/*
 * Copyright (c) 1999-2007 Apple Inc.  All Rights Reserved.
 * 
 * @APPLE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */

#ifdef __x86_64__

/********************************************************************
 ********************************************************************
 **
 **  objc-msg-x86_64.s - x86-64 code to support objc messaging.
 **
 ********************************************************************
 ********************************************************************/

/********************************************************************
* Data used by the ObjC runtime.
*
********************************************************************/

.data
// Substitute receiver for messages sent to nil (usually also nil)
// id _objc_nilReceiver
.align 4
.private_extern __objc_nilReceiver
__objc_nilReceiver:
	.quad   0

// _objc_entryPoints and _objc_exitPoints are used by objc
// to get the critical regions for which method caches 
// cannot be garbage collected.

.private_extern	_objc_entryPoints
_objc_entryPoints:
	.quad	_cache_getImp
	.quad	_objc_msgSend
	.quad	_objc_msgSend_fpret
	.quad	_objc_msgSend_fp2ret
	.quad	_objc_msgSend_stret
	.quad	_objc_msgSendSuper
	.quad	_objc_msgSendSuper_stret
	.quad	_objc_msgSendSuper2
	.quad	_objc_msgSendSuper2_stret
	.quad	0

.private_extern	_objc_exitPoints
_objc_exitPoints:
	.quad	LExit_cache_getImp
	.quad	LExit_objc_msgSend
	.quad	LExit_objc_msgSend_fpret
	.quad	LExit_objc_msgSend_fp2ret
	.quad	LExit_objc_msgSend_stret
	.quad	LExit_objc_msgSendSuper
	.quad	LExit_objc_msgSendSuper_stret
	.quad	LExit_objc_msgSendSuper2
	.quad	LExit_objc_msgSendSuper2_stret
	.quad	0


/********************************************************************
* List every exit insn from every messenger for debugger use.
* Format:
* (
*   1 word instruction's address
*   1 word type (ENTER or FAST_EXIT or SLOW_EXIT or NIL_EXIT)
* )
* 1 word zero
*
* ENTER is the start of a dispatcher
* FAST_EXIT is method dispatch
* SLOW_EXIT is uncached method lookup
* NIL_EXIT is returning zero from a message sent to nil
* These must match objc-gdb.h.
********************************************************************/
	
#define ENTER     1
#define FAST_EXIT 2
#define SLOW_EXIT 3
#define NIL_EXIT  4

.section __DATA,__objc_msg_break
.globl _gdb_objc_messenger_breakpoints
_gdb_objc_messenger_breakpoints:
// contents populated by the macros below

.macro MESSENGER_START
4:
	.section __DATA,__objc_msg_break
	.quad 4b
	.quad ENTER
	.text
.endmacro
.macro MESSENGER_END_FAST
4:
	.section __DATA,__objc_msg_break
	.quad 4b
	.quad FAST_EXIT
	.text
.endmacro
.macro MESSENGER_END_SLOW
4:
	.section __DATA,__objc_msg_break
	.quad 4b
	.quad SLOW_EXIT
	.text
.endmacro
.macro MESSENGER_END_NIL
4:
	.section __DATA,__objc_msg_break
	.quad 4b
	.quad NIL_EXIT
	.text
.endmacro


/********************************************************************
 * Recommended multi-byte NOP instructions
 * (Intel 64 and IA-32 Architectures Software Developer's Manual Volume 2B)
 ********************************************************************/
#define nop1 .byte 0x90
#define nop2 .byte 0x66,0x90
#define nop3 .byte 0x0F,0x1F,0x00
#define nop4 .byte 0x0F,0x1F,0x40,0x00
#define nop5 .byte 0x0F,0x1F,0x44,0x00,0x00
#define nop6 .byte 0x66,0x0F,0x1F,0x44,0x00,0x00
#define nop7 .byte 0x0F,0x1F,0x80,0x00,0x00,0x00,0x00
#define nop8 .byte 0x0F,0x1F,0x84,0x00,0x00,0x00,0x00,0x00
#define nop9 .byte 0x66,0x0F,0x1F,0x84,0x00,0x00,0x00,0x00,0x00

	
/********************************************************************
 * Harmless branch prefix hint for instruction alignment
 ********************************************************************/
	
#define PN .byte 0x2e


/********************************************************************
 * Names for parameter registers.
 ********************************************************************/

#define a1  rdi
#define a1d edi
#define a1b dil
#define a2  rsi
#define a2d esi
#define a2b sil
#define a3  rdx
#define a3d edx
#define a4  rcx
#define a4d ecx
#define a5  r8
#define a5d r8d
#define a6  r9
#define a6d r9d


/********************************************************************
 * Names for relative labels
 * DO NOT USE THESE LABELS ELSEWHERE
 * Reserved labels: 5: 6: 7: 8: 9:
 ********************************************************************/
#define LCacheMiss 	5
#define LCacheMiss_f 	5f
#define LCacheMiss_b 	5b
#define LNilTestDone 	6
#define LNilTestDone_f 	6f
#define LNilTestDone_b 	6b
#define LNilTestSlow 	7
#define LNilTestSlow_f 	7f
#define LNilTestSlow_b 	7b
#define LGetIsaDone 	8
#define LGetIsaDone_f 	8f
#define LGetIsaDone_b 	8b
#define LGetIsaSlow 	9
#define LGetIsaSlow_f 	9f
#define LGetIsaSlow_b 	9b

/********************************************************************
 * Macro parameters
 ********************************************************************/

#define NORMAL 0
#define FPRET 1
#define FP2RET 2
#define GETIMP 3
#define STRET 4
#define SUPER 5
#define SUPER_STRET 6
#define SUPER2 7
#define SUPER2_STRET 8
	

/********************************************************************
 *
 * Structure definitions.
 *
 ********************************************************************/

