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Diffstat (limited to 'contrib/gcc/config/arm/ieee754-df.S')
| -rw-r--r-- | contrib/gcc/config/arm/ieee754-df.S | 1335 |
1 files changed, 0 insertions, 1335 deletions
diff --git a/contrib/gcc/config/arm/ieee754-df.S b/contrib/gcc/config/arm/ieee754-df.S deleted file mode 100644 index 70262a282aa9..000000000000 --- a/contrib/gcc/config/arm/ieee754-df.S +++ /dev/null @@ -1,1335 +0,0 @@ -/* ieee754-df.S double-precision floating point support for ARM - - Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc. - Contributed by Nicolas Pitre (nico@cam.org) - - This file 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 2, or (at your option) any - later version. - - In addition to the permissions in the GNU General Public License, the - Free Software Foundation gives you unlimited permission to link the - compiled version of this file into combinations with other programs, - and to distribute those combinations without any restriction coming - from the use of this file. (The General Public License restrictions - do apply in other respects; for example, they cover modification of - the file, and distribution when not linked into a combine - executable.) - - 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. - - You should have received a copy of the GNU General Public License - along with this program; see the file COPYING. If not, write to - the Free Software Foundation, 51 Franklin Street, Fifth Floor, - Boston, MA 02110-1301, USA. */ - -/* - * Notes: - * - * The goal of this code is to be as fast as possible. This is - * not meant to be easy to understand for the casual reader. - * For slightly simpler code please see the single precision version - * of this file. - * - * Only the default rounding mode is intended for best performances. - * Exceptions aren't supported yet, but that can be added quite easily - * if necessary without impacting performances. - */ - - -@ For FPA, float words are always big-endian. -@ For VFP, floats words follow the memory system mode. -#if (defined(__ARM_EABI__) || defined(__VFP_FP__)) && !defined(__ARMEB__) -#define xl r0 -#define xh r1 -#define yl r2 -#define yh r3 -#else -#define xh r0 -#define xl r1 -#define yh r2 -#define yl r3 -#endif - - -#ifdef L_negdf2 - -ARM_FUNC_START negdf2 -ARM_FUNC_ALIAS aeabi_dneg negdf2 - - @ flip sign bit - eor xh, xh, #0x80000000 - RET - - FUNC_END aeabi_dneg - FUNC_END negdf2 - -#endif - -#ifdef L_addsubdf3 - -ARM_FUNC_START aeabi_drsub - - eor xh, xh, #0x80000000 @ flip sign bit of first arg - b 1f - -ARM_FUNC_START subdf3 -ARM_FUNC_ALIAS aeabi_dsub subdf3 - - eor yh, yh, #0x80000000 @ flip sign bit of second arg -#if defined(__INTERWORKING_STUBS__) - b 1f @ Skip Thumb-code prologue -#endif - -ARM_FUNC_START adddf3 -ARM_FUNC_ALIAS aeabi_dadd adddf3 - -1: stmfd sp!, {r4, r5, lr} - - @ Look for zeroes, equal values, INF, or NAN. - mov r4, xh, lsl #1 - mov r5, yh, lsl #1 - teq r4, r5 - teqeq xl, yl - orrnes ip, r4, xl - orrnes ip, r5, yl - mvnnes ip, r4, asr #21 - mvnnes ip, r5, asr #21 - beq LSYM(Lad_s) - - @ Compute exponent difference. Make largest exponent in r4, - @ corresponding arg in xh-xl, and positive exponent difference in r5. - mov r4, r4, lsr #21 - rsbs r5, r4, r5, lsr #21 - rsblt r5, r5, #0 - ble 1f - add r4, r4, r5 - eor yl, xl, yl - eor yh, xh, yh - eor xl, yl, xl - eor xh, yh, xh - eor yl, xl, yl - eor yh, xh, yh -1: - @ If exponent difference is too large, return largest argument - @ already in xh-xl. We need up to 54 bit to handle proper rounding - @ of 0x1p54 - 1.1. - cmp r5, #54 - RETLDM "r4, r5" hi - - @ Convert mantissa to signed integer. - tst xh, #0x80000000 - mov xh, xh, lsl #12 - mov ip, #0x00100000 - orr xh, ip, xh, lsr #12 - beq 1f - rsbs xl, xl, #0 - rsc xh, xh, #0 -1: - tst yh, #0x80000000 - mov yh, yh, lsl #12 - orr yh, ip, yh, lsr #12 - beq 1f - rsbs yl, yl, #0 - rsc yh, yh, #0 -1: - @ If exponent == difference, one or both args were denormalized. - @ Since this is not common case, rescale them off line. - teq r4, r5 - beq LSYM(Lad_d) -LSYM(Lad_x): - - @ Compensate for the exponent overlapping the mantissa MSB added later - sub r4, r4, #1 - - @ Shift yh-yl right per r5, add to xh-xl, keep leftover bits into ip. - rsbs lr, r5, #32 - blt 1f - mov ip, yl, lsl lr - adds xl, xl, yl, lsr r5 - adc xh, xh, #0 - adds xl, xl, yh, lsl lr - adcs xh, xh, yh, asr r5 - b 2f -1: sub r5, r5, #32 - add lr, lr, #32 - cmp yl, #1 - mov ip, yh, lsl lr - orrcs ip, ip, #2 @ 2 not 1, to allow lsr #1 later - adds xl, xl, yh, asr r5 - adcs xh, xh, yh, asr #31 -2: - @ We now have a result in xh-xl-ip. - @ Keep absolute value in xh-xl-ip, sign in r5 (the n bit was set above) - and r5, xh, #0x80000000 - bpl LSYM(Lad_p) - rsbs ip, ip, #0 - rscs xl, xl, #0 - rsc xh, xh, #0 - - @ Determine how to normalize the result. -LSYM(Lad_p): - cmp xh, #0x00100000 - bcc LSYM(Lad_a) - cmp xh, #0x00200000 - bcc LSYM(Lad_e) - - @ Result needs to be shifted right. - movs xh, xh, lsr #1 - movs xl, xl, rrx - mov ip, ip, rrx - add r4, r4, #1 - - @ Make sure we did not bust our exponent. - mov r2, r4, lsl #21 - cmn r2, #(2 << 21) - bcs LSYM(Lad_o) - - @ Our result is now properly aligned into xh-xl, remaining bits in ip. - @ Round with MSB of ip. If halfway between two numbers, round towards - @ LSB of xl = 0. - @ Pack final result together. -LSYM(Lad_e): - cmp ip, #0x80000000 - moveqs ip, xl, lsr #1 - adcs xl, xl, #0 - adc xh, xh, r4, lsl #20 - orr xh, xh, r5 - RETLDM "r4, r5" - - @ Result must be shifted left and exponent adjusted. -LSYM(Lad_a): - movs ip, ip, lsl #1 - adcs xl, xl, xl - adc xh, xh, xh - tst xh, #0x00100000 - sub r4, r4, #1 - bne LSYM(Lad_e) - - @ No rounding necessary since ip will always be 0 at this point. -LSYM(Lad_l): - -#if __ARM_ARCH__ < 5 - - teq xh, #0 - movne r3, #20 - moveq r3, #52 - moveq xh, xl - moveq xl, #0 - mov r2, xh - cmp r2, #(1 << 16) - movhs r2, r2, lsr #16 - subhs r3, r3, #16 - cmp r2, #(1 << 8) - movhs r2, r2, lsr #8 - subhs r3, r3, #8 - cmp r2, #(1 << 4) - movhs r2, r2, lsr #4 - subhs r3, r3, #4 - cmp r2, #(1 << 2) - subhs r3, r3, #2 - sublo r3, r3, r2, lsr #1 - sub r3, r3, r2, lsr #3 - -#else - - teq xh, #0 - moveq xh, xl - moveq xl, #0 - clz r3, xh - addeq r3, r3, #32 - sub r3, r3, #11 - -#endif - - @ determine how to shift the value. - subs r2, r3, #32 - bge 2f - adds r2, r2, #12 - ble 1f - - @ shift value left 21 to 31 bits, or actually right 11 to 1 bits - @ since a register switch happened above. - add ip, r2, #20 - rsb r2, r2, #12 - mov xl, xh, lsl ip - mov xh, xh, lsr r2 - b 3f - - @ actually shift value left 1 to 20 bits, which might also represent - @ 32 to 52 bits if counting the register switch that happened earlier. -1: add r2, r2, #20 -2: rsble ip, r2, #32 - mov xh, xh, lsl r2 - orrle xh, xh, xl, lsr ip - movle xl, xl, lsl r2 - - @ adjust exponent accordingly. -3: subs r4, r4, r3 - addge xh, xh, r4, lsl #20 - orrge xh, xh, r5 - RETLDM "r4, r5" ge - - @ Exponent too small, denormalize result. - @ Find out proper shift value. - mvn r4, r4 - subs r4, r4, #31 - bge 2f - adds r4, r4, #12 - bgt 1f - - @ shift result right of 1 to 20 bits, sign is in r5. - add r4, r4, #20 - rsb r2, r4, #32 - mov xl, xl, lsr r4 - orr xl, xl, xh, lsl r2 - orr xh, r5, xh, lsr r4 - RETLDM "r4, r5" - - @ shift result right of 21 to 31 bits, or left 11 to 1 bits after - @ a register switch from xh to