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// picoChip ASM file

//.file "popcounthi2.S"

//

//   Support for 16-bit population count.

//

//   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

//   .

.section .text

// The following code (taken from a newsgroup posting) was compiled, and then

// hand assembled (a similar version is given in the Hacker's Delight

// book, chapter 5).

//

// int

// popcount (int value)

// {

//    value = ((value & 0xAAAA) >> 1) + (value & 0x5555);

//    value = ((value & 0xCCCC) >> 2) + (value & 0x3333);

//    value = ((value & 0xF0F0) >> 4) + (value & 0x0F0F);

//    return ((value & 0xFF00) >> 8) + (value & 0x00FF);

// }

//

// This assembly function is approx. 20x faster than a naive loop

// implementation of the population count, but about 30% bigger

// (45 bytes v. 34 bytes).

.align 8

.global ___popcounthi2

___popcounthi2:

_picoMark_FUNCTION_BEGIN=

// picoChip Function Prologue : &___popcounthi2 = 0 bytes

        AND.0 [LSR R0,1],21845,R0 \ AND.1 R0,21845,R5

        ADD.0 R0,R5,R0

        AND.0 [LSR R0,2],13107,R0 \ AND.1 R0,13107,R5

        ADD.0 R0,R5,R0 \ COPY.1 1807,R2

        AND.0 [LSR R0,4],R2,R0 \ AND.1 R0,3855,R5

        ADD.0 R0,R5,R0

        JR (R12) \ AND.0 R0, 255, R5

=->     ADD.0 [LSR R0,8],R5,R0

_picoMark_FUNCTION_END=

// picoChip Function Epilogue : ___popcounthi2

//============================================================================

// 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 0x0    // <-- 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#5f# 16#70# 16#6f# 16#70# 16#63# 16#6f# 16#75# 16#6e# 16#74# 16#68# 16#69# 16#32# 16#0# // Function name `__popcounthi2'

.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