// objc_super parameter to sendSuper
#define receiver 	0
#define class 		8

// Selected field offsets in class structure
// #define isa		0    USE GetIsa INSTEAD

// Method descriptor
#define method_name 	0
#define method_imp 	16

// typedef struct {
//	uint128_t floatingPointArgs[8];	// xmm0..xmm7
//	long linkageArea[4];		// r10, rax, ebp, ret
//	long registerArgs[6];		// a1..a6
//	long stackArgs[0];		// variable-size
// } *marg_list;
#define FP_AREA 0
#define LINK_AREA (FP_AREA+8*16)
#define REG_AREA (LINK_AREA+4*8)
#define STACK_AREA (REG_AREA+6*8)


//////////////////////////////////////////////////////////////////////
//
// ENTRY		functionName
//
// Assembly directives to begin an exported function.
//
// Takes: functionName - name of the exported function
//////////////////////////////////////////////////////////////////////

.macro ENTRY
	.text
	.globl	$0
	.align	6, 0x90
$0:
.endmacro

.macro STATIC_ENTRY
	.text
	.private_extern	$0
	.align	2, 0x90
$0:
.endmacro

//////////////////////////////////////////////////////////////////////
//
// END_ENTRY	functionName
//
// Assembly directives to end an exported function.  Just a placeholder,
// a close-parenthesis for ENTRY, until it is needed for something.
//
// Takes: functionName - name of the exported function
//////////////////////////////////////////////////////////////////////

.macro END_ENTRY
LExit$0:	
.endmacro


/* DWARF support
   These macros work for objc_msgSend variants and others that call
   CacheLookup/MethodTableLookup or SaveRegisters/RestoreRegisters
   without otherwise building a frame or clobbering callee-save registers

   The macros build appropriate FDEs and tie them to the CIE.
*/

#define DW_CFA_offset 0x80
#define DW_CFA_restore 0xc0
#define DW_CFA_advance_loc4 0x4
#define DW_CFA_same_value 0x8
#define DW_CFA_def_cfa 0xc
#define DW_CFA_def_cfa_register 0xd
#define DW_CFA_def_cfa_offset 0xe
#define DW_CFA_offset_extended_sf 0x11
#define DW_CFA_def_cfa_offset_sf 0x13
#define DW_rax 0
#define DW_rdx 1
#define DW_rcx 2
#define DW_rsi 4
#define DW_rdi 5
#define DW_rbp 6
#define DW_rsp 7
#define DW_r8  8
#define DW_r9  9
#define DW_r10 10
#define DW_ra 16
#define DW_xmm0 17
#define DW_xmm1 18
#define DW_xmm2 19
#define DW_xmm3 20
#define DW_xmm4 21
#define DW_xmm5 22
#define DW_xmm6 23
#define DW_xmm7 24
#define DW_a1  DW_rdi
#define DW_a2  DW_rsi
#define DW_a3  DW_rdx
#define DW_a4  DW_rcx
#define DW_a5  DW_r8
#define DW_a6  DW_r9

// CIE
// 8-byte data multiplier
// 1-byte insn multiplier
// PC-relative everything
// No prologue
	
	.section __TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support
CIE:
	.set	L$set$0,LECIE1-LSCIE1
	.long	L$set$0	# Length of Common Information Entry
LSCIE1:
	.long	0	# CIE Identifier Tag
	.byte	0x3	# CIE Version
	.ascii	"zPR\0"	# CIE Augmentation: size + personality + FDE encoding
	.byte	0x1	# uleb128 0x1; CIE Code Alignment Factor
	.byte	0x78	# sleb128 -0x8; CIE Data Alignment Factor
	.byte	0x10	# CIE RA Column
	.byte	0x6	# uleb128 0x1; Augmentation size
	// Personality augmentation
	.byte	0x9b
	.long	___objc_personality_v0+4@GOTPCREL
	// FDE-encoding augmentation
	.byte	0x10
	// Prefix instructions
	// CFA is %rsp+8
	.byte	DW_CFA_def_cfa
	.byte	DW_rsp
	.byte	8
	// RA is at 0(%rsp) aka 1*-8(CFA)
	.byte	DW_CFA_offset | DW_ra
	.byte	1
	
	.align 3
LECIE1:


.macro EMIT_FDE

	.section __TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support
	
// FDE header
.globl $0.eh
$0.eh:
LSFDE$0:
	.set 	LLENFDE$0, LEFDE$0-LASFDE$0
	.long 	LLENFDE$0		# FDE Length
LASFDE$0:
	.long 	LASFDE$0-CIE		# FDE CIE offset
	.quad	L_dw_start_$0-.		# FDE address start
	.quad	L_dw_len_$0		# FDE address range
	.byte	0x0			# uleb128 0x0; Augmentation size

	// DW_START: set by CIE

.if $1 == 1
	// Save/RestoreRegisters or MethodTableLookup

	// enter
	.byte 	DW_CFA_advance_loc4
	.long	L_dw_enter_$0 - L_dw_start_$0
	.byte   DW_CFA_def_cfa_offset
	.byte   16
	.byte	DW_CFA_offset | DW_rbp	// rbp => 2*-8(CFA)
	.byte	2
	.byte	DW_CFA_def_cfa_register	// CFA = rbp+16 (offset unchanged)
	.byte	DW_rbp
	
	// leave
	.byte 	DW_CFA_advance_loc4
	.long	L_dw_leave_$0 - L_dw_enter_$0

	.byte 	DW_CFA_same_value	// rbp = original value
	.byte	DW_rbp
	.byte	DW_CFA_def_cfa		// CFA = rsp+8
	.byte	DW_rsp
	.byte	8

