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Diffstat (limited to 'arch/blackfin/lib/divsi3.S')
| -rw-r--r-- | arch/blackfin/lib/divsi3.S | 199 |
1 files changed, 0 insertions, 199 deletions
diff --git a/arch/blackfin/lib/divsi3.S b/arch/blackfin/lib/divsi3.S deleted file mode 100644 index ef2cd99efb89..000000000000 --- a/arch/blackfin/lib/divsi3.S +++ /dev/null @@ -1,199 +0,0 @@ -/* - * Copyright 2004-2009 Analog Devices Inc. - * - * Licensed under the Clear BSD license or the GPL-2 (or later) - * - * 16 / 32 bit signed division. - * Special cases : - * 1) If(numerator == 0) - * return 0 - * 2) If(denominator ==0) - * return positive max = 0x7fffffff - * 3) If(numerator == denominator) - * return 1 - * 4) If(denominator ==1) - * return numerator - * 5) If(denominator == -1) - * return -numerator - * - * Operand : R0 - Numerator (i) - * R1 - Denominator (i) - * R0 - Quotient (o) - * Registers Used : R2-R7,P0-P2 - * - */ - -.global ___divsi3; -.type ___divsi3, STT_FUNC; - -#ifdef CONFIG_ARITHMETIC_OPS_L1 -.section .l1.text -#else -.text -#endif - -.align 2; -___divsi3 : - - - R3 = R0 ^ R1; - R0 = ABS R0; - - CC = V; - - r3 = rot r3 by -1; - r1 = abs r1; /* now both positive, r3.30 means "negate result", - ** r3.31 means overflow, add one to result - */ - cc = r0 < r1; - if cc jump .Lret_zero; - r2 = r1 >> 15; - cc = r2; - if cc jump .Lidents; - r2 = r1 << 16; - cc = r2 <= r0; - if cc jump .Lidents; - - DIVS(R0, R1); - DIVQ(R0, R1); - DIVQ(R0, R1); - DIVQ(R0, R1); - DIVQ(R0, R1); - DIVQ(R0, R1); - DIVQ(R0, R1); - DIVQ(R0, R1); - DIVQ(R0, R1); - DIVQ(R0, R1); - DIVQ(R0, R1); - DIVQ(R0, R1); - DIVQ(R0, R1); - DIVQ(R0, R1); - DIVQ(R0, R1); - DIVQ(R0, R1); - DIVQ(R0, R1); - - R0 = R0.L (Z); - r1 = r3 >> 31; /* add overflow issue back in */ - r0 = r0 + r1; - r1 = -r0; - cc = bittst(r3, 30); - if cc r0 = r1; - RTS; - -/* Can't use the primitives. Test common identities. -** If the identity is true, return the value in R2. -*/ - -.Lidents: - CC = R1 == 0; /* check for divide by zero */ - IF CC JUMP .Lident_return; - - CC = R0 == 0; /* check for division of zero */ - IF CC JUMP .Lzero_return; - - CC = R0 == R1; /* check for identical operands */ - IF CC JUMP .Lident_return; - - CC = R1 == 1; /* check for divide by 1 */ - IF CC JUMP .Lident_return; - - R2.L = ONES R1; - R2 = R2.L (Z); - CC = R2 == 1; - IF CC JUMP .Lpower_of_two; - - /* Identities haven't helped either. - ** Perform the full division process. - */ - - P1 = 31; /* Set loop counter */ - - [--SP] = (R7:5); /* Push registers R5-R7 */ - R2 = -R1; - [--SP] = R2; - R2 = R0 << 1; /* R2 lsw of dividend */ - R6 = R0 ^ R1; /* Get sign */ - R5 = R6 >> 31; /* Shift sign to LSB */ - - R0 = 0 ; /* Clear msw partial remainder */ - R2 = R2 | R5; /* Shift quotient bit */ - R6 = R0 ^ R1; /* Get new quotient bit */ - - LSETUP(.Llst,.Llend) LC0 = P1; /* Setup loop */ -.Llst: R7 = R2 >> 31; /* record copy of carry from R2 */ - R2 = R2 << 1; /* Shift 64 bit dividend up by 1 bit */ - R0 = R0 << 1 || R5 = [SP]; - R0 = R0 | R7; /* and add carry */ - CC = R6 < 0; /* Check quotient(AQ) */ - /* we might be subtracting divisor (AQ==0) */ - IF CC R5 = R1; /* or we might be adding divisor (AQ==1)*/ - R0 = R0 + R5; /* do add or subtract, as indicated by AQ */ - R6 = R0 ^ R1; /* Generate next quotient bit */ - R5 = R6 >> 31; - /* Assume AQ==1, shift in zero */ - BITTGL(R5,0); /* tweak AQ to be what we want to shift in */ -.Llend: R2 = R2 + R5; /* and then set shifted-in value to - ** tweaked AQ. - */ - r1 = r3 >> 31; - r2 = r2 + r1; - cc = bittst(r3,30); - r0 = -r2; - if !cc r0 = r2; - SP += 4; - (R7:5)= [SP++]; /* Pop registers R6-R7 */ - RTS; - -.Lident_return: - CC = R1 == 0; /* check for divide by zero => 0x7fffffff */ - R2 = -1 (X); - R2 >>= 1; - IF CC JUMP .Ltrue_ident_return; - - CC = R0 == R1; /* check for identical operands => 1 */ - R2 = 1 (Z); - IF CC JUMP .Ltrue_ident_return; - - R2 = R0; /* assume divide by 1 => numerator */ - /*FALLTHRU*/ - -.Ltrue_ident_return: - R0 = R2; /* Return an identity value */ - R2 = -R2; - CC = bittst(R3,30); - IF CC R0 = R2; -.Lzero_return: - RTS; /* ...including zero */ - -.Lpower_of_two: - /* Y has a single bit set, which means it's a power of two. - ** That means we can perform the division just by shifting - ** X to the right the appropriate number of bits - */ - - /* signbits returns the number of sign bits, minus one. - ** 1=>30, 2=>29, ..., 0x40000000=>0. Which means we need - ** to shift right n-signbits spaces. It also means 0x80000000 - ** is a special case, because that *also* gives a signbits of 0 - */ - - R2 = R0 >> 31; - CC = R1 < 0; - IF CC JUMP .Ltrue_ident_return; - - R1.l = SIGNBITS R1; - R1 = R1.L (Z); - R1 += -30; - R0 = LSHIFT R0 by R1.L; - r1 = r3 >> 31; - r0 = r0 + r1; - R2 = -R0; // negate result if necessary - CC = bittst(R3,30); - IF CC R0 = R2; - RTS; - -.Lret_zero: - R0 = 0; - RTS; - -.size ___divsi3, .-___divsi3 |