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__INTERNAL_fmt: Assure correct stack arguments are loaded if FD=stderr

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Kwarde
2025-07-26 01:07:42 +02:00
parent 69d7a52c62
commit e8b47fff6d
1 changed files with 2 additions and 2 deletions
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4
src/console.asm
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@@ -125,8 +125,8 @@ __INTERNAL_fmt:
mov %1, [printfArgs + SIZE_QWORD * r14] mov %1, [printfArgs + SIZE_QWORD * r14]
jmp %%continue jmp %%continue
%%fromStack: %%fromStack:
cmp r15, FD_stdout cmp r15, FD_stderr
je %%stackNoShift jle %%stackNoShift ;simple jle (for test r15,2); entry of this wrapper quits early if passed FD is less than 1, so this simple check is safe enough
mov %1, [rbp + (RBP_OFFSET_CALLER*2 + SIZE_QWORD) + ((r14-5) * SIZE_QWORD)] ;non-printf functions calling __INTERNAL_fmt require RDI to be FD, all args shifted and rbp+RBP_OFFSET_CALLER to r9. Also requires function prologue and a CALL to __INTERNAL_fmt (not a JMP like in printf); hence the RBP_OFFSET_CALLER*2 mov %1, [rbp + (RBP_OFFSET_CALLER*2 + SIZE_QWORD) + ((r14-5) * SIZE_QWORD)] ;non-printf functions calling __INTERNAL_fmt require RDI to be FD, all args shifted and rbp+RBP_OFFSET_CALLER to r9. Also requires function prologue and a CALL to __INTERNAL_fmt (not a JMP like in printf); hence the RBP_OFFSET_CALLER*2
jmp %%continue jmp %%continue
%%stackNoShift: %%stackNoShift: