| author |  Alex Rønne Petersen <alex@alexrp.com> 2024-09-11 07:32:44+02:00 |
| committer |  Andrew Kelley <andrew@ziglang.org> 2024-09-12 20:10:45-07:00 |
| log | b56a667ecdb9f34dbd60d247d4237bc008755979 |
| tree | 52f200c6650f96d4d6d699ef64f642cc1621a05e |
| parent | cf691543323be9bb663aac2d19f62412435a4d39 |
start: Rewrite arm code to work for thumb1 too.
0ecc6332b4eb1ced547ffa38f57471134aaa4d13 improved things for thumb2, but thumb1
has a much smaller permissible instruction set. This commit makes that work.1 files changed, 7 insertions(+), 5 deletions(-)
lib- std
lib/std/start.zig+7-5
| ... | ... | @@ -280,12 +280,14 @@ fn _start() callconv(.Naked) noreturn { |
| 280 | 280 | \\ b %[posixCallMainAndExit] |
| 281 | 281 | , |
| 282 | 282 | .arm, .armeb, .thumb, .thumbeb => |
| 283 | \\ mov fp, #0 | |
| 284 | \\ mov lr, #0 | |
| 283 | // Note that this code must work for Thumb-1. | |
| 284 | \\ movs v1, #0 | |
| 285 | \\ mov fp, v1 | |
| 286 | \\ mov lr, v1 | |
| 285 | 287 | \\ mov a1, sp |
| 286 | \\ mov ip, sp | |
| 287 | \\ and ip, ip, #-16 | |
| 288 | \\ mov sp, ip | |
| 288 | \\ subs v1, #16 | |
| 289 | \\ ands v1, a1 | |
| 290 | \\ mov sp, v1 | |
| 289 | 291 | \\ b %[posixCallMainAndExit] |
| 290 | 292 | , |
| 291 | 293 | .csky => |