| GC on EWS4800 |
| ------------- |
| |
| 1. About EWS4800 |
| EWS4800 is 32bit/64bit workstation. |
| |
| Vender: NEC Corporation |
| OS: UX/4800 R9.* - R13.* (SystemV R4.2) |
| CPU: R4000, R4400, R10000 (MIPS) |
| |
| 2. Compiler |
| |
| 32bit: |
| Use ANSI C compiler. |
| CC = /usr/abiccs/bin/cc |
| |
| 64bit: |
| Use 64bit ANSI C compiler. |
| CC = /usr/ccs64/bin/cc |
| AR = /usr/ccs64/bin/ar |
| |
| 3. ELF file format |
| *** Caution: The following infomation is empirical. *** |
| |
| 32bit: |
| ELF file has an unique format. (See a.out(4) and end(3C).) |
| |
| &_start |
| : text segment |
| &etext |
| DATASTART |
| : data segment (initialized) |
| &edata |
| DATASTART2 |
| : data segment (uninitialized) |
| &end |
| |
| Here, DATASTART and DATASTART2 are macros of GC, and are defined as |
| the following equations. (See include/private/gcconfig.h.) |
| The algorithm for DATASTART is similar with the function |
| GC_SysVGetDataStart() in os_dep.c. |
| |
| DATASTART = ((&etext + 0x3ffff) & ~0x3ffff) + (&etext & 0xffff) |
| |
| Dynamically linked: |
| DATASTART2 = (&_gp + 0x8000 + 0x3ffff) & ~0x3ffff |
| |
| Statically linked: |
| DATASTART2 = &edata |
| |
| GC has to check addresses both between DATASTART and &edata, and |
| between DATASTART2 and &end. If a program accesses between &etext |
| and DATASTART, or between &edata and DATASTART2, the segmentation |
| error occurs and the program stops. |
| |
| If a program is statically linked, there is not a gap between |
| &edata and DATASTART2. The global symbol &_DYNAMIC_LINKING is used |
| for the detection. |
| |
| 64bit: |
| ELF file has a simple format. (See end(3C).) |
| |
| _ftext |
| : text segment |
| _etext |
| _fdata = DATASTART |
| : data segment (initialized) |
| _edata |
| _fbss |
| : data segment (uninitialized) |
| _end = DATAEND |
| |
| -- |
| Hironori SAKAMOTO <hsaka@mth.biglobe.ne.jp> |
| |
| |
| When using the new "configure; make" build process, please |
| run configure with the --disable-shared option. "Make check" does not |
| yet pass with dynamic libraries. Ther reasons for that are not yet |
| understood. (HB, paraphrasing message from Hironori SAKAMOTO.) |
| |