.endif

	.align 3
LEFDE$0:
	.text
	
.endmacro


// Start of function
.macro DW_START
L_dw_start_$0:
.endmacro
	
// After `enter` in SaveRegisters
.macro DW_ENTER
L_dw_enter_$0:	
.endmacro

// After `leave` in RestoreRegisters
.macro DW_LEAVE
L_dw_leave_$0:
.endmacro
	
// End of function
// $1 == 1 iff you called MethodTableLookup or Save/RestoreRegsters
.macro DW_END
	.set 	L_dw_len_$0, . - L_dw_start_$0
	EMIT_FDE $0, $1
.endmacro


/////////////////////////////////////////////////////////////////////
//
// SaveRegisters caller
//
// Pushes a stack frame and saves all registers that might contain
// parameter values.
//
// On entry:	%0 = caller's symbol name for DWARF
//		stack = ret
//
// On exit: 
//		%rsp is 16-byte aligned
//	
/////////////////////////////////////////////////////////////////////

.macro SaveRegisters
	// These instructions must match the DWARF data in EMIT_FDE.
	
	enter	$$0x80+8, $$0		// +8 for alignment
	DW_ENTER $0

	movdqa	%xmm0, -0x80(%rbp)
	push	%rax			// might be xmm parameter count
	movdqa	%xmm1, -0x70(%rbp)
	push	%a1
	movdqa	%xmm2, -0x60(%rbp)
	push	%a2
	movdqa	%xmm3, -0x50(%rbp)
	push	%a3
	movdqa	%xmm4, -0x40(%rbp)
	push	%a4
	movdqa	%xmm5, -0x30(%rbp)
	push	%a5
	movdqa	%xmm6, -0x20(%rbp)
	push	%a6
	movdqa	%xmm7, -0x10(%rbp)
	
	// These instructions must match the DWARF data in EMIT_FDE.
.endmacro

/////////////////////////////////////////////////////////////////////
//
// RestoreRegisters
//
// Pops a stack frame pushed by SaveRegisters
//
// On entry:	$0 = caller's symbol name for DWARF
//		%rbp unchanged since SaveRegisters
//
// On exit: 
//		stack = ret
//	
/////////////////////////////////////////////////////////////////////

.macro RestoreRegisters
	// These instructions must match the DWARF data in EMIT_FDE.

	movdqa	-0x80(%rbp), %xmm0
	pop	%a6
	movdqa	-0x70(%rbp), %xmm1
	pop	%a5
	movdqa	-0x60(%rbp), %xmm2
	pop	%a4
	movdqa	-0x50(%rbp), %xmm3
	pop	%a3
	movdqa	-0x40(%rbp), %xmm4
	pop	%a2
	movdqa	-0x30(%rbp), %xmm5
	pop	%a1
	movdqa	-0x20(%rbp), %xmm6
	pop	%rax
	movdqa	-0x10(%rbp), %xmm7
	
	leave
	DW_LEAVE $0

	// These instructions must match the DWARF data in EMIT_FDE.
.endmacro


/////////////////////////////////////////////////////////////////////
//
// CacheLookup	return-type, caller
//
// Locate the implementation for a class in a selector's method cache.
//
// Takes: 
//	  $0 = NORMAL, FPRET, FP2RET, STRET, SUPER, SUPER_STRET, SUPER2, SUPER2_STRET, GETIMP
//	  a2 or a3 (STRET) = selector a.k.a. cache
//	  r11 = class to search
//
// On exit: r10 clobbered
//	    (found) calls or returns IMP, eq/ne/r11 set for forwarding
//	    (not found) jumps to LCacheMiss, class still in r11
//
/////////////////////////////////////////////////////////////////////

.macro CacheHit

	// CacheHit must always be preceded by a not-taken `jne` instruction
	// in order to set the correct flags for _objc_msgForward_impcache.

	// r10 = found bucket
	
.if $0 == GETIMP
	movq	8(%r10), %rax		// return imp
	leaq	__objc_msgSend_uncached_impcache(%rip), %r11
	cmpq	%rax, %r11
	jne 4f
	xorl	%eax, %eax		// don't return msgSend_uncached
4:	ret
.elseif $0 == NORMAL  ||  $0 == FPRET  ||  $0 == FP2RET
	// eq already set for forwarding by `jne`
	MESSENGER_END_FAST
	jmp	*8(%r10)		// call imp
	
.elseif $0 == SUPER
	movq	receiver(%a1), %a1	// load real receiver
	cmp	%r10, %r10		// set eq for non-stret forwarding
	MESSENGER_END_FAST
	jmp	*8(%r10)		// call imp
	
.elseif $0 == SUPER2
	movq	receiver(%a1), %a1	// load real receiver
	cmp	%r10, %r10		// set eq for non-stret forwarding
	MESSENGER_END_FAST
	jmp	*8(%r10)		// call imp
	
.elseif $0 == STRET
	test	%r10, %r10		// set ne for stret forwarding
	MESSENGER_END_FAST
	jmp	*8(%r10)		// call imp
	
.elseif $0 == SUPER_STRET
	movq	receiver(%a2), %a2	// load real receiver
	test	%r10, %r10		// set ne for stret forwarding
	MESSENGER_END_FAST
	jmp	*8(%r10)		// call imp
	
.elseif $0 == SUPER2_STRET
	movq	receiver(%a2), %a2	// load real receiver
	test	%r10, %r10		// set ne for stret forwarding
	MESSENGER_END_FAST
	jmp	*8(%r10)		// call imp
.else
.abort oops
.endif
	
.endmacro

	
.macro	CacheLookup
.if $0 != STRET  &&  $0 != SUPER_STRET  &&  $0 != SUPER2_STRET
	movq	%a2, %r10		// r10 = _cmd
.else
	movq	%a3, %r10		// r10 = _cmd
.endif
	andl	24(%r11), %r10d		// r10 = _cmd & class->cache.mask
	shlq	$$4, %r10		// r10 = offset = (_cmd & mask)<<4
	addq	16(%r11), %r10		// r10 = class->cache.buckets + offset

