6502/cc65
1
0
Fork 0
mirror of https://github.com/cc65/cc65.git synced 2024-12-24 11:31:31 +00:00
Code Issues Projects Releases Wiki Activity
5e7c7d78fc
cc65/cfg/c64-overlay.cfg

85 lines
4.8 KiB
INI
Raw Normal View History

Adapted, to the c64 target, the INIT-segment overlay scheme from the apple2 targets. When a program starts running, INIT is moved from one place to another place. Then, INIT's code is executed; and, the first place is re-used for variables. After the INIT code has finished, the second place can be re-used by the heap and the C stack. That means that initiation code and data won't waste any RAM space after they stop being needed.
2015-10-05 09:47:43 +00:00
FEATURES {
Reduced c64-overlay.cfg's size by factoring out a different common expression.
2015-10-08 10:11:37 +00:00
STARTADDRESS: default = $0801;
Adapted, to the c64 target, the INIT-segment overlay scheme from the apple2 targets. When a program starts running, INIT is moved from one place to another place. Then, INIT's code is executed; and, the first place is re-used for variables. After the INIT code has finished, the second place can be re-used by the heap and the C stack. That means that initiation code and data won't waste any RAM space after they stop being needed.
2015-10-05 09:47:43 +00:00
}
Added secondary linker config for C64 overlays (incl. demo program). git-svn-id: svn://svn.cc65.org/cc65/trunk@5679 b7a2c559-68d2-44c3-8de9-860c34a00d81
2012-06-03 16:16:11 +00:00
SYMBOLS {
Reduced c64-overlay.cfg's size by factoring out a different common expression.
2015-10-08 10:11:37 +00:00
__LOADADDR__: type = import;
__EXEHDR__: type = import;
__OVERLAYADDR__: type = import;
__STACKSIZE__: type = weak, value = $0800; # 2k stack
__OVERLAYSIZE__: type = weak, value = $1000; # 4k overlay
__HIMEM__: type = weak, value = $D000;
__OVERLAYSTART__: type = export, value = __HIMEM__ - __OVERLAYSIZE__;
Added secondary linker config for C64 overlays (incl. demo program). git-svn-id: svn://svn.cc65.org/cc65/trunk@5679 b7a2c559-68d2-44c3-8de9-860c34a00d81
2012-06-03 16:16:11 +00:00
}
MEMORY {
Reduced c64-overlay.cfg's size by factoring out a different common expression.
2015-10-08 10:11:37 +00:00
ZP: file = "", define = yes, start = $0002, size = $001A;
LOADADDR: file = %O, start = %S - 2, size = $0002;
HEADER: file = %O, define = yes, start = %S, size = $000D;
Changed run location of INIT segment. So far the INIT segment was run from the later heap+stack. Now the INIT segment is run from the later BSS. The background is that so far the INIT segment was pretty small (from $80 to $180 bytes). But upcoming changes will increase the INIT segment in certain scenarios up to ~ $1000 bytes. So programs with very limited heap+stack might just not been able to move the INIT segment to its run location. But moving the INIT segment to the later BSS allows it to occupy the later BSS+heap+stack. In order to allow that the constructors are _NOT_ allowed anymore to access the BSS. Rather they must use the DATA segment or the new INITBSS segment. The latter isn't cleared at any point so the constructors may use it to expose values to the main program. However they must make sure to always write the values as they are not pre-initialized.
2015-10-14 20:52:09 +00:00
MAIN: file = %O, define = yes, start = __HEADER_LAST__, size = __OVERLAYSTART__ - __STACKSIZE__ - __HEADER_LAST__;
MOVE: file = %O, start = __INITBSS_LOAD__, size = __HIMEM__ - __BSS_RUN__;
INIT: file = "", start = __BSS_RUN__, size = __HIMEM__ - __BSS_RUN__;
Reduced c64-overlay.cfg's size by factoring out a different common expression.
