mescc: Mes C Library: ARM: _start: Inline fake asm.

* lib/linux/arm-mes-gcc/crt1.c (_start): Use inline fake asm.

lib/linux/arm-mes-gcc/crt1.c

@@ -22,11 +22,11 @@
 #include <mes/lib-mini.h>
 //int main (int argc, char *argv[], char *envp[]);
 
-#if !__TINYC__
 /* Note: GCC automatically emits a preable in order to set up the
 frame pointer: "push {fp}" "add fp, sp, 0"
  */
 // *INDENT-OFF*
+#if !__TINYC__
 void
 _start ()
 {
@@ -76,46 +76,81 @@ _start ()
        );
 }
 #else //__TINYC__
-__asm__ (".global _start\n");
-__asm__ ("_start:\n");
-__asm__ (".int 0xe52db004\n"); //push  {fp}      ; (str fp, [sp, #-4]!)
-__asm__ (".int 0xe28db000\n"); //add   fp, sp, #0
-__asm__ (".int 0xe3a00000\n"); //mov   r0, #0
-__asm__ (".int 0xe1a02000\n"); //mov   r2, r0
-__asm__ (".int 0xe3003000\n"); //movw  r3, #0
-__asm__ (".int 0xe3403000\n"); //movt  r3, #0
-__asm__ (".int 0xe5832000\n"); //str   r2, [r3]
-__asm__ (".int 0xe3a00001\n"); //mov   r0, #1
-__asm__ (".int 0xe1a02000\n"); //mov   r2, r0
-__asm__ (".int 0xe3003000\n"); //movw  r3, #0
-__asm__ (".int 0xe3403000\n"); //movt  r3, #0
-__asm__ (".int 0xe5832000\n"); //str   r2, [r3]
-__asm__ (".int 0xe3a00002\n"); //mov   r0, #2
-__asm__ (".int 0xe1a02000\n"); //mov   r2, r0
-__asm__ (".int 0xe3003000\n"); //movw  r3, #0
-__asm__ (".int 0xe3403000\n"); //movt  r3, #0
-__asm__ (".int 0xe5832000\n"); //str   r2, [r3]
-__asm__ (".int 0xe59b0004\n"); //ldr   r0, [fp, #4]
-__asm__ (".int 0xe28b1008\n"); //add   r1, fp, #8
+void
+_start ()
+{
+#if 0
+  __asm__ (".int 0xe320f000\n"); //nop   {0}
+  __asm__ (".int 0xe320f000\n"); //nop   {0}
+#endif
+
+  int *in = &__stdin;
+  int *out = &__stdout;
+  int *err = &__stderr;
+  char ***env = &environ;
+
+#if 0
+  __asm__ (".int 0xe320f000\n"); //nop   {0}
+  __asm__ (".int 0xe320f000\n"); //nop   {0}
+
+  __asm__ (".int 0xe320f000\n"); //nop   {0}
+  *in = 0x22;
+  __asm__ (".int 0xe320f000\n"); //nop   {0}
+  *out = 0x33;
+  __asm__ (".int 0xe320f000\n"); //nop   {0}
+  *err = 0x44;
+  __asm__ (".int 0xe320f000\n"); //nop   {0}
+  *env = 0x55;
+  __asm__ (".int 0xe320f000\n"); //nop   {0}
+#endif
+
+  /* environ = argv + argc + 1 */
+  __asm__ (".int 0xe59b000c\n"); //ldr   r0, [fp, #12]
+  __asm__ (".int 0xe28b1010\n"); //add   r1, fp, #16
+
   __asm__ (".int 0xe2802001\n"); //add   r2, r0, #1
   __asm__ (".int 0xe1a02102\n"); //lsl   r2, r2, #2
   __asm__ (".int 0xe0822001\n"); //add   r2, r2, r1
+
+  // setup argc, argv, envp parameters on stack
   __asm__ (".int 0xe52d2004\n"); //push  {r2}      ; (str r2, [sp, #-4]!)
   __asm__ (".int 0xe52d1004\n"); //push  {r1}      ; (str r1, [sp, #-4]!)
   __asm__ (".int 0xe52d0004\n"); //push  {r0}      ; (str r0, [sp, #-4]!)
   __asm__ (".int 0xe1a02002\n"); //mov   r2, r2
-__asm__ (".int 0xe3003000\n"); //movw  r3, #0
-__asm__ (".int 0xe3403000\n"); //movt  r3, #0
-__asm__ (".int 0xe5832000\n"); //str   r2, [r3]
+
+  // *in = 0;
+  __asm__ (".int 0xe3a01000\n"); //mov   r1, #0
+  __asm__ (".int 0xe51b0004\n"); //ldr   r0, [fp, #-4]
+  __asm__ (".int 0xe5801000\n"); //str   r1, [r0]
+  __asm__ (".int 0xe320f000\n"); //nop   {0}
+
+  // *out = 1;
+  __asm__ (".int 0xe3a01001\n"); //mov   r1, #1
+  __asm__ (".int 0xe51b0008\n"); //ldr   r0, [fp, #-8]
+  __asm__ (".int 0xe5801000\n"); //str   r1, [r0]
+  __asm__ (".int 0xe320f000\n"); //nop   {0}
+
+  // *err = 2;
+  __asm__ (".int 0xe3a01002\n"); //mov   r1, #2
+  __asm__ (".int 0xe51b000c\n"); //ldr   r0, [fp, #-12]
+  __asm__ (".int 0xe5801000\n"); //str   r1, [r0]
+  __asm__ (".int 0xe320f000\n"); //nop   {0}
+
+  // *env = [sp, #8]
+  __asm__ (".int 0xe59d1008\n"); //ldr   r1, [sp, #8]
+  __asm__ (".int 0xe51b0010\n"); //ldr   r0, [fp, #-16]
+  __asm__ (".int 0xe5801000\n"); //str   r1, [r0]
+  __asm__ (".int 0xe320f000\n"); //nop   {0}
+
+  // setup argc, argv, envp parameters in registers
   __asm__ (".int 0xe59d0000\n"); //ldr   r0, [sp]
   __asm__ (".int 0xe59d1004\n"); //ldr   r1, [sp, #4]
   __asm__ (".int 0xe59d2008\n"); //ldr   r2, [sp, #8]
-__asm__ (".int 0xebfffffe\n"); //bl    0 <main>
+  main ();
+
   __asm__ (".int 0xe3a07001\n"); //mov   r7, #1
   __asm__ (".int 0xef000000\n"); //svc   0x00000000
   __asm__ (".int 0xe320f003\n"); //wfi
   __asm__ (".int 0xe320f000\n"); //nop   {0}
-__asm__ (".int 0xe28bd000\n"); //add   sp, fp, #0
-__asm__ (".int 0xe49db004\n"); //pop   {fp}      ; (ldr fp, [sp], #4)
-__asm__ (".int 0xe12fff1e\n"); //bx    lr
+}
 #endif //__TINYC__