| PROC_FRAME sample |
| db 048h; emit a REX prefix, to enable hot-patching |
| push rbp |
| [pushreg rbp] |
| sub rsp, 040h |
| [allocstack 040h] |
| lea rbp, [rsp+020h] |
| [setframe rbp, 020h] |
| movdqa [rbp], xmm7 |
| [savexmm128 xmm7, 020h];the offset is from the base of the frame |
| ;not the scaled offset of the frame |
| mov [rbp+018h], rsi |
| [savereg rsi, 018h] |
| mov [rsp+010h], rdi |
| [savereg rdi, 010h]; you can still use RSP as the base of the frame |
| ; or any other register you choose |
| END_PROLOGUE |
| |
| ; you can modify the stack pointer outside of the prologue (similar to alloca) |
| ; because we have a frame pointer. |
| ; if we didn't have a frame pointer, this would be illegal |
| ; if we didn't make this modification, |
| ; there would be no need for a frame pointer |
| |
| sub rsp, 060h |
| |
| ; we can unwind from the following AV because of the frame pointer |
| |
| mov rax, 0 |
| mov rax, [rax] ; AV! |
| |
| ; restore the registers that weren't saved with a push |
| ; this isn't part of the official epilog, as described in section 2.5 |
| |
| movdqa xmm7, [rbp] |
| mov rsi, [rbp+018h] |
| mov rdi, [rbp-010h] |
| |
| ; Here's the official epilog |
| |
| lea rsp, [rbp-020h] |
| pop rbp |
| ret |
| ENDPROC_FRAME |
| struc kFrame |
| .Fill resq 1 ; fill to 8 mod 16 |
| .SavedRdi resq 1 ; saved register RDI |
| .SavedRsi resq 1 ; saved register RSI |
| endstruc |
| |
| struc sampleFrame |
| .Fill resq 1 ; fill to 8 mod 16 |
| .SavedRdi resq 1 ; Saved Register RDI |
| .SavedRsi resq 1 ; Saved Register RSI |
| endstruc |
| |
| PROC_FRAME sample2 |
| alloc_stack sampleFrame_size |
| save_reg rdi, sampleFrame.SavedRdi |
| save_reg rsi, sampleFrame.SavedRsi |
| END_PROLOGUE |
| |
| ; function body |
| |
| mov rsi, [rsp+sampleFrame.SavedRsi] |
| mov rdi, [rsp+sampleFrame.SavedRdi] |
| |
| ; Here's the official epilog |
| |
| add rsp, sampleFrame_size |
| ret |
| ENDPROC_FRAME |
| |
