| .text |
| |
| .global init_thunks |
| .type init_thunks, @function |
| init_thunks: |
| mov $0x2b, %rax /* USER32_DS */ |
| mov %rax,%ss |
| mov %rax,%ds |
| mov %rax,%es |
| ret |
| .size init_thunks, .-init_thunks |
| |
| .global call32_from_64 |
| .type call32_from_64, @function |
| call32_from_64: |
| // rdi: stack to use |
| // esi: function to call |
| |
| // Save registers |
| pushq %rbx |
| pushq %rbp |
| pushq %r12 |
| pushq %r13 |
| pushq %r14 |
| pushq %r15 |
| pushfq |
| |
| // Switch stacks |
| mov %rsp,(%rdi) |
| mov %rdi,%rsp |
| |
| // Switch to compatibility mode |
| pushq $0x23 /* USER32_CS */ |
| pushq $1f |
| lretq |
| |
| 1: |
| .code32 |
| // Call the function |
| call *%esi |
| // Switch back to long mode |
| jmp $0x33,$1f |
| .code64 |
| |
| 1: |
| // Restore the stack |
| mov (%rsp),%rsp |
| |
| // Restore registers |
| popfq |
| popq %r15 |
| popq %r14 |
| popq %r13 |
| popq %r12 |
| popq %rbp |
| popq %rbx |
| |
| ret |
| |
| .size call32_from_64, .-call32_from_64 |
