From 7f69b3e394b026d359912adf5670faf255934f5c Mon Sep 17 00:00:00 2001
From: Aleksey Demakov <ademakov@gmail.com>
Date: Sat, 7 Feb 2009 16:15:58 +0000
Subject: [PATCH] integrate mikyt's arm apply patch

---
 jit/jit-apply-arm.c | 43 +++++++++++++++++++++++++++++++++++++++++++
 jit/jit-apply-arm.h | 35 +++++++++++++++++++++++++++++++++++
 2 files changed, 78 insertions(+)

diff --git a/jit/jit-apply-arm.c b/jit/jit-apply-arm.c
index 35d3307..0f0513d 100644
--- a/jit/jit-apply-arm.c
+++ b/jit/jit-apply-arm.c
@@ -97,4 +97,47 @@ void *_jit_create_redirector(unsigned char *buf, void *func,
 	return (void *)buf;
 }
 
+/**
+ * Creates the indirector, that is the trampoline that permits the Just In Time 
+ * compilation of a method the first time that it is executed and its direct execution
+ * the following times
+ */
+void *_jit_create_indirector(unsigned char *buf, void **entry)
+{
+	arm_inst_buf inst;
+	void *start = (void *)buf;
+
+	/* Initialize the instruction buffer */
+	arm_inst_buf_init(inst, buf, buf + jit_indirector_size);
+
+	//Load the content of memory at address "entry", that is, the entry point of the function
+	arm_mov_reg_imm(inst,ARM_WORK,entry);
+	arm_mov_reg_membase(inst,ARM_WORK,ARM_WORK,0,4);
+	
+	/* Jump to the entry point. */
+	arm_mov_reg_reg(inst, ARM_PC, ARM_WORK);
+
+	/* Flush the cache lines that we just wrote */
+	jit_flush_exec(buf, ((unsigned char *)(inst.current)) - buf);
+	
+	return start;
+}
+
+void _jit_pad_buffer(unsigned char *buf, int len)
+{
+	arm_inst_buf inst;
+	
+	/* Initialize the instruction buffer */
+	arm_inst_buf_init(inst, buf, buf + len*4);
+	while(len > 0)
+	{
+		/* Traditional arm NOP */
+		arm_nop(inst);
+		--len;
+	}
+	
+	/* Flush the cache lines that we just wrote */
+	jit_flush_exec(buf, ((unsigned char *)(inst.current)) - buf);
+}
+
 #endif /* arm */
diff --git a/jit/jit-apply-arm.h b/jit/jit-apply-arm.h
index a9dc963..2ccaa98 100644
--- a/jit/jit-apply-arm.h
+++ b/jit/jit-apply-arm.h
@@ -36,4 +36,39 @@
  */
 #define	jit_redirector_size		128
 
+/*
+ * The number of bytes that are needed for a indirector stub.
+ * This includes any extra bytes that are needed for alignment.
+ */
+#define	jit_indirector_size		24
+
+/*
+ * We should pad unused code space with NOP's.
+ */
+#define	jit_should_pad			1
+
+/*
+ * Defines the alignment for the stack pointer at a public interface.
+ * As of the "Procedure Call Standard for the ARM Architecture" (AAPCS release 2.07)
+ *    SP mod 8 = 0
+ * must always be true at every public interface (function calls, etc)
+ */
+#define JIT_SP_ALIGN_PUBLIC 8
+
+/*
+ * Redefine jit_builtin_apply in order to correctly align the stack pointer
+ * to JIT_SP_ALING_PUBLIC bytes before calling __builtin_apply to execute the
+ * jit-compiled function
+ */
+#define	jit_builtin_apply(func,args,size,return_float,return_buf)	\
+do {									\
+	register void *sp asm("sp");					\
+	while(((unsigned int)sp) % JIT_SP_ALIGN_PUBLIC != 0)		\
+	{								\
+		sp=(void *)(((unsigned int) sp)+1);			\
+	}								\
+	(return_buf) = __builtin_apply					\
+	((void (*)())(func), (args), (size));				\
+} while (0)
+
 #endif	/* _JIT_APPLY_ARM_H */
-- 
2.47.3