xl. -1: rsb r4, r4, #12 - rsb r2, r4, #32 - mov xl, xl, lsr r2 - orr xl, xl, xh, lsl r4 - mov xh, r5 - RETLDM "r4, r5" - - @ Shift value right of 32 to 64 bits, or 0 to 32 bits after a switch - @ from xh to xl. -2: mov xl, xh, lsr r4 - mov xh, r5 - RETLDM "r4, r5" - - @ Adjust exponents for denormalized arguments. - @ Note that r4 must not remain equal to 0. -LSYM(Lad_d): - teq r4, #0 - eor yh, yh, #0x00100000 - eoreq xh, xh, #0x00100000 - addeq r4, r4, #1 - subne r5, r5, #1 - b LSYM(Lad_x) - - -LSYM(Lad_s): - mvns ip, r4, asr #21 - mvnnes ip, r5, asr #21 - beq LSYM(Lad_i) - - teq r4, r5 - teqeq xl, yl - beq 1f - - @ Result is x + 0.0 = x or 0.0 + y = y. - orrs ip, r4, xl - moveq xh, yh - moveq xl, yl - RETLDM "r4, r5" - -1: teq xh, yh - - @ Result is x - x = 0. - movne xh, #0 - movne xl, #0 - RETLDM "r4, r5" ne - - @ Result is x + x = 2x. - movs ip, r4, lsr #21 - bne 2f - movs xl, xl, lsl #1 - adcs xh, xh, xh - orrcs xh, xh, #0x80000000 - RETLDM "r4, r5" -2: adds r4, r4, #(2 << 21) - addcc xh, xh, #(1 << 20) - RETLDM "r4, r5" cc - and r5, xh, #0x80000000 - - @ Overflow: return INF. -LSYM(Lad_o): - orr xh, r5, #0x7f000000 - orr xh, xh, #0x00f00000 - mov xl, #0 - RETLDM "r4, r5" - - @ At least one of x or y is INF/NAN. - @ if xh-xl != INF/NAN: return yh-yl (which is INF/NAN) - @ if yh-yl != INF/NAN: return xh-xl (which is INF/NAN) - @ if either is NAN: return NAN - @ if opposite sign: return NAN - @ otherwise return xh-xl (which is INF or -INF) -LSYM(Lad_i): - mvns ip, r4, asr #21 - movne xh, yh - movne xl, yl - mvneqs ip, r5, asr #21 - movne yh, xh - movne yl, xl - orrs r4, xl, xh, lsl #12 - orreqs r5, yl, yh, lsl #12 - teqeq xh, yh - orrne xh, xh, #0x00080000 @ quiet NAN - RETLDM "r4, r5" - - FUNC_END aeabi_dsub - FUNC_END subdf3 - FUNC_END aeabi_dadd - FUNC_END adddf3 - -ARM_FUNC_START floatunsidf -ARM_FUNC_ALIAS aeabi_ui2d floatunsidf - - teq r0, #0 - moveq r1, #0 - RETc(eq) - stmfd sp!, {r4, r5, lr} - mov r4, #0x400 @ initial exponent - add r4, r4, #(52-1 - 1) - mov r5, #0 @ sign bit is 0 - .ifnc xl, r0 - mov xl, r0 - .endif - mov xh, #0 - b LSYM(Lad_l) - - FUNC_END aeabi_ui2d - FUNC_END floatunsidf - -ARM_FUNC_START floatsidf -ARM_FUNC_ALIAS aeabi_i2d floatsidf - - teq r0, #0 - moveq r1, #0 - RETc(eq) - stmfd sp!, {r4, r5, lr} - mov r4, #0x400 @ initial exponent - add r4, r4, #(52-1 - 1) - ands r5, r0, #0x80000000 @ sign bit in r5 - rsbmi r0, r0, #0 @ absolute value - .ifnc xl, r0 - mov xl, r0 - .endif - mov xh, #0 - b LSYM(Lad_l) - - FUNC_END aeabi_i2d - FUNC_END floatsidf - -ARM_FUNC_START extendsfdf2 -ARM_FUNC_ALIAS aeabi_f2d extendsfdf2 - - movs r2, r0, lsl #1 @ toss sign bit - mov xh, r2, asr #3 @ stretch exponent - mov xh, xh, rrx @ retrieve sign bit - mov xl, r2, lsl #28 @ retrieve remaining bits - andnes r3, r2, #0xff000000 @ isolate exponent - teqne r3, #0xff000000 @ if not 0, check if INF or NAN - eorne xh, xh, #0x38000000 @ fixup exponent otherwise. - RETc(ne) @ and return it. - - teq r2, #0 @ if actually 0 - teqne r3, #0xff000000 @ or INF or NAN - RETc(eq) @ we are done already. - - @ value was denormalized. We can normalize it now. - stmfd sp!, {r4, r5, lr} - mov r4, #0x380 @ setup corresponding exponent - and r5, xh, #0x80000000 @ move sign bit in r5 - bic xh, xh, #0x80000000 - b LSYM(Lad_l) - - FUNC_END aeabi_f2d - FUNC_END extendsfdf2 - -ARM_FUNC_START floatundidf -ARM_FUNC_ALIAS aeabi_ul2d floatundidf - - orrs r2, r0, r1 -#if !defined (__VFP_FP__) && !defined(__SOFTFP__) - mvfeqd f0, #0.0 -#endif - RETc(eq) - -#if !defined (__VFP_FP__) && !defined(__SOFTFP__) - @ For hard FPA code we want to return via the tail below so that - @ we can return the result in f0 as well as in r0/r1 for backwards - @ compatibility. - adr ip, LSYM(f0_ret) - stmfd sp!, {r4, r5, ip, lr} -#else - stmfd sp!, {r4, r5, lr} -#endif - - mov r5, #0 - b 2f - -ARM_FUNC_START floatdidf -ARM_FUNC_ALIAS aeabi_l2d floatdidf - - orrs r2, r0, r1 -#if !defined (__VFP_FP__) && !defined(__SOFTFP__) - mvfeqd f0, #0.0 -#endif - RETc(eq) - -#if !defined (__VFP_FP__) && !defined(__SOFTFP__) - @ For hard FPA code we want to return via the tail below so that - @ we can return the result in f0 as well as in r0/r1 for backwards - @ compatibility. - adr ip, LSYM(f0_ret) - stmfd sp!, {r4, r5, ip, lr} -#else - stmfd sp!, {r4, r5, lr} -#endif - - ands r5, ah, #0x80000000 @ sign bit in r5 - bpl 2f - rsbs al, al, #0 - rsc ah, ah, #0 -2: - mov r4, #0x400 @ initial exponent - add r4, r4, #(52-1 - 1) - - @ FPA little-endian: must swap the word order. - .ifnc xh, ah - mov ip, al - mov xh, ah - mov xl, ip - .endif - - movs ip, xh, lsr #22 - beq LSYM(Lad_p) - - @ The value is too big. Scale it down a bit... - mov r2, #3 - movs ip, ip, lsr #3 - addne r2, r2, #3 - movs ip, ip, lsr #3 - addne r2, r2, #3 - add r2, r2, ip, lsr #3 - - rsb r3, r2, #32 - mov ip, xl, lsl r3 - mov xl, xl, lsr r2 - orr xl, xl, xh, lsl r3 - mov xh, xh, lsr r2 - add r4, r4, r2 - b LSYM(Lad_p) - -#if !defined (__VFP_FP__) && !defined(__SOFTFP__) - - @ Legacy code expects the result to be returned in f0. Copy it - @ there as well. -LSYM(f0_ret): - stmfd sp!, {r0, r1} - ldfd f0, [sp], #8 - RETLDM - -#endif - - FUNC_END floatdidf - FUNC_END aeabi_l2d - FUNC_END floatundidf - FUNC_END aeabi_ul2d - -#endif /* L_addsubdf3 */ - -#ifdef L_muldivdf3 - -ARM_FUNC_START muldf3 -ARM_FUNC_ALIAS aeabi_dmul muldf3 - stmfd sp!, {r4, r5, r6, lr} - - @ Mask out exponents, trap any zero/denormal/INF/NAN. - mov ip, #0xff - orr ip, ip, #0x700 - ands r4, ip, xh, lsr #20 - andnes r5, ip, yh, lsr #20 - teqne r4, ip - teqne r5, ip - bleq LSYM(Lml_s) - - @ Add exponents together - add r4, r4, r5 - - @ Determine final sign. - eor r6, xh, yh - - @ Convert mantissa to unsigned integer. - @ If power of two, branch to a separate path. - bic xh, xh, ip, lsl #21 - bic yh, yh, ip, lsl #21 - orrs r5, xl, xh, lsl #12 - orrnes r5, yl, yh, lsl #12 - orr xh, xh, #0x00100000 - orr yh, yh, #0x00100000 - beq LSYM(Lml_1) - -#if __ARM_ARCH__ < 4 - - @ Put sign bit in r6, which will be restored in yl later. - and r6, r6, #0x80000000 - - @ Well, no way to make it shorter without the umull instruction. - stmfd sp!, {r6, r7, r8, r9, sl, fp} - mov r7, xl, lsr #16 - mov r8, yl, lsr #16 - mov r9, xh, lsr #16 - mov sl, yh, lsr #16 - bic xl, xl, r7, lsl #16 - bic yl, yl, r8, lsl #16 - bic xh, xh, r9, lsl #16 - bic yh, yh, sl, lsl #16 - mul ip, xl, yl - mul fp, xl, r8 - mov lr, #0 - adds ip, ip, fp, lsl #16 - adc lr, lr, fp, lsr #16 - mul fp, r7, yl - adds ip, ip, fp, lsl #16 - adc lr, lr, fp, lsr #16 - mul fp, xl, sl - mov r5, #0 - adds lr, lr, fp, lsl #16 - adc r5, r5, fp, lsr #16 - mul fp, r7, yh - adds lr, lr, fp, lsl #16 - adc r5, r5, fp, lsr #16 - mul fp, xh, r8 - adds lr, lr, fp, lsl #16 - adc r5, r5, fp, lsr #16 - mul fp, r9, yl - adds lr, lr, fp, lsl #16 - adc r5, r5, fp, lsr #16 - mul fp, xh, sl - mul r6, r9, sl - adds r5, r5, fp, lsl #16 - adc r6, r6, fp, lsr #16 - mul fp, r9, yh - adds r5, r5, fp, lsl #16 - adc r6, r6, fp, lsr #16 - mul fp, xl, yh - adds lr, lr, fp - mul fp, r7, sl - adcs r5, r5, fp - mul fp, xh, yl - adc r6, r6, #0 - adds lr, lr, fp - mul fp, r9, r8 - adcs r5, r5, fp - mul fp, r7, r8 - adc r6, r6, #0 - adds lr, lr, fp - mul fp, xh, yh - adcs r5, r5, fp - adc r6, r6, #0 - ldmfd sp!, {yl, r7, r8, r9, sl, fp} - -#else - - @ Here is the actual multiplication. - umull ip, lr, xl, yl - mov r5, #0 - umlal lr, r5, xh, yl - and