Revert stdio to initializing itself. Not quite a pretty but that ensures that

we don't blow up by using too much stack space, and simplifies the job of
supporting new architectures, since they don't have to mess with calling foo
init functions in crt0 and cleaning up the resulting damage.
 -Erik

1 files changed, 40 insertions, 27 deletions

diff --git a/libc/sysdeps/linux/arm/crt0pic.S b/libc/sysdeps/linux/arm/crt0pic.S
index a668ac31f..04b1cb755 100644
--- a/libc/sysdeps/linux/arm/crt0pic.S
+++ b/libc/sysdeps/linux/arm/crt0pic.S
@@ -1,21 +1,49 @@
+/* When we enter this piece of code, the program stack looks like this:
+        argc            argument counter (integer)
+        argv[0]         program name (pointer)
+        argv[1...N]     program args (pointers)
+        argv[argc-1]    end of args (integer)
+	NULL
+        env[0...N]      environment variables (pointers)
+        NULL
+	
+   When we are done here, we want
+	a1=argc
+	a2=argv[0]
+	a3=argv[argc+1]
+
+ARM register quick reference:
+
+    Name    Number      APCS Role
+
+    a1      0           argument 1 / integer result / scratch register / argc
+    a2      1           argument 2 / scratch register / argv
+    a3      2           argument 3 / scratch register / envp
+    a4      3           argument 4 / scratch register
+    v1      4           register variable
+    v2      5           register variable
+    v3      6           register variable
+    v4      7           register variable
+    v5      8           register variable
+    sb/v6   9           static base / register variable
+    sl/v7   10          stack limit / stack chunk handle / reg. variable
+    fp      11          frame pointer
+    ip      12          scratch register / new-sb in inter-link-unit calls
+    sp      13          lower end of current stack frame
+    lr      14          link address / scratch register
+    pc      15          program counter
+*/
+
 .text
 	.align 2
 	.global __environ
 	.global _start
 	.global exit
 	.global main
-	.global __libc_init
-	.global __init_stdio
-	.global __stdio_close_all
-	.global _void_void_null_func
 
 	.type   _start,%function
 	.type   exit,%function
 	.type   main,%function
-	.type   __libc_init,%function
-	.type   __init_stdio,%function
-	.type   __stdio_close_all,%function
-	.type   _void_void_null_func,%function
 
 
 
@@ -23,21 +51,18 @@
 @ r1 = argv
 @ r2 = envp
 @ sl = data segment
+#define BASEREG	    r9
 
 .text
 _start:
 	@ adjust the data segment base pointer
 	ldr r3,=__data_start
 	sub sl,sl,r3
-	mov r9,sl
+	mov BASEREG,sl
 
 	ldr r3, .L3
-	str r2,[r9,r3]
+	str r2,[BASEREG,r3]
 	
-	/* Tell libc to initialize whatever it needs */
-        bl __libc_init		    
-        bl __init_stdio
-
 	/* pull argc, argv and envp off the stack */
 	ldr r0,[sp, #0]
 	ldr r1,[sp, #4]
@@ -47,21 +72,9 @@ _start:
 /*	ldr r0,=0  */
 	bl      exit
 
-_void_void_null_func:
-	mov     pc, lr
-
-.weak __libc_init
-__libc_init = _void_void_null_func
-
-.weak __init_stdio
-__init_stdio = _void_void_null_func
-
-.weak __stdio_close_all
-__stdio_close_all = _void_void_null_func
-
 .align 2
 .L3:
-	.word environ
+	.word __environ
 
 
 .data