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Diffstat (limited to 'src/pkg/runtime/vlop_arm.s')
| -rw-r--r-- | src/pkg/runtime/vlop_arm.s | 300 |
1 files changed, 0 insertions, 300 deletions
diff --git a/src/pkg/runtime/vlop_arm.s b/src/pkg/runtime/vlop_arm.s deleted file mode 100644 index 80f516ec4..000000000 --- a/src/pkg/runtime/vlop_arm.s +++ /dev/null @@ -1,300 +0,0 @@ -// Inferno's libkern/vlop-arm.s -// http://code.google.com/p/inferno-os/source/browse/libkern/vlop-arm.s -// -// Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved. -// Revisions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com). All rights reserved. -// Portions Copyright 2009 The Go Authors. All rights reserved. -// -// Permission is hereby granted, free of charge, to any person obtaining a copy -// of this software and associated documentation files (the "Software"), to deal -// in the Software without restriction, including without limitation the rights -// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell -// copies of the Software, and to permit persons to whom the Software is -// furnished to do so, subject to the following conditions: -// -// The above copyright notice and this permission notice shall be included in -// all copies or substantial portions of the Software. -// -// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR -// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, -// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE -// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER -// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, -// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN -// THE SOFTWARE. - -#include "zasm_GOOS_GOARCH.h" -#include "../../cmd/ld/textflag.h" - -arg=0 - -/* replaced use of R10 by R11 because the former can be the data segment base register */ - -TEXT _mulv(SB), NOSPLIT, $0 - MOVW 0(FP), R0 - MOVW 4(FP), R2 /* l0 */ - MOVW 8(FP), R11 /* h0 */ - MOVW 12(FP), R4 /* l1 */ - MOVW 16(FP), R5 /* h1 */ - MULLU R4, R2, (R7,R6) - MUL R11, R4, R8 - ADD R8, R7 - MUL R2, R5, R8 - ADD R8, R7 - MOVW R6, 0(R(arg)) - MOVW R7, 4(R(arg)) - RET - -// trampoline for _sfloat2. passes LR as arg0 and -// saves registers R0-R13 and CPSR on the stack. R0-R12 and CPSR flags can -// be changed by _sfloat2. -TEXT _sfloat(SB), NOSPLIT, $64-0 // 4 arg + 14*4 saved regs + cpsr - MOVW R14, 4(R13) - MOVW R0, 8(R13) - MOVW $12(R13), R0 - MOVM.IA.W [R1-R12], (R0) - MOVW $68(R13), R1 // correct for frame size - MOVW R1, 60(R13) - WORD $0xe10f1000 // mrs r1, cpsr - MOVW R1, 64(R13) - // Disable preemption of this goroutine during _sfloat2 by - // m->locks++ and m->locks-- around the call. - // Rescheduling this goroutine may cause the loss of the - // contents of the software floating point registers in - // m->freghi, m->freglo, m->fflag, if the goroutine is moved - // to a different m or another goroutine runs on this m. - // Rescheduling at ordinary function calls is okay because - // all registers are caller save, but _sfloat2 and the things - // that it runs are simulating the execution of individual - // program instructions, and