yl, r6, #0x80000000 - umlal lr, r5, xl, yh - mov r6, #0 - umlal r5, r6, xh, yh - -#endif - - @ The LSBs in ip are only significant for the final rounding. - @ Fold them into lr. - teq ip, #0 - orrne lr, lr, #1 - - @ Adjust result upon the MSB position. - sub r4, r4, #0xff - cmp r6, #(1 << (20-11)) - sbc r4, r4, #0x300 - bcs 1f - movs lr, lr, lsl #1 - adcs r5, r5, r5 - adc r6, r6, r6 -1: - @ Shift to final position, add sign to result. - orr xh, yl, r6, lsl #11 - orr xh, xh, r5, lsr #21 - mov xl, r5, lsl #11 - orr xl, xl, lr, lsr #21 - mov lr, lr, lsl #11 - - @ Check exponent range for under/overflow. - subs ip, r4, #(254 - 1) - cmphi ip, #0x700 - bhi LSYM(Lml_u) - - @ Round the result, merge final exponent. - cmp lr, #0x80000000 - moveqs lr, xl, lsr #1 - adcs xl, xl, #0 - adc xh, xh, r4, lsl #20 - RETLDM "r4, r5, r6" - - @ Multiplication by 0x1p*: let''s shortcut a lot of code. -LSYM(Lml_1): - and r6, r6, #0x80000000 - orr xh, r6, xh - orr xl, xl, yl - eor xh, xh, yh - subs r4, r4, ip, lsr #1 - rsbgts r5, r4, ip - orrgt xh, xh, r4, lsl #20 - RETLDM "r4, r5, r6" gt - - @ Under/overflow: fix things up for the code below. - orr xh, xh, #0x00100000 - mov lr, #0 - subs r4, r4, #1 - -LSYM(Lml_u): - @ Overflow? - bgt LSYM(Lml_o) - - @ Check if denormalized result is possible, otherwise return signed 0. - cmn r4, #(53 + 1) - movle xl, #0 - bicle xh, xh, #0x7fffffff - RETLDM "r4, r5, r6" le - - @ Find out proper shift value. - rsb r4, r4, #0 - subs r4, r4, #32 - bge 2f - adds r4, r4, #12 - bgt 1f - - @ shift result right of 1 to 20 bits, preserve sign bit, round, etc. - add r4, r4, #20 - rsb r5, r4, #32 - mov r3, xl, lsl r5 - mov xl, xl, lsr r4 - orr xl, xl, xh, lsl r5 - and r2, xh, #0x80000000 - bic xh, xh, #0x80000000 - adds xl, xl, r3, lsr #31 - adc xh, r2, xh, lsr r4 - orrs lr, lr, r3, lsl #1 - biceq xl, xl, r3, lsr #31 - RETLDM "r4, r5, r6" - - @ shift result right of 21 to 31 bits, or left 11 to 1 bits after - @ a register switch from xh to xl. Then round. -1: rsb r4, r4, #12 - rsb r5, r4, #32 - mov r3, xl, lsl r4 - mov xl, xl, lsr r5 - orr xl, xl, xh, lsl r4 - bic xh, xh, #0x7fffffff - adds xl, xl, r3, lsr #31 - adc xh, xh, #0 - orrs lr, lr, r3, lsl #1 - biceq xl, xl, r3, lsr #31 - RETLDM "r4, r5, r6" - - @ Shift value right of 32 to 64 bits, or 0 to 32 bits after a switch - @ from xh to xl. Leftover bits are in r3-r6-lr for rounding. -2: rsb r5, r4, #32 - orr lr, lr, xl, lsl r5 - mov r3, xl, lsr r4 - orr r3, r3, xh, lsl r5 - mov xl, xh, lsr r4 - bic xh, xh, #0x7fffffff - bic xl, xl, xh, lsr r4 - add xl, xl, r3, lsr #31 - orrs lr, lr, r3, lsl #1 - biceq xl, xl, r3, lsr #31 - RETLDM "r4, r5, r6" - - @ One or both arguments are denormalized. - @ Scale them leftwards and preserve sign bit. -LSYM(Lml_d): - teq r4, #0 - bne 2f - and r6, xh, #0x80000000 -1: movs xl, xl, lsl #1 - adc xh, xh, xh - tst xh, #0x00100000 - subeq r4, r4, #1 - beq 1b - orr xh, xh, r6 - teq r5, #0 - movne pc, lr -2: and r6, yh, #0x80000000 -3: movs yl, yl, lsl #1 - adc yh, yh, yh - tst yh, #0x00100000 - subeq r5, r5, #1 - beq 3b - orr yh, yh, r6 - mov pc, lr - -LSYM(Lml_s): - @ Isolate the INF and NAN cases away - teq r4, ip - and r5, ip, yh, lsr #20 - teqne r5, ip - beq 1f - - @ Here, one or more arguments are either denormalized or zero. - orrs r6, xl, xh, lsl #1 - orrnes r6, yl, yh, lsl #1 - bne LSYM(Lml_d) - - @ Result is 0, but determine sign anyway. -LSYM(Lml_z): - eor xh, xh, yh - bic xh, xh, #0x7fffffff - mov xl, #0 - RETLDM "r4, r5, r6" - -1: @ One or both args are INF or NAN. - orrs r6, xl, xh, lsl #1 - moveq xl, yl - moveq xh, yh - orrnes r6, yl, yh, lsl #1 - beq LSYM(Lml_n) @ 0 * INF or INF * 0 -> NAN - teq r4, ip - bne 1f - orrs r6, xl, xh, lsl #12 - bne LSYM(Lml_n) @ NAN * <anything> -> NAN -1: teq r5, ip - bne LSYM(Lml_i) - orrs r6, yl, yh, lsl #12 - movne xl, yl - movne xh, yh - bne LSYM(Lml_n) @ <anything> * NAN -> NAN - - @ Result is INF, but we need to determine its sign. -LSYM(Lml_i): - eor xh, xh, yh - - @ Overflow: return INF (sign already in xh). -LSYM(Lml_o): - and xh, xh, #0x80000000 - orr xh, xh, #0x7f000000 - orr xh, xh, #0x00f00000 - mov xl, #0 - RETLDM "r4, r5, r6" - - @ Return a quiet NAN. -LSYM(Lml_n): - orr xh, xh, #0x7f000000 - orr xh, xh, #0x00f80000 - RETLDM "r4, r5, r6" - - FUNC_END aeabi_dmul - FUNC_END muldf3 - -ARM_FUNC_START divdf3 -ARM_FUNC_ALIAS aeabi_ddiv divdf3 - - stmfd sp!, {r4, r5, r6, lr} - - @ Mask out exponents, trap any zero/denormal/INF/NAN. - mov ip, #0xff - orr ip, ip, #0x700 - ands r4, ip, xh, lsr #20 - andnes r5, ip, yh, lsr #20 - teqne r4, ip - teqne r5, ip - bleq LSYM(Ldv_s) - - @ Substract divisor exponent from dividend''s. - sub r4, r4, r5 - - @ Preserve final sign into lr. - eor lr, xh, yh - - @ Convert mantissa to unsigned integer. - @ Dividend -> r5-r6, divisor -> yh-yl. - orrs r5, yl, yh, lsl #12 - mov xh, xh, lsl #12 - beq LSYM(Ldv_1) - mov yh, yh, lsl #12 - mov r5, #0x10000000 - orr yh, r5, yh, lsr #4 - orr yh, yh, yl, lsr #24 - mov yl, yl, lsl #8 - orr r5, r5, xh, lsr #4 - orr r5, r5, xl, lsr #24 - mov r6, xl, lsl #8 - - @ Initialize xh with final sign bit. - and xh, lr, #0x80000000 - - @ Ensure result will land to known bit position. - @ Apply exponent bias accordingly. - cmp r5, yh - cmpeq r6, yl - adc r4, r4, #(255 - 2) - add r4, r4, #0x300 - bcs 1f - movs yh, yh, lsr #1 - mov yl, yl, rrx -1: - @ Perform first substraction to align result to a nibble. - subs r6, r6, yl - sbc r5, r5, yh - movs yh, yh, lsr #1 - mov yl, yl, rrx - mov xl, #0x00100000 - mov ip, #0x00080000 - - @ The actual division loop. -1: subs lr, r6, yl - sbcs lr, r5, yh - subcs r6, r6, yl - movcs r5, lr - orrcs xl, xl, ip - movs yh, yh, lsr #1 - mov yl, yl, rrx - subs lr, r6, yl - sbcs lr, r5, yh - subcs r6, r6, yl - movcs r5, lr - orrcs xl, xl, ip, lsr #1 - movs yh, yh, lsr #1 - mov yl, yl, rrx - subs lr, r6, yl - sbcs lr, r5, yh - subcs r6, r6, yl - movcs r5, lr - orrcs xl, xl, ip, lsr #2 - movs yh, yh, lsr #1 - mov yl, yl, rrx - subs lr, r6, yl - sbcs lr, r5, yh - subcs r6, r6, yl - movcs r5, lr - orrcs xl, xl, ip, lsr #3 - - orrs lr, r5, r6 - beq 2f - mov r5, r5, lsl #4 - orr r5, r5, r6, lsr #28 - mov r6, r6, lsl #4 - mov yh, yh, lsl #3 - orr yh, yh, yl, lsr #29 - mov yl, yl, lsl #3 - movs ip, ip, lsr #4 - bne 1b - - @ We are done with a word of the result. - @ Loop again for the low word if this pass was for the high word. - tst xh, #0x00100000 - bne 3f - orr xh, xh, xl - mov xl, #0 - mov ip, #0x80000000 - b 1b -2: - @ Be sure result starts in the high word. - tst xh, #0x00100000 - orreq xh, xh, xl - moveq xl, #0 -3: - @ Check exponent range for under/overflow. - subs ip, r4, #(254 - 1) - cmphi ip, #0x700 - bhi LSYM(Lml_u) - - @ Round the result, merge final exponent. - subs ip, r5, yh - subeqs ip, r6, yl - moveqs ip, xl, lsr #1 - adcs xl, xl, #0 - adc xh, xh, r4, lsl #20 - RETLDM "r4, r5, r6" - - @ Division by 0x1p*: shortcut a lot of code. -LSYM(Ldv_1): - and lr, lr, #0x80000000 - orr xh, lr, xh, lsr #12 - adds r4, r4, ip, lsr #1 - rsbgts r5, r4, ip - orrgt xh, xh, r4, lsl #20 - RETLDM "r4, r5, r6" gt - - orr xh, xh, #0x00100000 - mov lr, #0 - subs r4, r4, #1 - b LSYM(Lml_u) - - @ Result mightt need to be denormalized: put remainder bits - @ in lr for rounding considerations. -LSYM(Ldv_u): - orr lr, r5, r6 - b LSYM(Lml_u) - - @ One or both arguments is either INF, NAN or zero. -LSYM(Ldv_s): - and r5, ip, yh, lsr #20 - teq