Author: leo
Date: Wed Feb 8 12:23:23 2006
New Revision: 11476
Modified:
trunk/src/jit/i386/jit_emit.h
Log:
JIT/x86 - try aligning the function address (turned off)
Modified: trunk/src/jit/i386/jit_emit.h
==============================================================================
--- trunk/src/jit/i386/jit_emit.h (original)
+++ trunk/src/jit/i386/jit_emit.h Wed Feb 8 12:23:23 2006
@@ -2910,6 +2910,32 @@ jit_set_args_pc(Parrot_jit_info_t *jit_i
}
}
+/*
+ * if jit_emit_noop is defined, it does align a jump target
+ * to 1 << JUMP_ALIGN
+ * It may emit exactly one byte, or some desired padding.
+ * The instructions must perform like a noop.
+ *
+ * Alignment effects seem to be rather processor specific and
+ * it's not quite clear if the branch src or target should be
+ * aligned. Turned off for now.
+ *
+ * s. also info gcc /align-jump
+ *
+ * noop; mov %esi, %esi; lea 0(%esi), %esi
+ */
+
+# define jit_emit_noop(pc) do { \
+ switch ( ((unsigned long) pc) & 3) { \
+ case 1: *pc++ = (char) 0x8d; *pc++ = (char) 0x76; *pc++ = (char) 0x00;
break; \
+ case 2: *pc++ = (char) 0x89; *pc++ = (char) 0xf6; break; \
+ case 3: *pc++ = (char) 0x90; break; \
+ } \
+ } while (0)
+
+# define JUMP_ALIGN 0
+# define SUB_ALIGN 0
+
#if JIT_EMIT == 0
static void
@@ -3133,6 +3159,12 @@ Parrot_jit_begin_sub_regs(Parrot_jit_inf
jit_restore_regs(jit_info, interpreter, -1);
jit_emit_stack_frame_leave(NATIVECODE);
emitm_ret(NATIVECODE);
+ /* align the inner sub */
+# if SUB_ALIGN
+ while ((long)jit_info->native_ptr & ((1<<SUB_ALIGN) - 1)) {
+ jit_emit_noop(jit_info->native_ptr);
+ }
+# endif
/* fixup call statement */
L1[1] = NATIVECODE - L1 - 5;
}
@@ -3748,27 +3780,6 @@ Parrot_jit_init(Interp *interpreter)
return &arch_info;
}
-/*
- * if jit_emit_noop is defined, it does align a jump target
- * to 1 << JUMP_ALIGN
- * It may emit exactly one byte, or some desired padding.
- * The instructions must perfomr like a noop.
- *
- *
- * s. also info gcc /align-jump
- *
- * noop; mov %esi, %esi; lea 0(%esi), %esi
- */
-
-# define jit_emit_noop(pc) do { \
- switch ( ((unsigned long) pc) & 3) { \
- case 1: *pc++ = (char) 0x8d; *pc++ = (char) 0x76; *pc++ = (char) 0x00;
break; \
- case 2: *pc++ = (char) 0x89; *pc++ = (char) 0xf6; break; \
- case 3: *pc++ = (char) 0x90; break; \
- } \
- } while (0)
-
-# define JUMP_ALIGN 2
/* registers are either allocate per section or per basic block
* set this to 1 or 0 to change allocation scheme