.if $0 != STRET  &&  $0 != SUPER_STRET  &&  $0 != SUPER2_STRET
	cmpq	(%r10), %a2		// if (bucket->sel != _cmd)
.else
	cmpq	(%r10), %a3		// if (bucket->sel != _cmd)
.endif
	jne 	1f			//     scan more
	// CacheHit must always be preceded by a not-taken `jne` instruction
	CacheHit $0			// call or return imp

1:
	// loop
	cmpq	$$0, (%r10)
	je	LCacheMiss_f		// if (bucket->sel == 0) cache miss
	cmpq	16(%r11), %r10
	je	3f			// if (bucket == cache->buckets) wrap

	subq	$$16, %r10		// bucket--
.if $0 != STRET  &&  $0 != SUPER_STRET  &&  $0 != SUPER2_STRET
	cmpq	(%r10), %a2		// if (bucket->sel != _cmd)
.else
	cmpq	(%r10), %a3		// if (bucket->sel != _cmd)
.endif
	jne 	1b			//     scan more
	// CacheHit must always be preceded by a not-taken `jne` instruction
	CacheHit $0			// call or return imp

3:
	// wrap
	movl	24(%r11), %r10d		// r10 = mask a.k.a. last bucket index
	shlq	$$4, %r10		// r10 = offset = mask<<4
	addq	16(%r11), %r10		// r10 = &cache->buckets[mask]
	jmp 	2f

	// clone scanning loop to crash instead of hang when cache is corrupt

1:
	// loop
	cmpq	$$0, (%r10)
	je	LCacheMiss_f		// if (bucket->sel == 0) cache miss
	cmpq	16(%r11), %r10
	je	3f			// if (bucket == cache->buckets) wrap

	subq	$$16, %r10		// bucket--
2:	
.if $0 != STRET  &&  $0 != SUPER_STRET  &&  $0 != SUPER2_STRET
	cmpq	(%r10), %a2		// if (bucket->sel != _cmd)
.else
	cmpq	(%r10), %a3		// if (bucket->sel != _cmd)
.endif
	jne 	1b			//     scan more
	// CacheHit must always be preceded by a not-taken `jne` instruction
	CacheHit $0			// call or return imp

3:
	// double wrap - busted
.if $0 == STRET  ||  $0 == SUPER_STRET  ||  $0 == SUPER2_STRET
	movq	%a2, %a1
	movq	%a3, %a2
.elseif $0 == GETIMP
	movq	$$0, %a1
.endif
				// a1 = receiver
				// a2 = SEL
	movq	%r11, %a3	// a3 = isa
	movq	%r10, %a4	// a4 = bucket
.if $0 == GETIMP
	jmp	_cache_getImp_corrupt_cache_error
.else
	jmp	_objc_msgSend_corrupt_cache_error
.endif
.endmacro


/////////////////////////////////////////////////////////////////////
//
// MethodTableLookup classRegister, selectorRegister, caller
//
// Takes:	$0 = class to search (a1 or a2 or r10 ONLY)
//		$1 = selector to search for (a2 or a3 ONLY)
//		$2 = caller's symbol name for DWARF
// 		r11 = class to search
//
// On exit: imp in %r11
//
/////////////////////////////////////////////////////////////////////
.macro MethodTableLookup

	MESSENGER_END_SLOW
	
	SaveRegisters $2

	// _class_lookupMethodAndLoadCache3(receiver, selector, class)

	movq	$0, %a1
	movq	$1, %a2
	movq	%r11, %a3
	call	__class_lookupMethodAndLoadCache3

	// IMP is now in %rax
	movq	%rax, %r11

	RestoreRegisters $2

.endmacro

/////////////////////////////////////////////////////////////////////
//
// GetIsaFast return-type
// GetIsaSupport return-type
//
// Sets r11 = obj->isa. Consults the tagged isa table if necessary.
//
// Takes:	$0 = NORMAL or FPRET or FP2RET or STRET
//		a1 or a2 (STRET) = receiver
//
// On exit: 	r11 = receiver->isa
//		r10 is clobbered
//
/////////////////////////////////////////////////////////////////////

.macro GetIsaFast
.if $0 != STRET
	testb	$$1, %a1b
	PN
	jnz	LGetIsaSlow_f
	movq	(%a1), %r11
.else
	testb	$$1, %a2b
	PN
	jnz	LGetIsaSlow_f
	movq	(%a2), %r11
.endif
LGetIsaDone:	
.endmacro

.macro GetIsaSupport2
LGetIsaSlow:
	leaq	_objc_debug_taggedpointer_classes(%rip), %r11
.if $0 != STRET
	movl	%a1d, %r10d
.else
	movl	%a2d, %r10d
.endif
	andl	$$0xF, %r10d
	movq	(%r11, %r10, 8), %r11	// read isa from table
.endmacro
	
.macro GetIsaSupport
	GetIsaSupport2 $0
	jmp	LGetIsaDone_b
.endmacro

.macro GetIsa
	GetIsaFast $0
	jmp	LGetIsaDone_f
	GetIsaSupport2 $0
LGetIsaDone:
.endmacro

	
/////////////////////////////////////////////////////////////////////
//
// NilTest return-type
//
// Takes:	$0 = NORMAL or FPRET or FP2RET or STRET
//		%a1 or %a2 (STRET) = receiver
//
// On exit: 	Loads non-nil receiver in %a1 or %a2 (STRET), or returns zero.
//
// NilTestSupport return-type
//
// Takes:	$0 = NORMAL or FPRET or FP2RET or STRET
//		%a1 or %a2 (STRET) = receiver
//
// On exit: 	Loads non-nil receiver in %a1 or %a2 (STRET), or returns zero.
//
/////////////////////////////////////////////////////////////////////

.macro NilTest
.if $0 == SUPER  ||  $0 == SUPER_STRET
	error super dispatch does not test for nil
.endif

