diff options
Diffstat (limited to 'config/picochip/libgccExtras/udivmodsi4.asm')
| -rw-r--r-- | config/picochip/libgccExtras/udivmodsi4.asm | 323 |
1 files changed, 323 insertions, 0 deletions
diff --git a/config/picochip/libgccExtras/udivmodsi4.asm b/config/picochip/libgccExtras/udivmodsi4.asm new file mode 100644 index 00000000000..b992206af69 --- /dev/null +++ b/config/picochip/libgccExtras/udivmodsi4.asm @@ -0,0 +1,323 @@ +// picoChip ASM file +// +// Support for 32-bit unsigned division/modulus. +// +// Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc. +// Contributed by picoChip Designs 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 2, or (at your option) any +// later version. +// +// In addition to the permissions in the GNU General Public License, the +// Free Software Foundation gives you unlimited permission to link the +// compiled version of this file into combinations with other programs, +// and to distribute those combinations without any restriction coming +// from the use of this file. (The General Public License restrictions +// do apply in other respects; for example, they cover modification of +// the file, and distribution when not linked into a combine +// executable.) +// +// 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. +// +// You should have received a copy of the GNU General Public License +// along with this program; see the file COPYING. If not, write to +// the Free Software Foundation, 51 Franklin Street, Fifth Floor, +// Boston, MA 02110-1301, USA. + +.section .text + +.align 8 +.global __udivmodsi4 +__udivmodsi4: +_picoMark_FUNCTION_BEGIN= +// picoChip Function Prologue : &__udivmodsi4 = 24 bytes + + // Schedule the register saves alongside the special cases, so that + // if the special cases fail, the registers will have already + // been stored onto the stack. + SUB.0 R3,R1,r15 \ STL R[13:12],(FP)-1 + BHS skipCommonCase \ STL R[9:8],(FP)-4 +=-> SUB.0 R2,1,r15 \ STL R[11:10],(FP)-3 + +_L2: + // Flags set above, and in _L2 caller. + BNE restOfCode +=-> SUB.0 R3,0,r15 + BNE restOfCode +=-> COPY.0 R0,R4 \ COPY.1 R1,R5 + JR (R12) // Return to caller +=-> COPY.0 0,R6 \ COPY.1 0,R7 + // Never reach here + +skipCommonCase: + SUB.0 R3,R1,r15 + BNE _L3 // (Reversed branch) +=-> SUB.0 R2,R0,r15 // Must be set in delay slot, so ready by _L9 + +_L9: + BLO _L2 // (Reversed branch) +=-> SUB.0 R2,1,r15 + +_L3: + SUB.0 R2,R0,r15 + BEQ _L10 // (Reversed branch) +=-> SUB.0 R1,R3,r15 // Set flags for branch at _L10 + +_L4: + // greater than + COPY.0 0,R4 \ COPY.1 0,R5 \ JR (R12) // Return to caller +=-> COPY.0 R0,R6 \ COPY.1 R1,R7 + // Doesn't reach here. + +_L10: + // Flags set in _L10 call delay slot. + BNE _L4 +=-> COPY.0 1,R4 \ COPY.1 0,R5 + JR (R12) // Return to caller +=-> COPY.0 0,R6 \ COPY.1 0,R7 + +restOfCode: + +// Prologue + + // Register saves scheduled alongside special cases above. + ADD.0 FP,-20,FP \ STW