | $extra_flags,
183 sv => "PL_curpad[$ix]",
189 sub B::Stackobj::Padsv::load_int {
191 if ($obj->{flags} & VALID_DOUBLE) {
192 runtime("$obj->{iv} = $obj->{nv};");
194 runtime("$obj->{iv} = SvIV($obj->{sv});");
196 $obj->{flags} |= VALID_INT|SAVE_INT;
199 sub B::Stackobj::Padsv::load_double {
202 runtime("$obj->{nv} = SvNV($obj->{sv});");
203 $obj->{flags} |= VALID_DOUBLE|SAVE_DOUBLE;
205 sub B::Stackobj::Padsv::save_int {
207 return $obj->{flags} & SAVE_INT;
210 sub B::Stackobj::Padsv::save_double {
212 return $obj->{flags} & SAVE_DOUBLE;
215 sub B::Stackobj::Padsv::write_back {
217 my $flags = $obj->{flags};
218 return if $flags & VALID_SV;
219 if ($flags & VALID_INT) {
220 if ($flags & VALID_UNSIGNED ){
221 runtime("sv_setuv($obj->{sv}, $obj->{iv});");
223 runtime("sv_setiv($obj->{sv}, $obj->{iv});");
225 } elsif ($flags & VALID_DOUBLE) {
226 runtime("sv_setnv($obj->{sv}, $obj->{nv});");
228 confess "write_back failed for lexical @{[$obj->peek]}\n";
230 $obj->{flags} |= VALID_SV;
237 @B::Stackobj::Const::ISA = 'B::Stackobj';
238 sub B::Stackobj::Const::new {
239 my ($class, $sv) = @_;
242 sv => $sv # holds the SV object until write_back happens
244 if ( ref($sv) eq "B::SPECIAL" ){
245 $obj->{type}= T_SPECIAL;
247 my $svflags = $sv->FLAGS;
248 if ($svflags & SVf_IOK) {
249 $obj->{flags} = VALID_INT|VALID_DOUBLE;
250 $obj->{type} = T_INT;
251 if ($svflags & SVf_IVisUV){
252 $obj->{flags} |= VALID_UNSIGNED;
253 $obj->{nv} = $obj->{iv} = $sv->UVX;
255 $obj->{nv} = $obj->{iv} = $sv->IV;
257 } elsif ($svflags & SVf_NOK) {
258 $obj->{flags} = VALID_INT|VALID_DOUBLE;
259 $obj->{type} = T_DOUBLE;
260 $obj->{iv} = $obj->{nv} = $sv->NV;
262 $obj->{type} = T_UNKNOWN;
268 sub B::Stackobj::Const::write_back {
270 return if $obj->{flags} & VALID_SV;
271 # Save the SV object and replace $obj->{sv} by its C source code name
272 $obj->{sv} = $obj->{sv}->save;
273 $obj->{flags} |= VALID_SV|VALID_INT|VALID_DOUBLE;
276 sub B::Stackobj::Const::load_int {
278 if (ref($obj->{sv}) eq "B::RV"){
279 $obj->{iv} = int($obj->{sv}->RV->PV);
281 $obj->{iv} = int($obj->{sv}->PV);
283 $obj->{flags} |= VALID_INT;
286 sub B::Stackobj::Const::load_double {
288 if (ref($obj->{sv}) eq "B::RV"){
289 $obj->{nv} = $obj->{sv}->RV->PV + 0.0;
291 $obj->{nv} = $obj->{sv}->PV + 0.0;
293 $obj->{flags} |= VALID_DOUBLE;
296 sub B::Stackobj::Const::invalidate {}
302 @B::Stackobj::Bool::ISA = 'B::Stackobj';
303 sub B::Stackobj::Bool::new {
304 my ($class, $preg) = @_;
307 flags => VALID_INT|VALID_DOUBLE,
310 preg => $preg # this holds our ref to the pseudo-reg
315 sub B::Stackobj::Bool::write_back {
317 return if $obj->{flags} & VALID_SV;
318 $obj->{sv} = "($obj->{iv} ? &PL_sv_yes : &PL_sv_no)";
319 $obj->{flags} |= VALID_SV;
322 # XXX Might want to handle as_double/set_double/load_double?
324 sub B::Stackobj::Bool::invalidate {}
332 B::Stackobj - Helper module for CC backend
344 Malcolm Beattie, C<mbeattie@sable.ox.ac.uk>