those instructions do not expect - // the floating point registers to be lost. - // An alternative would be to move the software floating point - // registers into G, but they do not need to be kept at the - // usual places a goroutine reschedules (at function calls), - // so it would be a waste of 132 bytes per G. - MOVW m_locks(m), R1 - ADD $1, R1 - MOVW R1, m_locks(m) - MOVW $1, R1 - MOVW R1, m_softfloat(m) - BL runtime·_sfloat2(SB) - MOVW m_locks(m), R1 - SUB $1, R1 - MOVW R1, m_locks(m) - MOVW $0, R1 - MOVW R1, m_softfloat(m) - MOVW R0, 0(R13) - MOVW 64(R13), R1 - WORD $0xe128f001 // msr cpsr_f, r1 - MOVW $12(R13), R0 - // Restore R1-R8 and R11-R12, but ignore the saved R9 (m) and R10 (g). - // Both are maintained by the runtime and always have correct values, - // so there is no need to restore old values here. - // The g should not have changed, but m may have, if we were preempted - // and restarted on a different thread, in which case restoring the old - // value is incorrect and will cause serious confusion in the runtime. - MOVM.IA.W (R0), [R1-R8] - MOVW $52(R13), R0 - MOVM.IA.W (R0), [R11-R12] - MOVW 8(R13), R0 - RET - -// func udiv(n, d uint32) (q, r uint32) -// Reference: -// Sloss, Andrew et. al; ARM System Developer's Guide: Designing and Optimizing System Software -// Morgan Kaufmann; 1 edition (April 8, 2004), ISBN 978-1558608740 -q = 0 // input d, output q -r = 1 // input n, output r -s = 2 // three temporary variables -M = 3 -a = 11 -// Be careful: R(a) == R11 will be used by the linker for synthesized instructions. -TEXT udiv<>(SB),NOSPLIT,$-4 - CLZ R(q), R(s) // find normalizing shift - MOVW.S R(q)<<R(s), R(a) - MOVW $fast_udiv_tab<>-64(SB), R(M) - MOVBU.NE R(a)>>25(R(M)), R(a) // index by most significant 7 bits of divisor - - SUB.S $7, R(s) - RSB $0, R(q), R(M) // M = -q - MOVW.PL R(a)<<R(s), R(q) - - // 1st Newton iteration - MUL.PL R(M), R(q), R(a) // a = -q*d - BMI udiv_by_large_d - MULAWT R(a), R(q), R(q), R(q) // q approx q-(q*q*d>>32) - TEQ R(M)->1, R(M) // check for d=0 or d=1 - - // 2nd Newton iteration - MUL.NE R(M), R(q), R(a) - MOVW.NE $0, R(s) - MULAL.NE R(q), R(a), (R(q),R(s)) - BEQ udiv_by_0_or_1 - - // q now accurate enough for a remainder r, 0<=r<3*d - MULLU R(q), R(r), (R(q),R(s)) // q = (r * q) >> 32 - ADD R(M), R(r), R(r) // r = n - d - MULA R(M), R(q), R(r), R(r) // r = n - (q+1)*d - - // since 0 <= n-q*d < 3*d; thus -d <= r < 2*d - CMN R(M), R(r) // t = r-d - SUB.CS R(M), R(r), R(r) // if (t<-d || t>=0) r=r+d - ADD.CC $1, R(q) - ADD.PL R(M)<<1, R(r) - ADD.PL $2, R(q) - RET - -udiv_by_large_d: - // at this point we know d>=2^(31-6)=2^25 - SUB $4, R(a), R(a) - RSB $0, R(s), R(s) - MOVW R(a)>>R(s), R(q) - MULLU R(q), R(r), (R(q),R(s)) - MULA R(M), R(q), R(r), R(r) - - // q now accurate enough for a remainder r, 0<=r<4*d - CMN R(r)>>1, R(M) // if(r/2 >= d) - ADD.CS R(M)<<1, R(r) - ADD.CS $2, R(q) - CMN R(r), R(M) - ADD.CS R(M), R(r) - ADD.CS $1, R(q) - RET - -udiv_by_0_or_1: - // carry set if d==1, carry clear if d==0 - BCC udiv_by_0 - MOVW R(r), R(q) - MOVW $0, R(r) - RET - -udiv_by_0: - // The ARM toolchain expects it