Re-enable ARM32 JIT compiler

[Andrew Haley]

The bug was actually in the asm interpreter, but it broke the JIT.
Here:

@@ -870,7 +873,7 @@

 	SLOW_ENTRY
 empty_entry:
-	ldrh	r3, [r0, #42]
+	ldrh	r3, [r0, #METHOD_SIZEOFPARAMETERS]

This code adjusts the stack pointer after an empty method is called.
42 is wrong: it should be the field offset of
methodOopDesc::_size_of_parameters.  While I was at it I found a
couple more literals and changed them to symbolic names.

I also took the opportunity to fix a few bugs.  I made the tracing
code more robust, and commented out some debugging calls that slow
down the interpreter.  I also fixed a bug in the helper routines that
were using a static local to hold the address of the card table base:
this is pointlessly slower than using a non-static local.

Andrew.


# HG changeset patch
# User aph
# Date 1395056000 0
# Node ID 2de808a5820a68b390d05ab56934dbca8dbd9dcf
# Parent  720c95f2266397040d878e255015b638d63c8c56
Re-enable ARM32 JIT compiler.

Replace literal offsets for METHOD_SIZEOFPARAMETERS and
ISTATE_NEXT_FRAME with correct symbolic names.
Fix trace code not to dereference null pointers.
Correct Helper_aputfield and helper_aastore not to use static
_byte_map_base.
Comment-out calls to TRACE.
Make sure that ISTATE_METHOD and ISTATE_SELF_LINK are set even when
JITting fails.

diff -r 720c95f22663 -r 2de808a5820a src/cpu/zero/vm/asm_helper.cpp
--- a/src/cpu/zero/vm/asm_helper.cpp	Thu Feb 20 15:02:19 2014 +0000
+++ b/src/cpu/zero/vm/asm_helper.cpp	Mon Mar 17 11:33:20 2014 +0000
@@ -378,22 +378,16 @@
 	  goto handle_exception;
 	}
       }
-      oop* elem_loc = (oop*)(((address) arrayref->base(T_OBJECT)) + index * sizeof(oop));
-      // *(oop*)(((address) arrayref->base(T_OBJECT)) + index * sizeof(oop)) = value;
-      *elem_loc = value;
-      // Mark the card
-      BarrierSet* bs = Universe::heap()->barrier_set();
-      static volatile jbyte* _byte_map_base = (volatile jbyte*)(((CardTableModRefBS*)bs)->byte_map_base);
-      OrderAccess::release_store(&_byte_map_base[(uintptr_t)elem_loc >> CardTableModRefBS::card_shift], 0);
+      ((objArrayOopDesc *) arrayref)->obj_at_put(index, value);
     }
 handle_exception:
     return istate->thread()->pending_exception();
 }

-extern "C" void Helper_aputfield(oop obj)
+extern "C" void Helper_aputfield(oop obj, oop val, int offset)
 {
       BarrierSet* bs = Universe::heap()->barrier_set();
-      static volatile jbyte* _byte_map_base = (volatile jbyte*)(((CardTableModRefBS*)bs)->byte_map_base);
+      jbyte* _byte_map_base = (((CardTableModRefBS*)bs)->byte_map_base);
       OrderAccess::release_store(&_byte_map_base[(uintptr_t)obj >> CardTableModRefBS::card_shift], 0);
 }

diff -r 720c95f22663 -r 2de808a5820a src/cpu/zero/vm/cppInterpreter_arm.S
--- a/src/cpu/zero/vm/cppInterpreter_arm.S	Thu Feb 20 15:02:19 2014 +0000
+++ b/src/cpu/zero/vm/cppInterpreter_arm.S	Mon Mar 17 11:33:20 2014 +0000
@@ -526,10 +526,13 @@
 	mrs	r4, cpsr
 	mov	r0, jpc
 	ldr	r1, [thread, #THREAD_TOP_ZERO_FRAME]
+	cmp	r1, #0
 	sub	r1, r1, #ISTATE_NEXT_FRAME
+	beq	0f
+	DECACHE_JPC
 	ldr	r2, =my_trace
 	blx	r2
-	msr	cpsr, r4
+0:	msr	cpsr, r4
 	ldmfd	sp!, {r0, r1, r2, r3, r4, ip, lr}	
 	.endm
 	
