microshmup: initial commitmicroshmup

1 files changed, 89 insertions, 0 deletions

diff --git a/microshmup/microshmup.S b/microshmup/microshmup.S
new file mode 100644
index 0000000..fbeb37a
--- /dev/null
+++ b/microshmup/microshmup.S
@@ -0,0 +1,89 @@
+// ================================================================================================
+// Read-only data
+// ================================================================================================
+#ifdef __APPLE__
+    .section __TEXT,__const
+#else
+    .section .rodata
+#endif
+
+s_microshmup: .asciz "microshmup"
+s_microshmup_error: .asciz "microshmup - error"
+
+// ================================================================================================
+// Mutable data
+// ================================================================================================
+#ifdef __APPLE__
+    .section __DATA,__bss
+#else
+    .section .bss
+#endif
+    .p2align 3
+
+g_rnd: .zero 8  // SDL_Renderer *
+g_wnd: .zero 8  // SDL_Window *
+
+// ================================================================================================
+// Code
+// ================================================================================================
+
+#ifdef __APPLE__
+    .section __TEXT,__text
+#else
+    .section .text
+#endif
+
+#ifdef __APPLE__
+#   define SYM(name) _##name
+#else
+#   define SYM(name) name
+#endif
+
+.macro LOADADDR reg, sym
+#ifdef __APPLE__
+    adrp        \reg, \sym\()@PAGE
+    add         \reg, \reg, \sym\()@PAGEOFF
+#else
+    adrp        \reg, \sym
+    add         \reg, \reg, :lo12:\sym
+#endif
+.endm
+
+.global SYM(main)
+
+SYM(main):
+    stp         x29, x30, [sp, #-16]!
+    mov         x29, sp
+
+    mov         w0, #0x30       // SDL_INIT_VIDEO | SDL_INIT_AUDIO
+    bl          SYM(SDL_Init)
+    tst         w0, #0xFF
+    b.eq        sdl_fail
+
+    LOADADDR    x0, s_microshmup
+    mov         w1, #800
+    mov         w2, #600
+    mov         x3, #0
+    LOADADDR    x4, g_wnd
+    LOADADDR    x5, g_rnd
+    bl          SYM(SDL_CreateWindowAndRenderer)
+    tst         w0, #0xFF
+    b.eq        sdl_fail
+
+    mov         w0, #0
+    ldp         x29, x30, [sp], #16
+    ret
+sdl_fail:
+    bl          SYM(SDL_GetError)
+
+    mov         x2, x0
+    mov         w0, #0x10
+    LOADADDR    x1, s_microshmup_error
+    LOADADDR    x9, g_wnd
+    ldr         x3, [x9]
+    bl          SYM(SDL_ShowSimpleMessageBox)
+
+    mov         w0, #1
+    ldp         x29, x30, [sp], #16
+    ret
+