2015-10-08 10:11:37 +00:00
OVL1ADDR: file = "%O.1", start = __OVERLAYSTART__ - 2, size = $0002;
OVL1: file = "%O.1", start = __OVERLAYSTART__, size = __OVERLAYSIZE__;
OVL2ADDR: file = "%O.2", start = __OVERLAYSTART__ - 2, size = $0002;
OVL2: file = "%O.2", start = __OVERLAYSTART__, size = __OVERLAYSIZE__;
OVL3ADDR: file = "%O.3", start = __OVERLAYSTART__ - 2, size = $0002;
OVL3: file = "%O.3", start = __OVERLAYSTART__, size = __OVERLAYSIZE__;
OVL4ADDR: file = "%O.4", start = __OVERLAYSTART__ - 2, size = $0002;
OVL4: file = "%O.4", start = __OVERLAYSTART__, size = __OVERLAYSIZE__;
OVL5ADDR: file = "%O.5", start = __OVERLAYSTART__ - 2, size = $0002;
OVL5: file = "%O.5", start = __OVERLAYSTART__, size = __OVERLAYSIZE__;
OVL6ADDR: file = "%O.6", start = __OVERLAYSTART__ - 2, size = $0002;
OVL6: file = "%O.6", start = __OVERLAYSTART__, size = __OVERLAYSIZE__;
OVL7ADDR: file = "%O.7", start = __OVERLAYSTART__ - 2, size = $0002;
OVL7: file = "%O.7", start = __OVERLAYSTART__, size = __OVERLAYSIZE__;
OVL8ADDR: file = "%O.8", start = __OVERLAYSTART__ - 2, size = $0002;
OVL8: file = "%O.8", start = __OVERLAYSTART__, size = __OVERLAYSIZE__;
OVL9ADDR: file = "%O.9", start = __OVERLAYSTART__ - 2, size = $0002;
OVL9: file = "%O.9", start = __OVERLAYSTART__, size = __OVERLAYSIZE__;
Added secondary linker config for C64 overlays (incl. demo program). git-svn-id: svn://svn.cc65.org/cc65/trunk@5679 b7a2c559-68d2-44c3-8de9-860c34a00d81
2012-06-03 16:16:11 +00:00
}
SEGMENTS {
Changed run location of INIT segment. So far the INIT segment was run from the later heap+stack. Now the INIT segment is run from the later BSS. The background is that so far the INIT segment was pretty small (from $80 to $180 bytes). But upcoming changes will increase the INIT segment in certain scenarios up to ~ $1000 bytes. So programs with very limited heap+stack might just not been able to move the INIT segment to its run location. But moving the INIT segment to the later BSS allows it to occupy the later BSS+heap+stack. In order to allow that the constructors are _NOT_ allowed anymore to access the BSS. Rather they must use the DATA segment or the new INITBSS segment. The latter isn't cleared at any point so the constructors may use it to expose values to the main program. However they must make sure to always write the values as they are not pre-initialized.
