Skip to content

ch32v: Fix: Add clobbers to bss/data loops #878

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

Open
Grazfather wants to merge 2 commits into
base: main
Choose a base branch
from
Open

ch32v: Fix: Add clobbers to bss/data loops #878

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
8dc751d
ch32v: Fix: Add clobbers to bss/data loops
Grazfather Jan 24, 2026
7f38c1e
Fix more clobbers
Grazfather Jan 25, 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
25 changes: 22 additions & 3 deletions port/wch/ch32v/src/cpus/main.zig
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -282,7 +282,26 @@ pub const startup_logic = struct {
@export(&startup_logic._system_init, .{ .name = "_system_init" });
asm volatile (
\\jal _system_init
);
// We have clobber all caller-saved registers
::: .{
.x1 = true,
.x5 = true,
.x6 = true,
.x7 = true,
.x10 = true,
.x11 = true,
.x12 = true,
.x13 = true,
.x14 = true,
.x15 = true,
.x16 = true,
.x17 = true,
.x28 = true,
.x29 = true,
.x30 = true,
.x31 = true,
.memory = true,
});

// Load the address of the `microzig_main` function into the `mepc` register
// and transfer control to it using the `mret` instruction.
Expand All @@ -309,7 +328,7 @@ pub const startup_logic = struct {
\\ addi a1, a1, 4
\\ blt a1, a2, clear_bss_loop
\\clear_bss_done:
);
::: .{ .x10 = true, .x11 = true, .x12 = true });

// Copy .data from FLASH to RAM.
asm volatile (
Expand All @@ -324,7 +343,7 @@ pub const startup_logic = struct {
\\ addi a1, a1, 4
\\ bne a1, a2, copy_data_loop
\\copy_done:
);
::: .{ .x10 = true, .x11 = true, .x12 = true, .x13 = true });
}

fn _system_init() callconv(.c) void {
Expand Down
Loading