.if $0 != STRET
	testq	%a1, %a1
.else
	testq	%a2, %a2
.endif
	PN
	jz	LNilTestSlow_f
LNilTestDone:
.endmacro

.macro NilTestSupport
	.align 3
LNilTestSlow:
.if $0 != STRET
	movq	__objc_nilReceiver(%rip), %a1
	testq	%a1, %a1	// if (receiver != nil)
.else
	movq	__objc_nilReceiver(%rip), %a2
	testq	%a2, %a2	// if (receiver != nil)
.endif
	jne	LNilTestDone_b	//   send to new receiver

.if $0 == FPRET
	fldz
.elseif $0 == FP2RET
	fldz
	fldz
.endif
.if $0 == STRET
	movq	%rdi, %rax
.else
	xorl	%eax, %eax
	xorl	%edx, %edx
	xorps	%xmm0, %xmm0
	xorps	%xmm1, %xmm1
.endif
	MESSENGER_END_NIL
	ret
.endmacro


/********************************************************************
 * IMP cache_getImp(Class cls, SEL sel)
 *
 * On entry:	a1 = class whose cache is to be searched
 *		a2 = selector to search for
 *
 * If found, returns method implementation.
 * If not found, returns NULL.
 ********************************************************************/

	STATIC_ENTRY _cache_getImp
	DW_START _cache_getImp

// do lookup
	movq	%a1, %r11		// move class to r11 for CacheLookup
	CacheLookup GETIMP		// returns IMP on success

LCacheMiss:
// cache miss, return nil
	xorl	%eax, %eax
	ret

LGetImpExit:
	DW_END		_cache_getImp, 0
	END_ENTRY 	_cache_getImp


/********************************************************************
 *
 * id objc_msgSend(id self, SEL	_cmd,...);
 *
 ********************************************************************/
	
	.data
	.align 3
	.globl _objc_debug_taggedpointer_classes
_objc_debug_taggedpointer_classes:
	.fill 16, 8, 0

	ENTRY	_objc_msgSend
	DW_START _objc_msgSend
	MESSENGER_START

	NilTest	NORMAL

	GetIsaFast NORMAL		// r11 = self->isa
	CacheLookup NORMAL		// calls IMP on success

	NilTestSupport	NORMAL

	GetIsaSupport	NORMAL

// cache miss: go search the method lists
LCacheMiss:
	// isa still in r11
	MethodTableLookup %a1, %a2, _objc_msgSend	// r11 = IMP
	cmp	%r11, %r11		// set eq (nonstret) for forwarding
	jmp	*%r11			// goto *imp

	DW_END 		_objc_msgSend, 1
	END_ENTRY	_objc_msgSend

	
	ENTRY _objc_msgSend_fixup
	int3
	END_ENTRY _objc_msgSend_fixup

	
	STATIC_ENTRY _objc_msgSend_fixedup
	// Load _cmd from the message_ref
	movq	8(%a2), %a2
	jmp	_objc_msgSend
	END_ENTRY _objc_msgSend_fixedup

	
/********************************************************************
 *
 * id objc_msgSendSuper(struct objc_super *super, SEL _cmd,...);
 *
 * struct objc_super {
 *		id	receiver;
 *		Class	class;
 * };
 ********************************************************************/
	
	ENTRY	_objc_msgSendSuper
	DW_START _objc_msgSendSuper
	MESSENGER_START
	
// search the cache (objc_super in %a1)
	movq	class(%a1), %r11	// class = objc_super->class
	CacheLookup SUPER		// calls IMP on success

// cache miss: go search the method lists
LCacheMiss:
	// class still in r11
	movq	receiver(%a1), %r10
	MethodTableLookup %r10, %a2, _objc_msgSendSuper	// r11 = IMP
	movq	receiver(%a1), %a1	// load real receiver
	cmp	%r11, %r11		// set eq (nonstret) for forwarding
	jmp	*%r11			// goto *imp
	
	DW_END 		_objc_msgSendSuper, 1
	END_ENTRY	_objc_msgSendSuper


/********************************************************************
 * id objc_msgSendSuper2
 ********************************************************************/

	ENTRY _objc_msgSendSuper2
	DW_START _objc_msgSendSuper2
	MESSENGER_START
	
	// objc_super->class is superclass of class to search
	
// search the cache (objc_super in %a1)
	movq	class(%a1), %r11	// cls = objc_super->class
	movq	8(%r11), %r11		// cls = class->superclass
	CacheLookup SUPER2		// calls IMP on success

// cache miss: go search the method lists
LCacheMiss:
	// superclass still in r11
	movq	receiver(%a1), %r10
	MethodTableLookup %r10, %a2, _objc_msgSendSuper2	// r11 = IMP
	movq	receiver(%a1), %a1	// load real receiver
	cmp	%r11, %r11		// set eq (nonstret) for forwarding
	jmp	*%r11			// goto *imp
	
	DW_END 		_objc_msgSendSuper2, 1
	END_ENTRY	_objc_msgSendSuper2

	
	ENTRY _objc_msgSendSuper2_fixup
	int3
	END_ENTRY _objc_msgSendSuper2_fixup

	
	STATIC_ENTRY _objc_msgSendSuper2_fixedup
	// Load _cmd from the message_ref
	movq	8(%a2), %a2
	jmp 	_objc_msgSendSuper2
	END_ENTRY _objc_msgSendSuper2_fixedup


/********************************************************************
 *
 * double objc_msgSend_fpret(id self, SEL _cmd,...);
 * Used for `long double` return only. `float` and `double` use objc_msgSend.
 *
 ********************************************************************/

	ENTRY	_objc_msgSend_fpret
	DW_START _objc_msgSend_fpret
	MESSENGER_START
	
	NilTest	FPRET

	GetIsaFast FPRET		// r11 = self->isa
	CacheLookup FPRET		// calls IMP on success

	NilTestSupport	FPRET

	GetIsaSupport	FPRET

// cache miss: go search the method lists
LCacheMiss:
	// isa still in r11
	MethodTableLookup %a1, %a2, _objc_msgSend_fpret	// r11 = IMP
	cmp	%r11, %r11		// set eq (nonstret) for forwarding
	jmp	*%r11			// goto *imp

