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// picoChip ASM file
//
// Support for 32-bit signed division/modulus.
//
// Copyright (C) 2003, 2004, 2005, 2008, 2009 Free Software Foundation, Inc.
// Contributed by Picochip Ltd.
// Maintained by Daniel Towner (daniel.towner@picochip.com)
//
// 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 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/>.
.section .text
.align 8
.global __divmodsi4
__divmodsi4:
_picoMark_FUNCTION_BEGIN=
// picoChip Function Prologue : &__divmodsi4 = 8 bytes
// Note: optimising for size is preferred over optimising for speed.
// Note: the frame is setup throughout the following instructions,
// and is complete at the point the udivmodsi4 function is called.
// Note that R9 is encoded with a pattern which indicates
// whether the remainder and quotient should be negated on
// completion. The MSB is set to the sign of the dividend
// (i.e., the sign of the remainder), while the LSB encodes
// the XOR of the two input's signs (i.e., the sign of the
// quotient.
// If dividend is negative, invert the dividend and flag.
ASR.0 r1,15,r4
BEQ dividendNotNegative
=-> STL R[9:8],(FP)-2
// Dividend is negative - negate dividend.
SUB.0 0,R0,R0
SUBB.0 0,R1,R1
dividendNotNegative:
// If divisor is negative, invert the divisor.
AND.0 [lsr r3,15],1,r5
SUB.0 R3,0, r15
BGE divisorNotNegative
=-> XOR.0 r4,r5,r9
// Divisor is negative - negate divisor.
SUB.0 0,R2,R2
SUBB.0 0,R3,R3
divisorNotNegative:
STL R[13:12],(FP)-1 \ JL (&__udivmodsi4)
=-> SUB.0 FP,8,FP // udivmodsi expects the frame to be valid still.
// The LSB of R9 indicates whether the quotient should be negated.
AND.0 r9,1,r15
BEQ skipQuotientNegation
=-> LDL (FP)1,R[13:12] // Convenient point to restore link/fp
SUB.0 0,R4,R4
SUBB.0 0,R5,R5
skipQuotientNegation:
// The MSB of R9 indicates whether the remainder should be negated.
ASR.0 R9,15,r15
BEQ epilogue
SUB.0 0,R6,R6
SUBB.0 0,R7,R7
epilogue:
JR (R12)
=-> LDL (FP)-2,R[9:8]
_picoMark_FUNCTION_END=
// picoChip Function Epilogue : __divmodsi4
//============================================================================
// All DWARF information between this marker, and the END OF DWARF
// marker should be included in the source file. Search for
// FUNCTION_STACK_SIZE_GOES_HERE and FUNCTION NAME GOES HERE, and
// provide the relevent information. Add markers called
// _picoMark_FUNCTION_BEGIN and _picoMark_FUNCTION_END around the
// function in question.
//============================================================================
//============================================================================
// Frame information.
//============================================================================
.section .debug_frame
_picoMark_DebugFrame=
// Common CIE header.
.unalignedInitLong _picoMark_CieEnd-_picoMark_CieBegin
_picoMark_CieBegin=
.unalignedInitLong 0xffffffff
.initByte 0x1 // CIE Version
.ascii 16#0# // CIE Augmentation
.uleb128 0x1 // CIE Code Alignment Factor
.sleb128 2 // CIE Data Alignment Factor
.initByte 0xc // CIE RA Column
.initByte 0xc // DW_CFA_def_cfa
.uleb128 0xd
.uleb128 0x0
.align 2
_picoMark_CieEnd=
// FDE
_picoMark_LSFDE0I900821033007563=
.unalignedInitLong _picoMark_FdeEnd-_picoMark_FdeBegin
_picoMark_FdeBegin=
.unalignedInitLong _picoMark_DebugFrame // FDE CIE offset
.unalignedInitWord _picoMark_FUNCTION_BEGIN // FDE initial location
.unalignedInitWord _picoMark_FUNCTION_END-_picoMark_FUNCTION_BEGIN
.initByte 0xe // DW_CFA_def_cfa_offset
.uleb128 0x8 // <-- FUNCTION_STACK_SIZE_GOES_HERE
.initByte 0x4 // DW_CFA_advance_loc4
.unalignedInitLong _picoMark_FUNCTION_END-_picoMark_FUNCTION_BEGIN
.initByte 0xe // DW_CFA_def_cfa_offset
.uleb128 0x0
.align 2
_picoMark_FdeEnd=
//============================================================================
// Abbrevation information.
