libgcc/config/mcore/lib1funcs.S

/* libgcc routines for the MCore.
   Copyright (C) 1993-2021 Free Software Foundation, Inc.

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 3, or (at your option) any
later version.

This file is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.

You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
<http://www.gnu.org/licenses/>.  */

#define CONCAT1(a, b) CONCAT2(a, b)
#define CONCAT2(a, b) a ## b

/* Use the right prefix for global labels.  */

#define SYM(x) CONCAT1 (__, x)

#ifdef __ELF__
#define TYPE(x) .type SYM (x),@function
#define SIZE(x) .size SYM (x), . - SYM (x)
#else
#define TYPE(x)
#define SIZE(x)
#endif

.macro FUNC_START name
	.text
	.globl SYM (\name)
	TYPE (\name)
SYM (\name):
.endm

.macro FUNC_END name
	SIZE (\name)
.endm

#ifdef	L_udivsi3
FUNC_START udiv32
FUNC_START udivsi32

	movi	r1,0		// r1-r2 form 64 bit dividend
	movi	r4,1		// r4 is quotient (1 for a sentinel)

	cmpnei	r3,0		// look for 0 divisor
	bt	9f
	trap	3		// divide by 0
9:
	// control iterations; skip across high order 0 bits in dividend
	mov	r7,r2
	cmpnei	r7,0
	bt	8f
	movi	r2,0		// 0 dividend
	jmp	r15		// quick return
8:
	ff1	r7		// figure distance to skip
	lsl	r4,r7		// move the sentinel along (with 0's behind)
	lsl	r2,r7		// and the low 32 bits of numerator

// appears to be wrong...
// tested out incorrectly in our OS work...
//	mov	r7,r3		// looking at divisor
//	ff1	r7		// I can move 32-r7 more bits to left.
//	addi	r7,1		// ok, one short of that...
//	mov	r1,r2
//	lsr	r1,r7		// bits that came from low order...
//	rsubi	r7,31		// r7 == "32-n" == LEFT distance
//	addi	r7,1		// this is (32-n)
//	lsl	r4,r7		// fixes the high 32 (quotient)
//	lsl	r2,r7
//	cmpnei	r4,0
//	bf	4f		// the sentinel went away...

	// run the remaining bits

1:	lslc	r2,1		// 1 bit left shift of r1-r2
	addc	r1,r1
	cmphs	r1,r3		// upper 32 of dividend >= divisor?
	bf	2f
	sub	r1,r3		// if yes, subtract divisor
2:	addc	r4,r4		// shift by 1 and count subtracts
	bf	1b		// if sentinel falls out of quotient, stop

4:	mov	r2,r4		// return quotient
	mov	r3,r1		// and piggyback the remainder
	jmp	r15
FUNC_END udiv32
FUNC_END udivsi32
#endif

#ifdef	L_umodsi3
FUNC_START urem32
FUNC_START umodsi3
	movi	r1,0		// r1-r2 form 64 bit dividend
	movi	r4,1		// r4 is quotient (1 for a sentinel)
	cmpnei	r3,0		// look for 0 divisor
	bt	9f
	trap	3		// divide by 0
9:
	// control iterations; skip across high order 0 bits in dividend
	mov	r7,r2
	cmpnei	r7,0
	bt	8f
	movi	r2,0		// 0 dividend
	jmp	r15		// quick return
8:
	ff1	r7		// figure distance to skip
	lsl	r4,r7		// move the sentinel along (with 0's behind)
	lsl	r2,r7		// and the low 32 bits of numerator

1:	lslc	r2,1		// 1 bit left shift of r1-r2
	addc	r1,r1
	cmphs	r1,r3		// upper 32 of dividend >= divisor?
	bf	2f
	sub	r1,r3		// if yes, subtract divisor
2:	addc	r4,r4		// shift by 1 and count subtracts
	bf	1b		// if sentinel falls out of quotient, stop
	mov	r2,r1		// return remainder
	jmp	r15
FUNC_END urem32
FUNC_END umodsi3
#endif

#ifdef	L_divsi3
FUNC_START div32
FUNC_START divsi3
	mov	r5,r2		// calc sign of quotient
	xor	r5,r3
	abs	r2		// do unsigned divide
	abs	r3
	movi	r1,0		// r1-r2 form 64 bit dividend
	movi	r4,1		// r4 is quotient (1 for a sentinel)
	cmpnei	r3,0		// look for 0 divisor
	bt	9f
	trap	3		// divide by 0
9:
	// control iterations; skip across high order 0 bits in dividend
	mov	r7,r2
	cmpnei	r7,0
	bt	8f
	movi	r2,0		// 0 dividend
	jmp	r15		// quick return
8:
	ff1	r7		// figure distance to skip
	lsl	r4,r7		// move the sentinel along (with 0's behind)
	lsl	r2,r7		// and the low 32 bits of numerator

// tested out incorrectly in our OS work...
//	mov	r7,r3		// looking at divisor
//	ff1	r7		// I can move 32-r7 more bits to left.
//	addi	r7,1		// ok, one short of that...
//	mov	r1,r2
//	lsr	r1,r7		// bits that came from low order...
//	rsubi	r7,31		// r7 == "32-n" == LEFT distance
//	addi	r7,1		// this is (32-n)
//	lsl	r4,r7		// fixes the high 32 (quotient)
//	lsl	r2,r7
//	cmpnei	r4,0
//	bf	4f		// the sentinel went away...