	DW_END 		_objc_msgSend_fpret, 1
	END_ENTRY	_objc_msgSend_fpret

	
	ENTRY _objc_msgSend_fpret_fixup
	int3
	END_ENTRY _objc_msgSend_fpret_fixup

	
	STATIC_ENTRY _objc_msgSend_fpret_fixedup
	// Load _cmd from the message_ref
	movq	8(%a2), %a2
	jmp	_objc_msgSend_fpret
	END_ENTRY _objc_msgSend_fpret_fixedup


/********************************************************************
 *
 * double objc_msgSend_fp2ret(id self, SEL _cmd,...);
 * Used for `complex long double` return only.
 *
 ********************************************************************/

	ENTRY	_objc_msgSend_fp2ret
	DW_START _objc_msgSend_fp2ret
	MESSENGER_START
	
	NilTest	FP2RET

	GetIsaFast FP2RET		// r11 = self->isa
	CacheLookup FP2RET		// calls IMP on success

	NilTestSupport	FP2RET

	GetIsaSupport 	FP2RET
	
// cache miss: go search the method lists
LCacheMiss:
	// isa still in r11
	MethodTableLookup %a1, %a2, _objc_msgSend_fp2ret	// r11 = IMP
	cmp	%r11, %r11		// set eq (nonstret) for forwarding
	jmp	*%r11			// goto *imp

	DW_END 		_objc_msgSend_fp2ret, 1
	END_ENTRY	_objc_msgSend_fp2ret


	ENTRY _objc_msgSend_fp2ret_fixup
	int3
	END_ENTRY _objc_msgSend_fp2ret_fixup

	
	STATIC_ENTRY _objc_msgSend_fp2ret_fixedup
	// Load _cmd from the message_ref
	movq	8(%a2), %a2
	jmp	_objc_msgSend_fp2ret
	END_ENTRY _objc_msgSend_fp2ret_fixedup


/********************************************************************
 *
 * void	objc_msgSend_stret(void *st_addr, id self, SEL _cmd, ...);
 *
 * objc_msgSend_stret is the struct-return form of msgSend.
 * The ABI calls for %a1 to be used as the address of the structure
 * being returned, with the parameters in the succeeding locations.
 *
 * On entry:	%a1 is the address where the structure is returned,
 *		%a2 is the message receiver,
 *		%a3 is the selector
 ********************************************************************/

	ENTRY	_objc_msgSend_stret
	DW_START _objc_msgSend_stret
	MESSENGER_START
	
	NilTest	STRET

	GetIsaFast STRET		// r11 = self->isa
	CacheLookup STRET		// calls IMP on success

	NilTestSupport	STRET

	GetIsaSupport	STRET

// cache miss: go search the method lists
LCacheMiss:
	// isa still in r11
	MethodTableLookup %a2, %a3, _objc_msgSend_stret	// r11 = IMP
	test	%r11, %r11		// set ne (stret) for forward; r11!=0
	jmp	*%r11			// goto *imp

	DW_END 		_objc_msgSend_stret, 1
	END_ENTRY	_objc_msgSend_stret


	ENTRY _objc_msgSend_stret_fixup
	int3
	END_ENTRY _objc_msgSend_stret_fixup


	STATIC_ENTRY _objc_msgSend_stret_fixedup
	// Load _cmd from the message_ref
	movq	8(%a3), %a3
	jmp	_objc_msgSend_stret
	END_ENTRY _objc_msgSend_stret_fixedup


/********************************************************************
 *
 * void objc_msgSendSuper_stret(void *st_addr, struct objc_super *super, SEL _cmd, ...);
 *
 * struct objc_super {
 *		id	receiver;
 *		Class	class;
 * };
 *
 * objc_msgSendSuper_stret is the struct-return form of msgSendSuper.
 * The ABI calls for (sp+4) to be used as the address of the structure
 * being returned, with the parameters in the succeeding registers.
 *
 * On entry:	%a1 is the address where the structure is returned,
 *		%a2 is the address of the objc_super structure,
 *		%a3 is the selector
 *
 ********************************************************************/

	ENTRY	_objc_msgSendSuper_stret
	DW_START _objc_msgSendSuper_stret
	MESSENGER_START
	
// search the cache (objc_super in %a2)
	movq	class(%a2), %r11	// class = objc_super->class
	CacheLookup SUPER_STRET		// calls IMP on success

// cache miss: go search the method lists
LCacheMiss:
	// class still in r11
	movq	receiver(%a2), %r10
	MethodTableLookup %r10, %a3, _objc_msgSendSuper_stret	// r11 = IMP
	movq	receiver(%a2), %a2	// load real receiver
	test	%r11, %r11		// set ne (stret) for forward; r11!=0
	jmp	*%r11			// goto *imp

	DW_END 		_objc_msgSendSuper_stret, 1
	END_ENTRY	_objc_msgSendSuper_stret


/********************************************************************
 * id objc_msgSendSuper2_stret
 ********************************************************************/

	ENTRY	_objc_msgSendSuper2_stret
	DW_START _objc_msgSendSuper2_stret
	MESSENGER_START
	
// search the cache (objc_super in %a2)
	movq	class(%a2), %r11	// class = objc_super->class
	movq	8(%r11), %r11		// class = class->superclass
	CacheLookup SUPER2_STRET	// calls IMP on success

// cache miss: go search the method lists
LCacheMiss:
	// superclass still in r11
	movq	receiver(%a2), %r10
	MethodTableLookup %r10, %a3, _objc_msgSendSuper2_stret	// r11 = IMP
	movq	receiver(%a2), %a2	// load real receiver
	test	%r11, %r11		// set ne (stret) for forward; r11!=0
	jmp	*%r11			// goto *imp

