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Diffstat (limited to 'arch/metag/lib/divsi3.S')
| -rw-r--r-- | arch/metag/lib/divsi3.S | 101 |
1 files changed, 0 insertions, 101 deletions
diff --git a/arch/metag/lib/divsi3.S b/arch/metag/lib/divsi3.S deleted file mode 100644 index 9e31abe..0000000 --- a/arch/metag/lib/divsi3.S +++ /dev/null @@ -1,101 +0,0 @@ -! SPDX-License-Identifier: GPL-2.0 -! Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007 -! Imagination Technologies Ltd -! -! Integer divide routines. -! - - .text - .global ___udivsi3 - .type ___udivsi3,function - .align 2 -___udivsi3: -!! -!! Since core is signed divide case, just set control variable -!! - MOV D1Re0,D0Ar2 ! Au already in A1Ar1, Bu -> D1Re0 - MOV D0Re0,#0 ! Result is 0 - MOV D0Ar4,#0 ! Return positive result - B $LIDMCUStart - .size ___udivsi3,.-___udivsi3 - -!! -!! 32-bit division signed i/p - passed signed 32-bit numbers -!! - .global ___divsi3 - .type ___divsi3,function - .align 2 -___divsi3: -!! -!! A already in D1Ar1, B already in D0Ar2 -> make B abs(B) -!! - MOV D1Re0,D0Ar2 ! A already in A1Ar1, B -> D1Re0 - MOV D0Re0,#0 ! Result is 0 - XOR D0Ar4,D1Ar1,D1Re0 ! D0Ar4 -ive if result is -ive - ABS D1Ar1,D1Ar1 ! abs(A) -> Au - ABS D1Re0,D1Re0 ! abs(B) -> Bu -$LIDMCUStart: - CMP D1Ar1,D1Re0 ! Is ( Au > Bu )? - LSR D1Ar3,D1Ar1,#2 ! Calculate (Au & (~3)) >> 2 - CMPHI D1Re0,D1Ar3 ! OR ( (Au & (~3)) <= (Bu << 2) )? - LSLSHI D1Ar3,D1Re0,#1 ! Buq = Bu << 1 - BLS $LIDMCUSetup ! Yes: Do normal divide -!! -!! Quick divide setup can assume that CurBit only needs to start at 2 -!! -$LIDMCQuick: - CMP D1Ar1,D1Ar3 ! ( A >= Buq )? - ADDCC D0Re0,D0Re0,#2 ! If yes result += 2 - SUBCC D1Ar1,D1Ar1,D1Ar3 ! and A -= Buq - CMP D1Ar1,D1Re0 ! ( A >= Bu )? - ADDCC D0Re0,D0Re0,#1 ! If yes result += 1 - SUBCC D1Ar1,D1Ar1,D1Re0 ! and A -= Bu - ORS D0Ar4,D0Ar4,D0Ar4 ! Return neg result? - NEG D0Ar2,D0Re0 ! Calculate neg result - MOVMI D0Re0,D0Ar2 ! Yes: Take neg result -$LIDMCRet: - MOV PC,D1RtP -!! -!! Setup for general unsigned divide code -!! -!! D0Re0 is used to form the result, already set to Zero -!! D1Re0 is the input Bu value, this gets trashed -!! D0Ar6 is curbit which is set to 1 at the start and shifted up -!! D0Ar4 is negative if we should return a negative result -!! D1Ar1 is the input Au value, eventually this holds the remainder -!! -$LIDMCUSetup: - CMP D1Ar1,D1Re0 ! Is ( Au < Bu )? - MOV D0Ar6,#1 ! Set curbit to 1 - BCS $LIDMCRet ! Yes: Return 0 remainder Au -!! -!! Calculate alignment using FFB instruction -!! - FFB D1Ar5,D1Ar1 ! Find first bit of Au - ANDN D1Ar5,D1Ar5,#31 ! Handle exceptional case. - ORN D1Ar5,D1Ar5,#31 ! if N bit set, set to 31 - FFB D1Ar3,D1Re0 ! Find first bit of Bu - ANDN D1Ar3,D1Ar3,#31 ! Handle exceptional case. - ORN D1Ar3,D1Ar3,#31 ! if N bit set, set to 31 - SUBS D1Ar3,D1Ar5,D1Ar3 ! calculate diff, ffbA - ffbB - MOV D0Ar2,D1Ar3 ! copy into bank 0 - LSLGT D1Re0,D1Re0,D1Ar3 ! ( > 0) ? left shift B - LSLGT D0Ar6,D0Ar6,D0Ar2 ! ( > 0) ? left shift curbit -!! -!! Now we start the divide proper, logic is -!! -!! if ( A >= B ) add curbit to result and subtract B from A -!! shift curbit and B down by 1 in either case -!! -$LIDMCLoop: - CMP D1Ar1, D1Re0 ! ( A >= B )? - ADDCC D0Re0, D0Re0, D0Ar6 ! If yes result += curbit - SUBCC D1Ar1, D1Ar1, D1Re0 ! and A -= B - LSRS D0Ar6, D0Ar6, #1 ! Shift down curbit, is it zero? - LSR D1Re0, D1Re0, #1 ! Shift down B - BNZ $LIDMCLoop ! Was single bit in curbit lost? - ORS D0Ar4,D0Ar4,D0Ar4 ! Return neg result? - NEG D0Ar2,D0Re0 ! Calculate neg result - MOVMI D0Re0,D0Ar2 ! Yes: Take neg result - MOV PC,D1RtP - .size ___divsi3,.-___divsi3 |