//============================================================================
.section .debug_abbrev
_picoMark_ABBREVIATIONS=
.section .debug_abbrev
.uleb128 0x1 // (abbrev code)
.uleb128 0x11 // (TAG: DW_TAG_compile_unit)
.initByte 0x1 // DW_children_yes
.uleb128 0x10 // (DW_AT_stmt_list)
.uleb128 0x6 // (DW_FORM_data4)
.uleb128 0x12 // (DW_AT_high_pc)
.uleb128 0x1 // (DW_FORM_addr)
.uleb128 0x11 // (DW_AT_low_pc)
.uleb128 0x1 // (DW_FORM_addr)
.uleb128 0x25 // (DW_AT_producer)
.uleb128 0x8 // (DW_FORM_string)
.uleb128 0x13 // (DW_AT_language)
.uleb128 0x5 // (DW_FORM_data2)
.uleb128 0x3 // (DW_AT_name)
.uleb128 0x8 // (DW_FORM_string)
.initByte 0x0
.initByte 0x0
.uleb128 0x2 ;# (abbrev code)
.uleb128 0x2e ;# (TAG: DW_TAG_subprogram)
.initByte 0x0 ;# DW_children_no
.uleb128 0x3 ;# (DW_AT_name)
.uleb128 0x8 ;# (DW_FORM_string)
.uleb128 0x11 ;# (DW_AT_low_pc)
.uleb128 0x1 ;# (DW_FORM_addr)
.uleb128 0x12 ;# (DW_AT_high_pc)
.uleb128 0x1 ;# (DW_FORM_addr)
.initByte 0x0
.initByte 0x0
.initByte 0x0
//============================================================================
// Line information. DwarfLib requires this to be present, but it can
// be empty.
//============================================================================
.section .debug_line
_picoMark_LINES=
//============================================================================
// Debug Information
//============================================================================
.section .debug_info
//Fixed header.
.unalignedInitLong _picoMark_DEBUG_INFO_END-_picoMark_DEBUG_INFO_BEGIN
_picoMark_DEBUG_INFO_BEGIN=
.unalignedInitWord 0x2
.unalignedInitLong _picoMark_ABBREVIATIONS
.initByte 0x2
// Compile unit information.
.uleb128 0x1 // (DIE 0xb) DW_TAG_compile_unit)
.unalignedInitLong _picoMark_LINES
.unalignedInitWord _picoMark_FUNCTION_END
.unalignedInitWord _picoMark_FUNCTION_BEGIN
// Producer is `picoChip'
.ascii 16#70# 16#69# 16#63# 16#6f# 16#43# 16#68# 16#69# 16#70# 16#00#
.unalignedInitWord 0xcafe // ASM language
.ascii 16#0# // Name. DwarfLib expects this to be present.
.uleb128 0x2 ;# (DIE DW_TAG_subprogram)
// FUNCTION NAME GOES HERE. Use `echo name | od -t x1' to get the hex. Each hex
// digit is specified using the format 16#XX#
.ascii 16#5f# 16#64# 16#69# 16#76# 16#6d# 16#6f# 16#64# 16#73# 16#69# 16#34# 16#0# // Function name `_divmodsi4'
.unalignedInitWord _picoMark_FUNCTION_BEGIN // DW_AT_low_pc
.unalignedInitWord _picoMark_FUNCTION_END // DW_AT_high_pc
.initByte 0x0 // end of compile unit children.
_picoMark_DEBUG_INFO_END=
//============================================================================
// END OF DWARF
//============================================================================
.section .endFile
// End of picoChip ASM file
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