Make considerably more progress on AARCH64

- Utilities like pledge.com now build
- kprintf() will no longer balk at 48-bit addresses
- There's a new aarch64-dbg build mode that should work
- gc() and defer() are mostly pacified; avoid using them on aarch64
- THIRD_PART_STB now has Arm Neon intrinsics for fast image handling

examples/auto-launch-gdb-on-crash.c

@@ -41,6 +41,6 @@
 
 int main(int argc, char *argv[]) {
   ShowCrashReports();
-  asm("int3"); /* cf. __die(), perror("msg"), abort(), exit(1), _Exit(1) */
+  __builtin_trap();
   return 0;
 }

examples/breakpoint.c

@@ -23,13 +23,7 @@ int main(int argc, char *argv[]) {
     kprintf("try running: o//tool/build/strace.com %s%n", argv[0]);
   }
 
-  asm volatile("mov\t%4,%%r10\n\t"
-               "mov\t%5,%%r8\n\t"
-               "mov\t%6,%%r9\n\t"
-               "int3"
-               : /* no outputs */
-               : "a"(0), "D"(1), "S"(2), "d"(3), "g"(4), "g"(5), "g"(6)
-               : "r8", "r9", "r10");
+  __builtin_trap();
 
   printf("recovered from SIGTRAP without handler\r\n");
   return 0;

examples/package/lib/build.mk

@@ -96,6 +96,10 @@ $(EXAMPLES_PACKAGE_LIB_A).pkg:					\
 # Invalidates objects in package when makefile is edited.
 $(EXAMPLES_PACKAGE_LIB_A_OBJS): examples/package/lib/build.mk
 
+# let these assembly objects build on aarch64
+o/$(MODE)/examples/package/lib/myasm.o: examples/package/lib/myasm.S
+	@$(COMPILE) -AOBJECTIFY.S $(OBJECTIFY.S) $(OUTPUT_OPTION) -c $<
+
 EXAMPLES_PACKAGE_LIB_LIBS = $(foreach x,$(EXAMPLES_PACKAGE_LIB_ARTIFACTS),$($(x)))
 EXAMPLES_PACKAGE_LIB_SRCS = $(foreach x,$(EXAMPLES_PACKAGE_LIB_ARTIFACTS),$($(x)_SRCS))
 EXAMPLES_PACKAGE_LIB_HDRS = $(foreach x,$(EXAMPLES_PACKAGE_LIB_ARTIFACTS),$($(x)_HDRS))

examples/package/lib/myasm.S

@@ -8,9 +8,18 @@
 //		somehow they usually make code faster
 //		it's convention for keeping stack 16-byte aligned
 //		cpus still devote much to pushing & popping b/c i386
-MyAsm:	push	%rbp
+MyAsm:
+
+#ifdef __x86_64__
+	push	%rbp
 	mov	%rsp,%rbp
 	call	MyPrint2
 	pop	%rbp
+#elif defined(__aarch64__)
+	bl	MyPrint2
+#else
+#error "unsupported architecture"
+#endif
+
 	ret
 	.endfn	MyAsm,globl

examples/ucontext-sigfpe-recovery.c

@@ -16,6 +16,8 @@
 #include "libc/sysv/consts/sig.h"
 #include "third_party/xed/x86.h"
 
+#ifdef __x86_64__
+
 /**
  * @fileoverview How to change CPU state on signal delivery
  *
@@ -43,3 +45,5 @@ int main(int argc, char *argv[]) {
   printf("123/0 = %ld\n", 123 / x);
   return 0;
 }
+
+#endif /* __x86_64__ */

examples/vga.c

@@ -15,6 +15,8 @@
 #include "libc/str/str.h"
 #include "libc/sysv/consts/termios.h"
 
+#ifdef __x86_64__
+
 /**
  * @fileoverview Bare Metal VGA TTY demo.
  *
@@ -58,3 +60,5 @@ int main(int argc, char *argv[]) {
     }
   }
 }
+
+#endif /* __x86_64__ */

examples/vga2.c

@@ -15,6 +15,8 @@
 #include "libc/str/str.h"
 #include "libc/sysv/consts/termios.h"
 
+#ifdef __x86_64__
+
 /**
  * @fileoverview Demo of program crash reporting with Bare Metal VGA TTY.
  *
@@ -35,5 +37,8 @@ int main(int argc, char *argv[]) {
     printf("argv[%d] = \"%s\"\n", i, argv[i]);
   }
   printf("\e[92;44mHello World!\e[0m %d\n", 1 / (x + y - 3));
-  for (;;);
+  for (;;)
+    ;
 }
+
+#endif /* __x86_64__ */

examples/wall.c

@@ -132,12 +132,12 @@ int main(int argc, char *argv[]) {
   appends(&msg, "\r\n\e[K\e[0m\e8");  // restore
 
   // try to send message to all pseudoteletypewriters
-  for (int i = 0;; ++i) {
+  for (int i = 0; i < 100; ++i) {
     int fd;
     char pts[32];
     snprintf(pts, sizeof(pts), "/dev/pts/%d", i);
     if ((fd = open(pts, O_WRONLY | O_NOCTTY)) == -1) {
-      if (errno == ENOENT) break;
+      if (errno == ENOENT) continue;
       if (g_verbose) perror(pts);
     }
     write(fd, msg, appendz(msg).i);