@@ -551,7 +554,7 @@
     .elseif dispatch_state == 4
 	DISPATCH_4
     .endif
-	TRACE
+@	TRACE
         moveq   pc, ip
 	ldrb	r1, [jpc, lr]
         bic     ip, ip, #7
@@ -561,7 +564,7 @@
 	.endm

 	.macro	DISPATCH_BYTECODE
-	TRACE
+@	TRACE
 @        ldrb    r1, [jpc, #2]
         ldr     ip, [dispatch, r0, lsl #2]
         ldrb    r2, [jpc, #1]
@@ -870,7 +873,7 @@

 	SLOW_ENTRY
 empty_entry:
-	ldrh	r3, [r0, #42]
+	ldrh	r3, [r0, #METHOD_SIZEOFPARAMETERS]
 	ldr	r1, [r2, #THREAD_JAVA_SP]
 	add	r1, r1, r3, lsl #2
 	str	r1, [r2, #THREAD_JAVA_SP]
@@ -879,7 +882,7 @@

 	FAST_ENTRY
 fast_empty_entry:
-	ldrh	r3, [r0, #42]
+	ldrh	r3, [r0, #METHOD_SIZEOFPARAMETERS]
 	ldr	r1, [thread, #THREAD_JAVA_SP]
 	add	r1, r1, r3, lsl #2
 	str	r1, [thread, #THREAD_JAVA_SP]
@@ -1081,7 +1084,7 @@

 	ldr	r1, [thread, #THREAD_STACK_SIZE]
 	ldr	r3, [thread, #THREAD_STACK_BASE]
-	add	r0, r9, #72
+	add	r0, r9, #ISTATE_NEXT_FRAME

 	rsb	r3, r1, r3
 	rsb	r3, r3, arm_sp
@@ -1104,7 +1107,7 @@
 	str	r5, [thread, #THREAD_LAST_JAVA_FP]
 	ldr	r5, [thread, #THREAD_JAVA_SP]
 	str	r5, [thread, #THREAD_LAST_JAVA_SP]
-	ldr	r11, [r11, #-72 + ISTATE_METHOD]
+	ldr	r11, [r11, #-ISTATE_NEXT_FRAME + ISTATE_METHOD]
 	cmp	r1, #0
 	bne	.fast_native_entry_exception
 	ldr	r5, [r11, #METHOD_SIGNATUREHANDLER]
@@ -1127,7 +1130,7 @@
 	ldr	r11, [thread, #THREAD_TOP_ZERO_FRAME]
 	ldr	r1, [thread, #THREAD_PENDING_EXC]
 	mov	r3, #0
-	ldr	r11, [r11, #-72 + ISTATE_METHOD]
+	ldr	r11, [r11, #-ISTATE_NEXT_FRAME + ISTATE_METHOD]
 	cmp	r1, #0
 	str	r3, [thread, #THREAD_LAST_JAVA_SP]
 	str	r3, [thread, #THREAD_LAST_JAVA_FP]
@@ -3353,12 +3356,12 @@
 	str	locals, [istate, #ISTATE_LOCALS]
   USEC	cmp	r3, lr
 	str	constpool, [istate, #ISTATE_CONSTANTS]
+	str	tmp1, [istate, #ISTATE_METHOD]
+ 	str	istate, [istate, #ISTATE_SELF_LINK]
   USEC	bcs	method_entry_freq_count_overflow
 	DISPATCH_NEXT
 	DISPATCH_NEXT
 	DISPATCH_NEXT
-	str	tmp1, [istate, #ISTATE_METHOD]
- 	str	istate, [istate, #ISTATE_SELF_LINK]
 @	mov	lr, #0
 @        str     lr, [istate, #ISTATE_PREV_LINK]
 @	str	lr, [istate, #ISTATE_CALLEE]