R14,(FP)-4 + + // The following can be scheduled together. + // dividend in R[9:8] (from R[1:0]) + // divisor in R[7:6] (from R[3:2]) + // R14 := clzsi2 (dividend) + // R0 := clzsi2 (divisor) + JL (&__clzsi2) \ COPY.0 R0,R8 \ COPY.1 R1,R9 +=-> COPY.0 R2,R6 \ COPY.1 R3,R7 + COPY.0 R0,R14 \ JL (&__clzsi2) +=-> COPY.0 R6,R0 \ COPY.1 R7,R1 + + // R14 := R0 - R14 + SUB.0 R0,R14,R14 + + ADD.0 R14,1,R0 // R0 := R14 + 1 (HI) + + // R[11:10] = R[7,6] << R14 + SUB.0 15,R14,r15 + LSL.0 R6,R14,R11 \ BLT setupDivstepLoop +=-> SUB.0 0,R14,R4 \ COPY.1 0,R10 + + // Zero shift is a special case. Shifting by zero within a 16-bit + // source object is fine, but don't execute the OR of the right-shift + // into the final result. + LSL.0 R7,R14,R11 \ BEQ setupDivstepLoop +=-> LSL.0 R6,R14,R10 + + LSR.0 R6,R4,R4 + OR.0 R11,R4,R11 + +setupDivstepLoop: + + // R[5:4] := R[9:8] (SI) + COPY.0 R8,R4 \ COPY.1 R9,R5 + COPY.0 0,R6 \ COPY.1 R0,R8 + + // Store original value of loopCount for use after the loop. + // The Subtraction is handled in the tail of the loop iteration + // after this point. + SUB.0 R4,R10,R0 \ COPY.1 R8,R14 + + // workingResult in R4,5,6 + // temps in r0,1,2 and r7 + // alignedDivisor in R10,11 + // loopCount in r8 + // r3, r9 scratch, used for renaming. + +loopStart: + // R0 := R4 - zeroExtend (R10) - only need 33-bits (i.e., 48-bits) + SUBB.0 R5,R11,R1 \ LSR.1 R0,15,R3 + SUBB.0 R6,0,R2 \ LSR.1 R1,15,R6 + + // if (carry) goto shiftOnly + SUB.0 R8,1,R8 \ BNE shiftOnly +=-> LSR.0 R4,15,R7 \ LSL.1 R1,1,R9 + + OR.0 [LSL R0,1],1,R4 \ BNE loopStart +=-> SUB.0 R4,R10,R0 \ OR.1 R9,R3,R5 + + BRA loopEnd + +shiftOnly: + + OR.0 [LSL R5,1],R7,R5 \ BNE loopStart \ LSR.1 R5,15,R6 +=-> SUB.0 [LSL R4,1],R10,R0 \LSL.1 R4,1,R4 + +// End of loop +loopEnd: + + // Schedule the computation of the upper word after shifting + // alongside the decision over whether to branch, and the register + // restores. + // R10 is filled with a useful constant. + SUB.0 15,r14,r15 \ LDL (FP)4,R[13:12] + SUB.1 0,R14,R1 // Don't set flags! + LSL.0 R6,R1,R3 \ LDL (FP)-4,R[9:8] + + BLT remainderHasMoreThan16Bits \ LSR.0 R5,R14,R7 \ COPY.1 -1,R10 +=-> LSL.0 R5,R1,R2 \ OR.1 R7,R3,R3 + + LSR.0 R4,R14,R3 \ COPY.1 R3,R7 + BRA epilogue \ LSR.0 -1,R1,R0 \ COPY.1 0,R5 +=-> OR.0 R3,R2,R6 \ AND.1 R0,R4,R4 + +remainderHasMoreThan16Bits: + + LSL.0 R10,R14,R1 \ COPY.1 R3,R6 + XOR.0 R10,R1,R1 \ COPY.1 0,R7 + AND.0 R1,R5,R5 + +epilogue: + + JR (R12) \ LDW (FP)-4,R14 +=-> LDL (FP)-3,R[11:10] + +_picoMark_FUNCTION_END= + +// picoChip Function Epilogue : udivmodsi4 + +//============================================================================ +// 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 0x18 // <-- 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#75# 16#64# 16#69# 16#76# 16#6d# 16#6f# 16#64# 16#73# 16#69# 16#34# 16#0# // Function name `_udivmodsi4' +.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 |