	// run the remaining bits
1:	lslc	r2,1		// 1 bit left shift of r1-r2
	addc	r1,r1
	cmphs	r1,r3		// upper 32 of dividend >= divisor?
	bf	2f
	sub	r1,r3		// if yes, subtract divisor
2:	addc	r4,r4		// shift by 1 and count subtracts
	bf	1b		// if sentinel falls out of quotient, stop

4:	mov	r2,r4		// return quotient
	mov	r3,r1		// piggyback the remainder
	btsti	r5,31		// after adjusting for sign
	bf	3f
	rsubi	r2,0
	rsubi	r3,0
3:	jmp	r15
FUNC_END div32
FUNC_END divsi3
#endif

#ifdef	L_modsi3
FUNC_START rem32
FUNC_START modsi3
	mov	r5,r2		// calc sign of remainder
	abs	r2		// do unsigned divide
	abs	r3
	movi	r1,0		// r1-r2 form 64 bit dividend
	movi	r4,1		// r4 is quotient (1 for a sentinel)
	cmpnei	r3,0		// look for 0 divisor
	bt	9f
	trap	3		// divide by 0
9: 
	// control iterations; skip across high order 0 bits in dividend
	mov	r7,r2
	cmpnei	r7,0
	bt	8f
	movi	r2,0		// 0 dividend
	jmp	r15		// quick return
8:
	ff1	r7		// figure distance to skip
	lsl	r4,r7		// move the sentinel along (with 0's behind)
	lsl	r2,r7		// and the low 32 bits of numerator

1:	lslc	r2,1		// 1 bit left shift of r1-r2
	addc	r1,r1
	cmphs	r1,r3		// upper 32 of dividend >= divisor?
	bf	2f
	sub	r1,r3		// if yes, subtract divisor
2:	addc	r4,r4		// shift by 1 and count subtracts
	bf	1b		// if sentinel falls out of quotient, stop
	mov	r2,r1		// return remainder
	btsti	r5,31		// after adjusting for sign
	bf	3f
	rsubi	r2,0
3:	jmp	r15
FUNC_END rem32
FUNC_END modsi3
#endif


/* GCC expects that {__eq,__ne,__gt,__ge,__le,__lt}{df2,sf2}
   will behave as __cmpdf2. So, we stub the implementations to
   jump on to __cmpdf2 and __cmpsf2.
 
   All of these shortcircuit the return path so that __cmp{sd}f2
   will go directly back to the caller.  */

.macro  COMPARE_DF_JUMP name
	.import SYM (cmpdf2)
FUNC_START \name
	jmpi SYM (cmpdf2)
FUNC_END \name
.endm
		
#ifdef  L_eqdf2
COMPARE_DF_JUMP eqdf2
#endif /* L_eqdf2 */

#ifdef  L_nedf2
COMPARE_DF_JUMP nedf2
#endif /* L_nedf2 */

#ifdef  L_gtdf2
COMPARE_DF_JUMP gtdf2
#endif /* L_gtdf2 */

#ifdef  L_gedf2
COMPARE_DF_JUMP gedf2
#endif /* L_gedf2 */

#ifdef  L_ltdf2
COMPARE_DF_JUMP ltdf2
#endif /* L_ltdf2 */
	
#ifdef  L_ledf2
COMPARE_DF_JUMP ledf2
#endif /* L_ledf2 */

/* SINGLE PRECISION FLOATING POINT STUBS */

.macro  COMPARE_SF_JUMP name
	.import SYM (cmpsf2)
FUNC_START \name
	jmpi SYM (cmpsf2)
FUNC_END \name
.endm
		
#ifdef  L_eqsf2
COMPARE_SF_JUMP eqsf2
#endif /* L_eqsf2 */
	
#ifdef  L_nesf2
COMPARE_SF_JUMP nesf2
#endif /* L_nesf2 */
	
#ifdef  L_gtsf2
COMPARE_SF_JUMP gtsf2
#endif /* L_gtsf2 */
	
#ifdef  L_gesf2
COMPARE_SF_JUMP __gesf2
#endif /* L_gesf2 */
	
#ifdef  L_ltsf2
COMPARE_SF_JUMP __ltsf2
#endif /* L_ltsf2 */
	
#ifdef  L_lesf2
COMPARE_SF_JUMP lesf2
#endif /* L_lesf2 */