r4, ip - teqeq r5, ip - beq LSYM(Lml_n) @ INF/NAN / INF/NAN -> NAN - teq r4, ip - bne 1f - orrs r4, xl, xh, lsl #12 - bne LSYM(Lml_n) @ NAN / <anything> -> NAN - teq r5, ip - bne LSYM(Lml_i) @ INF / <anything> -> INF - mov xl, yl - mov xh, yh - b LSYM(Lml_n) @ INF / (INF or NAN) -> NAN -1: teq r5, ip - bne 2f - orrs r5, yl, yh, lsl #12 - beq LSYM(Lml_z) @ <anything> / INF -> 0 - mov xl, yl - mov xh, yh - b LSYM(Lml_n) @ <anything> / NAN -> NAN -2: @ If both are nonzero, we need to normalize and resume above. - orrs r6, xl, xh, lsl #1 - orrnes r6, yl, yh, lsl #1 - bne LSYM(Lml_d) - @ One or both arguments are 0. - orrs r4, xl, xh, lsl #1 - bne LSYM(Lml_i) @ <non_zero> / 0 -> INF - orrs r5, yl, yh, lsl #1 - bne LSYM(Lml_z) @ 0 / <non_zero> -> 0 - b LSYM(Lml_n) @ 0 / 0 -> NAN - - FUNC_END aeabi_ddiv - FUNC_END divdf3 - -#endif /* L_muldivdf3 */ - -#ifdef L_cmpdf2 - -@ Note: only r0 (return value) and ip are clobbered here. - -ARM_FUNC_START gtdf2 -ARM_FUNC_ALIAS gedf2 gtdf2 - mov ip, #-1 - b 1f - -ARM_FUNC_START ltdf2 -ARM_FUNC_ALIAS ledf2 ltdf2 - mov ip, #1 - b 1f - -ARM_FUNC_START cmpdf2 -ARM_FUNC_ALIAS nedf2 cmpdf2 -ARM_FUNC_ALIAS eqdf2 cmpdf2 - mov ip, #1 @ how should we specify unordered here? - -1: str ip, [sp, #-4] - - @ Trap any INF/NAN first. - mov ip, xh, lsl #1 - mvns ip, ip, asr #21 - mov ip, yh, lsl #1 - mvnnes ip, ip, asr #21 - beq 3f - - @ Test for equality. - @ Note that 0.0 is equal to -0.0. -2: orrs ip, xl, xh, lsl #1 @ if x == 0.0 or -0.0 - orreqs ip, yl, yh, lsl #1 @ and y == 0.0 or -0.0 - teqne xh, yh @ or xh == yh - teqeq xl, yl @ and xl == yl - moveq r0, #0 @ then equal. - RETc(eq) - - @ Clear C flag - cmn r0, #0 - - @ Compare sign, - teq xh, yh - - @ Compare values if same sign - cmppl xh, yh - cmpeq xl, yl - - @ Result: - movcs r0, yh, asr #31 - mvncc r0, yh, asr #31 - orr r0, r0, #1 - RET - - @ Look for a NAN. -3: mov ip, xh, lsl #1 - mvns ip, ip, asr #21 - bne 4f - orrs ip, xl, xh, lsl #12 - bne 5f @ x is NAN -4: mov ip, yh, lsl #1 - mvns ip, ip, asr #21 - bne 2b - orrs ip, yl, yh, lsl #12 - beq 2b @ y is not NAN -5: ldr r0, [sp, #-4] @ unordered return code - RET - - FUNC_END gedf2 - FUNC_END gtdf2 - FUNC_END ledf2 - FUNC_END ltdf2 - FUNC_END nedf2 - FUNC_END eqdf2 - FUNC_END cmpdf2 - -ARM_FUNC_START aeabi_cdrcmple - - mov ip, r0 - mov r0, r2 - mov r2, ip - mov ip, r1 - mov r1, r3 - mov r3, ip - b 6f - -ARM_FUNC_START aeabi_cdcmpeq -ARM_FUNC_ALIAS aeabi_cdcmple aeabi_cdcmpeq - - @ The status-returning routines are required to preserve all - @ registers except ip, lr, and cpsr. -6: stmfd sp!, {r0, lr} - ARM_CALL cmpdf2 - @ Set the Z flag correctly, and the C flag unconditionally. - cmp r0, #0 - @ Clear the C flag if the return value was -1, indicating - @ that the first operand was smaller than the second. - cmnmi r0, #0 - RETLDM "r0" - - FUNC_END aeabi_cdcmple - FUNC_END aeabi_cdcmpeq - FUNC_END aeabi_cdrcmple - -ARM_FUNC_START aeabi_dcmpeq - - str lr, [sp, #-8]! - ARM_CALL aeabi_cdcmple - moveq r0, #1 @ Equal to. - movne r0, #0 @ Less than, greater than, or unordered. - RETLDM - - FUNC_END aeabi_dcmpeq - -ARM_FUNC_START aeabi_dcmplt - - str lr, [sp, #-8]! - ARM_CALL aeabi_cdcmple - movcc r0, #1 @ Less than. - movcs r0, #0 @ Equal to, greater than, or unordered. - RETLDM - - FUNC_END aeabi_dcmplt - -ARM_FUNC_START aeabi_dcmple - - str lr, [sp, #-8]! - ARM_CALL aeabi_cdcmple - movls r0, #1 @ Less than or equal to. - movhi r0, #0 @ Greater than or unordered. - RETLDM - - FUNC_END aeabi_dcmple - -ARM_FUNC_START aeabi_dcmpge - - str lr, [sp, #-8]! - ARM_CALL aeabi_cdrcmple - movls r0, #1 @ Operand 2 is less than or equal to operand 1. - movhi r0, #0 @ Operand 2 greater than operand 1, or