	DW_END 		_objc_msgSendSuper2_stret, 1
	END_ENTRY	_objc_msgSendSuper2_stret

	
	ENTRY _objc_msgSendSuper2_stret_fixup
	int3
	END_ENTRY _objc_msgSendSuper2_stret_fixup

	
	STATIC_ENTRY _objc_msgSendSuper2_stret_fixedup
	// Load _cmd from the message_ref
	movq	8(%a3), %a3
	jmp	_objc_msgSendSuper2_stret
	END_ENTRY _objc_msgSendSuper2_stret_fixedup


/********************************************************************
 *
 * _objc_msgSend_uncached_impcache
 * _objc_msgSend_uncached
 * _objc_msgSend_stret_uncached
 * 
 * Used to erase method cache entries in-place by 
 * bouncing them to the uncached lookup.
 *
 ********************************************************************/
	
	STATIC_ENTRY __objc_msgSend_uncached_impcache
	// Method cache version

	// THIS IS NOT A CALLABLE C FUNCTION
	// Out-of-band condition register is NE for stret, EQ otherwise.
	// Out-of-band r11 is the searched class

	MESSENGER_START
	nop
	MESSENGER_END_SLOW
	
	jne	__objc_msgSend_stret_uncached
	jmp	__objc_msgSend_uncached

	END_ENTRY __objc_msgSend_uncached_impcache


	STATIC_ENTRY __objc_msgSend_uncached
	DW_START __objc_msgSend_uncached

	// THIS IS NOT A CALLABLE C FUNCTION
	// Out-of-band r11 is the searched class

	// r11 is already the class to search
	MethodTableLookup %a1, %a2, __objc_msgSend_uncached	// r11 = IMP
	cmp	%r11, %r11		// set eq (nonstret) for forwarding
	jmp	*%r11			// goto *imp

	DW_END __objc_msgSend_uncached, 1
	END_ENTRY __objc_msgSend_uncached

	
	STATIC_ENTRY __objc_msgSend_stret_uncached
	DW_START __objc_msgSend_stret_uncached
	// THIS IS NOT A CALLABLE C FUNCTION
	// Out-of-band r11 is the searched class

	// r11 is already the class to search
	MethodTableLookup %a2, %a3, __objc_msgSend_stret_uncached  // r11 = IMP
	test	%r11, %r11		// set ne (stret) for forward; r11!=0
	jmp	*%r11			// goto *imp

	DW_END __objc_msgSend_stret_uncached, 1
	END_ENTRY __objc_msgSend_stret_uncached

	
/********************************************************************
 *
 * id _objc_msgForward(id self, SEL _cmd,...);
 *
 ********************************************************************/

// _FwdSel is @selector(forward::), set up in map_images().
// ALWAYS dereference _FwdSel to get to "forward::" !!
	.data
	.align 3
	.private_extern _FwdSel
_FwdSel: .quad 0

	.cstring
	.align 3
LUnkSelStr: .ascii "Does not recognize selector %s (while forwarding %s)\0"

	.data
	.align 3
	.private_extern __objc_forward_handler
__objc_forward_handler:	.quad 0

	.data
	.align 3
	.private_extern __objc_forward_stret_handler
__objc_forward_stret_handler:	.quad 0


	STATIC_ENTRY	__objc_msgForward_impcache
	// Method cache version

	// THIS IS NOT A CALLABLE C FUNCTION
	// Out-of-band condition register is NE for stret, EQ otherwise.

	MESSENGER_START
	nop
	MESSENGER_END_SLOW
	
	jne	__objc_msgForward_stret
	jmp	__objc_msgForward

	END_ENTRY	__objc_msgForward_impcache
	
	
	ENTRY	__objc_msgForward
	// Non-stret version

	// Call user handler, if any
	movq	__objc_forward_handler(%rip), %r11
	testq	%r11, %r11		// if (handler == NULL)
	je	1f			//   skip handler
	jmp	*%r11			// else goto handler
1:	
	// No user handler

	// Die if forwarding "forward::"
	cmpq	%a2, _FwdSel(%rip)
	je	LMsgForwardError

	// Record current return address. It will be copied elsewhere in 
	// the marg_list because this location is needed for register args
	movq	(%rsp), %r11

	// Push stack frame
	// Space for: fpArgs + regArgs + linkage - ret (already on stack)
	subq	$ 8*16 + 6*8 + (4-1)*8, %rsp

	// Save return address in linkage area.
	movq	%r11, 16+LINK_AREA(%rsp)
	
	// Save parameter registers
	movq	%a1,  0+REG_AREA(%rsp)
	movq	%a2,  8+REG_AREA(%rsp)
	movq	%a3, 16+REG_AREA(%rsp)
	movq	%a4, 24+REG_AREA(%rsp)
	movq	%a5, 32+REG_AREA(%rsp)
	movq	%a6, 40+REG_AREA(%rsp)

	// Save side parameter registers
	// movq	%r10, 0+LINK_AREA(%rsp)	// static chain pointer == Pascal
	movq	%rax, 8+LINK_AREA(%rsp)	// xmm count
	// 16+LINK_AREA is return address

	// Save xmm registers
	movdqa	%xmm0, 0+FP_AREA(%rsp)
	movdqa	%xmm1, 16+FP_AREA(%rsp)
	movdqa	%xmm2, 32+FP_AREA(%rsp)
	movdqa	%xmm3, 48+FP_AREA(%rsp)
	movdqa	%xmm4, 64+FP_AREA(%rsp)
	movdqa	%xmm5, 80+FP_AREA(%rsp)
	movdqa	%xmm6, 96+FP_AREA(%rsp)
	movdqa	%xmm7, 112+FP_AREA(%rsp)

