starting to separate platform-specific code to facilitate a PC build

[gbajam22] / src / gba / asmutil.s

diff --git a/src/gba/asmutil.s b/src/gba/asmutil.s
new file mode 100644 (file)
index 0000000..b88a7a1
--- /dev/null
+++ b/src/gba/asmutil.s
@@ -0,0 +1,38 @@
+       .text
+       .thumb
+
+       .globl fillblock_16byte
+fillblock_16byte:
+       push {r4-r6}
+       mov r3, r1
+       mov r4, r1
+       mov r5, r1
+       mov r6, r1
+0:     stmia r0!, {r3, r4, r5, r6}
+       sub r2, #1
+       bne 0b
+       pop {r4-r6}
+       bx lr
+
+       .globl get_pc
+get_pc:
+       mov r0, lr
+       bx lr
+
+       .globl get_sp
+get_sp:
+       mov r0, sp
+       bx lr
+
+       .arm
+       .extern panic_regs
+       .globl get_panic_regs
+       .type get_panic_regs, %function
+get_panic_regs:
+       stmfd sp!, {sp, lr}
+       ldr lr, =panic_regs
+       stm lr, {r0-r15}
+       ldmfd sp!, {r0, lr}
+       ldr r0, =panic_regs + 13 * 4
+       stm r0, {sp, lr}
+       bx lr