unordered. - RETLDM - - FUNC_END aeabi_dcmpge - -ARM_FUNC_START aeabi_dcmpgt - - str lr, [sp, #-8]! - ARM_CALL aeabi_cdrcmple - movcc r0, #1 @ Operand 2 is less than operand 1. - movcs r0, #0 @ Operand 2 is greater than or equal to operand 1, - @ or they are unordered. - RETLDM - - FUNC_END aeabi_dcmpgt - -#endif /* L_cmpdf2 */ - -#ifdef L_unorddf2 - -ARM_FUNC_START unorddf2 -ARM_FUNC_ALIAS aeabi_dcmpun unorddf2 - - mov ip, xh, lsl #1 - mvns ip, ip, asr #21 - bne 1f - orrs ip, xl, xh, lsl #12 - bne 3f @ x is NAN -1: mov ip, yh, lsl #1 - mvns ip, ip, asr #21 - bne 2f - orrs ip, yl, yh, lsl #12 - bne 3f @ y is NAN -2: mov r0, #0 @ arguments are ordered. - RET - -3: mov r0, #1 @ arguments are unordered. - RET - - FUNC_END aeabi_dcmpun - FUNC_END unorddf2 - -#endif /* L_unorddf2 */ - -#ifdef L_fixdfsi - -ARM_FUNC_START fixdfsi -ARM_FUNC_ALIAS aeabi_d2iz fixdfsi - - @ check exponent range. - mov r2, xh, lsl #1 - adds r2, r2, #(1 << 21) - bcs 2f @ value is INF or NAN - bpl 1f @ value is too small - mov r3, #(0xfffffc00 + 31) - subs r2, r3, r2, asr #21 - bls 3f @ value is too large - - @ scale value - mov r3, xh, lsl #11 - orr r3, r3, #0x80000000 - orr r3, r3, xl, lsr #21 - tst xh, #0x80000000 @ the sign bit - mov r0, r3, lsr r2 - rsbne r0, r0, #0 - RET - -1: mov r0, #0 - RET - -2: orrs xl, xl, xh, lsl #12 - bne 4f @ x is NAN. -3: ands r0, xh, #0x80000000 @ the sign bit - moveq r0, #0x7fffffff @ maximum signed positive si - RET - -4: mov r0, #0 @ How should we convert NAN? - RET - - FUNC_END aeabi_d2iz - FUNC_END fixdfsi - -#endif /* L_fixdfsi */ - -#ifdef L_fixunsdfsi - -ARM_FUNC_START fixunsdfsi -ARM_FUNC_ALIAS aeabi_d2uiz fixunsdfsi - - @ check exponent range. - movs r2, xh, lsl #1 - bcs 1f @ value is negative - adds r2, r2, #(1 << 21) - bcs 2f @ value is INF or NAN - bpl 1f @ value is too small - mov r3, #(0xfffffc00 + 31) - subs r2, r3, r2, asr #21 - bmi 3f @ value is too large - - @ scale value - mov r3, xh, lsl #11 - orr r3, r3, #0x80000000 - orr r3, r3, xl, lsr #21 - mov r0, r3, lsr r2 - RET - -1: mov r0, #0 - RET - -2: orrs xl, xl, xh, lsl #12 - bne 4f @ value is NAN. -3: mov r0, #0xffffffff @ maximum unsigned si - RET - -4: mov r0, #0 @ How should we convert NAN? - RET - - FUNC_END aeabi_d2uiz - FUNC_END fixunsdfsi - -#endif /* L_fixunsdfsi */ - -#ifdef L_truncdfsf2 - -ARM_FUNC_START truncdfsf2 -ARM_FUNC_ALIAS aeabi_d2f truncdfsf2 - - @ check exponent range. - mov r2, xh, lsl #1 - subs r3, r2, #((1023 - 127) << 21) - subcss ip, r3, #(1 << 21) - rsbcss ip, ip, #(254 << 21) - bls 2f @ value is out of range - -1: @ shift and round mantissa - and ip, xh, #0x80000000 - mov r2, xl, lsl #3 - orr xl, ip, xl, lsr #29 - cmp r2, #0x80000000 - adc r0, xl, r3, lsl #2 - biceq r0, r0, #1 - RET - -2: @ either overflow or underflow - tst xh, #0x40000000 - bne 3f @ overflow - - @ check if denormalized value is possible - adds r2, r3, #(23 << 21) - andlt r0, xh, #0x80000000 @ too small, return signed 0. - RETc(lt) - - @ denormalize value so we can resume with the code above afterwards. - orr xh, xh, #0x00100000 - mov r2, r2, lsr #21 - rsb r2, r2, #24 - rsb ip, r2, #32 - movs r3, xl, lsl ip - mov xl, xl, lsr r2 - orrne xl, xl, #1 @ fold r3 for rounding considerations. - mov r3, xh, lsl #11 - mov r3, r3, lsr #11 - orr xl, xl, r3, lsl ip - mov r3, r3, lsr r2 - mov r3, r3, lsl #1 - b 1b - -3: @ chech for NAN - mvns r3, r2, asr #21 - bne 5f @ simple overflow - orrs r3, xl, xh, lsl #12 - movne r0, #0x7f000000 - orrne r0, r0, #0x00c00000 - RETc(ne) @ return NAN - -5: @ return INF with sign - and r0, xh, #0x80000000 - orr r0, r0, #0x7f000000 - orr r0, r0, #0x00800000 - RET - - FUNC_END aeabi_d2f - FUNC_END truncdfsf2 - -#endif /* L_truncdfsf2 */ |