2015-10-14 20:52:09 +00:00
ZEROPAGE: load = ZP, type = zp;
LOADADDR: load = LOADADDR, type = ro;
EXEHDR: load = HEADER, type = ro;
STARTUP: load = MAIN, type = ro;
LOWCODE: load = MAIN, type = ro, optional = yes;
CODE: load = MAIN, type = ro;
RODATA: load = MAIN, type = ro;
DATA: load = MAIN, type = rw;
INITBSS: load = MAIN, type = bss, define = yes;
BSS: load = MAIN, type = bss, define = yes;
INIT: load = MOVE, run = INIT, type = ro, define = yes;
OVL1ADDR: load = OVL1ADDR, type = ro;
OVERLAY1: load = OVL1, type = ro, define = yes, optional = yes;
OVL2ADDR: load = OVL2ADDR, type = ro;
OVERLAY2: load = OVL2, type = ro, define = yes, optional = yes;
OVL3ADDR: load = OVL3ADDR, type = ro;
OVERLAY3: load = OVL3, type = ro, define = yes, optional = yes;
OVL4ADDR: load = OVL4ADDR, type = ro;
OVERLAY4: load = OVL4, type = ro, define = yes, optional = yes;
OVL5ADDR: load = OVL5ADDR, type = ro;
OVERLAY5: load = OVL5, type = ro, define = yes, optional = yes;
OVL6ADDR: load = OVL6ADDR, type = ro;
OVERLAY6: load = OVL6, type = ro, define = yes, optional = yes;
OVL7ADDR: load = OVL7ADDR, type = ro;
OVERLAY7: load = OVL7, type = ro, define = yes, optional = yes;
OVL8ADDR: load = OVL8ADDR, type = ro;
OVERLAY8: load = OVL8, type = ro, define = yes, optional = yes;
OVL9ADDR: load = OVL9ADDR, type = ro;
OVERLAY9: load = OVL9, type = ro, define = yes, optional = yes;
Added secondary linker config for C64 overlays (incl. demo program). git-svn-id: svn://svn.cc65.org/cc65/trunk@5679 b7a2c559-68d2-44c3-8de9-860c34a00d81
2012-06-03 16:16:11 +00:00
}
FEATURES {
Just some beautification. git-svn-id: svn://svn.cc65.org/cc65/trunk@5984 b7a2c559-68d2-44c3-8de9-860c34a00d81
2013-02-12 20:55:19 +00:00
CONDES: type = constructor,
Added missing __CALLIRQ__ import attribute. git-svn-id: svn://svn.cc65.org/cc65/trunk@5983 b7a2c559-68d2-44c3-8de9-860c34a00d81
2013-02-12 20:22:27 +00:00
label = __CONSTRUCTOR_TABLE__,
Just some beautification. git-svn-id: svn://svn.cc65.org/cc65/trunk@5984 b7a2c559-68d2-44c3-8de9-860c34a00d81
2013-02-12 20:55:19 +00:00
count = __CONSTRUCTOR_COUNT__,
segment = INIT;
CONDES: type = destructor,
Added missing __CALLIRQ__ import attribute. git-svn-id: svn://svn.cc65.org/cc65/trunk@5983 b7a2c559-68d2-44c3-8de9-860c34a00d81
2013-02-12 20:22:27 +00:00
label = __DESTRUCTOR_TABLE__,
Just some beautification. git-svn-id: svn://svn.cc65.org/cc65/trunk@5984 b7a2c559-68d2-44c3-8de9-860c34a00d81
2013-02-12 20:55:19 +00:00
count = __DESTRUCTOR_COUNT__,
segment = RODATA;
CONDES: type = interruptor,
Added missing __CALLIRQ__ import attribute. git-svn-id: svn://svn.cc65.org/cc65/trunk@5983 b7a2c559-68d2-44c3-8de9-860c34a00d81
2013-02-12 20:22:27 +00:00
label = __INTERRUPTOR_TABLE__,
count = __INTERRUPTOR_COUNT__,
Just some beautification. git-svn-id: svn://svn.cc65.org/cc65/trunk@5984 b7a2c559-68d2-44c3-8de9-860c34a00d81
2013-02-12 20:55:19 +00:00
segment = RODATA,
Added missing __CALLIRQ__ import attribute. git-svn-id: svn://svn.cc65.org/cc65/trunk@5983 b7a2c559-68d2-44c3-8de9-860c34a00d81
2013-02-12 20:22:27 +00:00
import = __CALLIRQ__;
Added secondary linker config for C64 overlays (incl. demo program). git-svn-id: svn://svn.cc65.org/cc65/trunk@5679 b7a2c559-68d2-44c3-8de9-860c34a00d81
2012-06-03 16:16:11 +00:00
}
Reference in New Issue Copy Permalink