Skip to content

Optimize zeroize bss in CRT0 #716

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
ZERICO2005 merged 2 commits into from
Feb 27, 2026
Merged

Optimize zeroize bss in CRT0 #716

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
f78cb40
size optimized bss_zeroize
ZERICO2005 Feb 26, 2026
93e8067
use ti.boot.memclear to zeroize bss
ZERICO2005 Feb 26, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
26 changes: 9 additions & 17 deletions src/crt/crt0.S
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -37,6 +37,7 @@
.equ ti.PopRealO1, 0x0205DC
.equ ti.MovFrOP1, 0x02032C
.equ ti.ClrLCDFull, 0x020808
.equ ti.boot.memclear, 0x0000B0

.section .header,"ax",@progbits

Expand Down Expand Up @@ -173,24 +174,15 @@ ___libload_libs_ret:
call ti.usb_DisableTimer
di

.L.bss_zeroize:
ld hl, ___bss_len
ld bc, 0
xor a, a
sbc hl, bc
jr z, .L.bss_done
ld de, ___bss_low
push de
ld (de), a
dec hl
sbc hl, bc
pop hl
jr z, .L.bss_done
; zeroize bss
ld hl, ___bss_low
ld bc, ___bss_len
dec bc
inc de
ldir
.L.bss_done:
push bc
push hl
; void memclear(void *dst, size_t size)
call ti.boot.memclear
pop hl
pop hl

res 1, (iy + 0x0D) ; no text buffer
res 3, (iy + 0x4A) ; use first shadow buffer
Expand Down
Loading