1 PROC_FRAME sample 2 db 048h; emit a REX prefix, to enable hot-patching 3 push rbp 4 [pushreg rbp] 5 sub rsp, 040h 6 [allocstack 040h] 7 lea rbp, [rsp+020h] 8 [setframe rbp, 020h] 9 movdqa [rbp], xmm7 10 [savexmm128 xmm7, 020h];the offset is from the base of the frame 11 ;not the scaled offset of the frame 12 mov [rbp+018h], rsi 13 [savereg rsi, 018h] 14 mov [rsp+010h], rdi 15 [savereg rdi, 010h]; you can still use RSP as the base of the frame 16 ; or any other register you choose 17 END_PROLOGUE 18 19 ; you can modify the stack pointer outside of the prologue (similar to alloca) 20 ; because we have a frame pointer. 21 ; if we didn't have a frame pointer, this would be illegal 22 ; if we didn't make this modification, 23 ; there would be no need for a frame pointer 24 25 sub rsp, 060h 26 27 ; we can unwind from the following AV because of the frame pointer 28 29 mov rax, 0 30 mov rax, [rax] ; AV! 31 32 ; restore the registers that weren't saved with a push 33 ; this isn't part of the official epilog, as described in section 2.5 34 35 movdqa xmm7, [rbp] 36 mov rsi, [rbp+018h] 37 mov rdi, [rbp-010h] 38 39 ; Here's the official epilog 40 41 lea rsp, [rbp-020h] 42 pop rbp 43 ret 44 ENDPROC_FRAME 45 struc kFrame 46 .Fill resq 1 ; fill to 8 mod 16 47 .SavedRdi resq 1 ; saved register RDI 48 .SavedRsi resq 1 ; saved register RSI 49 endstruc 50 51 struc sampleFrame 52 .Fill resq 1 ; fill to 8 mod 16 53 .SavedRdi resq 1 ; Saved Register RDI 54 .SavedRsi resq 1 ; Saved Register RSI 55 endstruc 56 57 PROC_FRAME sample2 58 alloc_stack sampleFrame_size 59 save_reg rdi, sampleFrame.SavedRdi 60 save_reg rsi, sampleFrame.SavedRsi 61 END_PROLOGUE 62 63 ; function body 64 65 mov rsi, [rsp+sampleFrame.SavedRsi] 66 mov rdi, [rsp+sampleFrame.SavedRdi] 67 68 ; Here's the official epilog 69 70 add rsp, sampleFrame_size 71 ret 72 ENDPROC_FRAME 73 74
