Linux/ARM fixes with help from doublec

Makefile

@@ -1,4 +1,6 @@
 CC = gcc
+AR = ar
+LD = ld
 
 EXECUTABLE = factor
 VERSION = 0.91

vm/Config.linux.arm

@@ -1,2 +1,3 @@
 include vm/Config.linux
 include vm/Config.arm
+PLAF_DLL_OBJS += vm/os-linux-arm.o

vm/Config.unix

@@ -21,5 +21,5 @@ endif
 # LINKER = gcc -shared -o
 # LINK_WITH_ENGINE = '-Wl,-rpath,$$ORIGIN' -lfactor
 
-LINKER = ar rcs
+LINKER = $(AR) rcs
 LINK_WITH_ENGINE = -Wl,--whole-archive -lfactor -Wl,-no-whole-archive

vm/os-linux-arm.c

@@ -0,0 +1,23 @@
+#include "master.h"
+
+void flush_icache(CELL start, CELL len)
+{
+	int result;
+
+	/* XXX: why doesn't this work on Nokia n800? It should behave
+	identically to the below assembly. */
+	/* result = syscall(__ARM_NR_cacheflush,start,start + len,0); */
+
+	__asm__ __volatile__ (
+		"mov     r0, %1\n"
+		"sub     r1, %2, #1\n"
+		"mov     r2, #0\n"
+		"swi     " __sys1(__ARM_NR_cacheflush) "\n"
+		"mov     %0, r0\n"
+		: "=r" (result)
+		: "r" (start), "r" (start + len)
+		: "r0","r1","r2");
+
+	if(result < 0)
+		critical_error("flush_icache() failed",result);
+}

vm/os-linux-arm.h

@@ -8,7 +8,7 @@ INLINE void *ucontext_stack_pointer(void *uap)
 	return (void *)ucontext->uc_mcontext.arm_sp;
 }
 
-INLINE void flush_icache(CELL start, CELL len)
-{
-	syscall(__ARM_NR_cacheflush,start,start + len,0);
-}
+#define UAP_PROGRAM_COUNTER(ucontext) \
+	(((ucontext_t *)(ucontext))->uc_mcontext.arm_pc)
+
+void flush_icache(CELL start, CELL len);