can emit references to DIV and MOD - // instructions. The linker rewrites each pseudo-instruction into - // a sequence that pushes two values onto the stack and then calls - // _divu, _modu, _div, or _mod (below), all of which have a 16-byte - // frame plus the saved LR. The traceback routine knows the expanded - // stack frame size at the pseudo-instruction call site, but it - // doesn't know that the frame has a non-standard layout. In particular, - // it expects to find a saved LR in the bottom word of the frame. - // Unwind the stack back to the pseudo-instruction call site, copy the - // saved LR where the traceback routine will look for it, and make it - // appear that panicdivide was called from that PC. - MOVW 0(R13), LR - ADD $20, R13 - MOVW 8(R13), R1 // actual saved LR - MOVW R1, 0(R13) // expected here for traceback - B runtime·panicdivide(SB) - -TEXT fast_udiv_tab<>(SB),NOSPLIT,$-4 - // var tab [64]byte - // tab[0] = 255; for i := 1; i <= 63; i++ { tab[i] = (1<<14)/(64+i) } - // laid out here as little-endian uint32s - WORD $0xf4f8fcff - WORD $0xe6eaedf0 - WORD $0xdadde0e3 - WORD $0xcfd2d4d7 - WORD $0xc5c7cacc - WORD $0xbcbec0c3 - WORD $0xb4b6b8ba - WORD $0xacaeb0b2 - WORD $0xa5a7a8aa - WORD $0x9fa0a2a3 - WORD $0x999a9c9d - WORD $0x93949697 - WORD $0x8e8f9092 - WORD $0x898a8c8d - WORD $0x85868788 - WORD $0x81828384 - -// The linker will pass numerator in R(TMP), and it also -// expects the result in R(TMP) -TMP = 11 - -TEXT _divu(SB), NOSPLIT, $16 - MOVW R(q), 4(R13) - MOVW R(r), 8(R13) - MOVW R(s), 12(R13) - MOVW R(M), 16(R13) - - MOVW R(TMP), R(r) /* numerator */ - MOVW 0(FP), R(q) /* denominator */ - BL udiv<>(SB) - MOVW R(q), R(TMP) - MOVW 4(R13), R(q) - MOVW 8(R13), R(r) - MOVW 12(R13), R(s) - MOVW 16(R13), R(M) - RET - -TEXT _modu(SB), NOSPLIT, $16 - MOVW R(q), 4(R13) - MOVW R(r), 8(R13) - MOVW R(s), 12(R13) - MOVW R(M), 16(R13) - - MOVW R(TMP), R(r) /* numerator */ - MOVW 0(FP), R(q) /* denominator */ - BL udiv<>(SB) - MOVW R(r), R(TMP) - MOVW 4(R13), R(q) - MOVW 8(R13), R(r) - MOVW 12(R13), R(s) - MOVW 16(R13), R(M) - RET - -TEXT _div(SB),NOSPLIT,$16 - MOVW R(q), 4(R13) - MOVW R(r), 8(R13) - MOVW R(s), 12(R13) - MOVW R(M), 16(R13) - MOVW R(TMP), R(r) /* numerator */ - MOVW 0(FP), R(q) /* denominator */ - CMP $0, R(r) - BGE d1 - RSB $0, R(r), R(r) - CMP $0, R(q) - BGE d2 - RSB $0, R(q), R(q) -d0: - BL udiv<>(SB) /* none/both neg */ - MOVW R(q), R(TMP) - B out1 -d1: - CMP $0, R(q) - BGE d0 - RSB $0, R(q), R(q) -d2: - BL udiv<>(SB) /* one neg */ - RSB $0, R(q), R(TMP) -out1: - MOVW 4(R13), R(q) - MOVW 8(R13), R(r) - MOVW 12(R13), R(s) - MOVW 16(R13), R(M) - RET - -TEXT _mod(SB),NOSPLIT,$16 - MOVW R(q), 4(R13) - MOVW R(r), 8(R13) - MOVW R(s), 12(R13) - MOVW R(M), 16(R13) - MOVW R(TMP), R(r) /* numerator */ - MOVW 0(FP), R(q) /* denominator */ - CMP $0, R(q) - RSB.LT $0, R(q), R(q) - CMP $0, R(r) - BGE m1 - RSB $0, R(r), R(r) - BL udiv<>(SB) /* neg numerator */ - RSB $0, R(r), R(TMP) - B out -m1: - BL udiv<>(SB) /* pos numerator */ - MOVW R(r), R(TMP) -out: - MOVW 4(R13), R(q) - MOVW 8(R13), R(r) - MOVW 12(R13), R(s) - MOVW 16(R13), R(M) - RET |