	// Call [receiver forward:sel :margs]
	movq	%rsp, %a4		// marg_list
	movq	%a2, %a3		// sel
	movq	_FwdSel(%rip), %a2	// forward::
	// %a1 is already the receiver

	call	_objc_msgSend
	
	// Retrieve return address from linkage area
	movq	16+LINK_AREA(%rsp), %r11
	// Pop stack frame
	addq	$ 8*16 + 6*8 + (4-1)*8, %rsp
	// Put return address back
	movq	%r11, (%rsp)
	ret

LMsgForwardError:
	// Tail-call __objc_error(receiver, "unknown selector %s %s", "forward::", forwardedSel)
	// %a1 is already the receiver
	movq	%a3, %a4		// the forwarded selector
	leaq	LUnkSelStr(%rip), %a2	// "unknown selector %s %s"
	movq	_FwdSel(%rip), %a3	// forward::
	jmp	___objc_error		// never returns

	END_ENTRY	__objc_msgForward


	ENTRY	__objc_msgForward_stret
	// Struct-return version
	
	// Call user handler, if any
	movq	__objc_forward_stret_handler(%rip), %r11
	testq	%r11, %r11		// if (handler == NULL)
	je	1f			//   skip handler
	jmp	*%r11			// else goto handler
1:	
	// No user handler
	// Die if forwarding "forward::"
	cmpq	%a3, _FwdSel(%rip)
	je	LMsgForwardStretError

	// Record current return address. It will be copied elsewhere in 
	// the marg_list because this location is needed for register args
	movq	(%rsp), %r11

	// Push stack frame
	// Space for: fpArgs + regArgs + linkage - ret (already on stack)
	subq	$ 8*16 + 6*8 + (4-1)*8, %rsp

	// Save return address in linkage area.
	movq	%r11, 16+LINK_AREA(%rsp)
	
	// Save parameter registers
	movq	%a1,  0+REG_AREA(%rsp)  // note: used again below
	movq	%a2,  8+REG_AREA(%rsp)
	movq	%a3, 16+REG_AREA(%rsp)
	movq	%a4, 24+REG_AREA(%rsp)
	movq	%a5, 32+REG_AREA(%rsp)
	movq	%a6, 40+REG_AREA(%rsp)

	// Save side parameter registers
	// movq	%r10, 0+LINK_AREA(%rsp)	// static chain pointer == Pascal
	movq	%rax, 8+LINK_AREA(%rsp)	// xmm count
	// 16+LINK_AREA is return address

	// Save xmm registers
	movdqa	%xmm0, 0+FP_AREA(%rsp)
	movdqa	%xmm1, 16+FP_AREA(%rsp)
	movdqa	%xmm2, 32+FP_AREA(%rsp)
	movdqa	%xmm3, 48+FP_AREA(%rsp)
	movdqa	%xmm4, 64+FP_AREA(%rsp)
	movdqa	%xmm5, 80+FP_AREA(%rsp)
	movdqa	%xmm6, 96+FP_AREA(%rsp)
	movdqa	%xmm7, 112+FP_AREA(%rsp)

	// Call [receiver forward:sel :margs]
	movq	%a2, %a1		// receiver
	movq	_FwdSel(%rip), %a2	// forward::
	// %a3 is already the selector
	movq	%rsp, %a4		// marg_list

	call	_objc_msgSend		// forward:: is NOT struct-return
	
	// Set return value register to the passed-in struct address
	movq	0+REG_AREA(%rsp), %rax
	// Retrieve return address from linkage area
	movq	16+LINK_AREA(%rsp), %r11
	// Pop stack frame
	addq	$ 8*16 + 6*8 + (4-1)*8, %rsp
	// Put return address back
	movq	%r11, (%rsp)
	ret

LMsgForwardStretError:
	// Tail-call __objc_error(receiver, "unknown selector %s %s", "forward::", forwardedSel)
	// %a4 is already the forwarded selector
	movq	%a2, %a1		// receiver
	leaq	LUnkSelStr(%rip), %a2	// "unknown selector %s %s"
	movq	_FwdSel(%rip), %a3	// forward::
	jmp	___objc_error		// never returns

	END_ENTRY	__objc_msgForward_stret


	ENTRY _objc_msgSend_debug
	jmp	_objc_msgSend
	END_ENTRY _objc_msgSend_debug

	ENTRY _objc_msgSendSuper2_debug
	jmp	_objc_msgSendSuper2
	END_ENTRY _objc_msgSendSuper2_debug

	ENTRY _objc_msgSend_stret_debug
	jmp	_objc_msgSend_stret
	END_ENTRY _objc_msgSend_stret_debug

	ENTRY _objc_msgSendSuper2_stret_debug
	jmp	_objc_msgSendSuper2_stret
	END_ENTRY _objc_msgSendSuper2_stret_debug

	ENTRY _objc_msgSend_fpret_debug
	jmp	_objc_msgSend_fpret
	END_ENTRY _objc_msgSend_fpret_debug

	ENTRY _objc_msgSend_fp2ret_debug
	jmp	_objc_msgSend_fp2ret
	END_ENTRY _objc_msgSend_fp2ret_debug


	ENTRY _objc_msgSend_noarg
	jmp	_objc_msgSend
	END_ENTRY _objc_msgSend_noarg


	ENTRY _method_invoke

	movq	method_imp(%a2), %r11
	movq	method_name(%a2), %a2
	jmp	*%r11
	
	END_ENTRY _method_invoke


	ENTRY _method_invoke_stret

	movq	method_imp(%a3), %r11
	movq	method_name(%a3), %a3
	jmp	*%r11
	
	END_ENTRY _method_invoke_stret


	STATIC_ENTRY __objc_ignored_method

	movq	%a1, %rax
	ret
	
	END_ENTRY __objc_ignored_method
	

.section __DATA,__objc_msg_break
.quad 0
.quad 0

#endif