-.include "out/ccode.16.s"
-
-
-/****************************************************************
- * Entry macros
- ****************************************************************/
-
- // Call a C function - this does the minimal work necessary to
- // call into C. It sets up %ds, backs up %es, and backs up
- // those registers that are call clobbered by the C compiler.
- .macro ENTRY cfunc
- cld
- pushl %eax // Save registers clobbered by C code
- pushl %ecx
- pushl %edx
- pushw %es
- pushw %ds
- movw %ss, %ax // Move %ss to %ds
- movw %ax, %ds
- pushl %esp // Backup %esp, then clear high bits
- movzwl %sp, %esp
- calll \cfunc
- popl %esp // Restore %esp (including high bits)
- popw %ds // Restore registers saved above
- popw %es
- popl %edx
- popl %ecx
- popl %eax
- .endm
-
- // Call a C function with current register list as an
- // argument. This backs up the registers and sets %eax
- // to point to the backup. On return, the registers are
- // restored from the structure.
- .macro ENTRY_ARG cfunc
- cld
- pushl %eax // Save registers (matches struct bregs)
- pushl %ecx
- pushl %edx
- pushl %ebx
- pushl %esi
- pushl %edi
- pushw %es
- pushw %ds
- movw %ss, %ax // Move %ss to %ds
- movw %ax, %ds
- movl %esp, %ebx // Backup %esp, then zero high bits
- movzwl %sp, %esp
- movl %esp, %eax // First arg is pointer to struct bregs
- calll \cfunc
- movl %ebx, %esp // Restore %esp (including high bits)
- popw %ds // Restore registers (from struct bregs)
- popw %es
- popl %edi
- popl %esi
- popl %ebx
- popl %edx
- popl %ecx
- popl %eax
- .endm
-
- // As above, but don't mangle %esp
- .macro ENTRY_ARG_ESP cfunc
- cld
- pushl %eax // Save registers (matches struct bregs)
- pushl %ecx
- pushl %edx
- pushl %ebx
- pushl %esi
- pushl %edi
- pushw %es
- pushw %ds
- movw %ss, %ax // Move %ss to %ds
- movw %ax, %ds
- movl %esp, %eax // First arg is pointer to struct bregs
- calll \cfunc
- popw %ds // Restore registers (from struct bregs)
- popw %es
- popl %edi
- popl %esi
- popl %ebx
- popl %edx
- popl %ecx
- popl %eax
- .endm
-
- // Macro to reset the 16bit stack
- // Clobbers %ax
- .macro RESET_STACK
- xorw %ax, %ax
- movw %ax, %ss
- movl $ BUILD_STACK_ADDR , %esp
- cld
- .endm
-
- // Specify a location in the fixed part of bios area.
- .macro ORG addr
- .section .text.fixed.addr
- .org \addr - BUILD_START_FIXED
- .endm