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Diffstat (limited to 'src/core/arm/dyncom/arm_dyncom_thumb.cpp')
-rw-r--r-- | src/core/arm/dyncom/arm_dyncom_thumb.cpp | 390 |
1 files changed, 0 insertions, 390 deletions
diff --git a/src/core/arm/dyncom/arm_dyncom_thumb.cpp b/src/core/arm/dyncom/arm_dyncom_thumb.cpp deleted file mode 100644 index 2a3dd0f53..000000000 --- a/src/core/arm/dyncom/arm_dyncom_thumb.cpp +++ /dev/null @@ -1,390 +0,0 @@ -// Copyright 2012 Michael Kang, 2014 Citra Emulator Project -// Licensed under GPLv2 or any later version -// Refer to the license.txt file included. - -#include <cstddef> - -// We can provide simple Thumb simulation by decoding the Thumb instruction into its corresponding -// ARM instruction, and using the existing ARM simulator. - -#include "core/arm/dyncom/arm_dyncom_thumb.h" -#include "core/arm/skyeye_common/armsupp.h" - -// Decode a 16bit Thumb instruction. The instruction is in the low 16-bits of the tinstr field, -// with the following Thumb instruction held in the high 16-bits. Passing in two Thumb instructions -// allows easier simulation of the special dual BL instruction. - -ThumbDecodeStatus TranslateThumbInstruction(u32 addr, u32 instr, u32* ainstr, u32* inst_size) { - ThumbDecodeStatus valid = ThumbDecodeStatus::UNINITIALIZED; - u32 tinstr = GetThumbInstruction(instr, addr); - - *ainstr = 0xDEADC0DE; // Debugging to catch non updates - - switch ((tinstr & 0xF800) >> 11) { - case 0: // LSL - case 1: // LSR - case 2: // ASR - *ainstr = 0xE1B00000 // base opcode - | ((tinstr & 0x1800) >> (11 - 5)) // shift type - | ((tinstr & 0x07C0) << (7 - 6)) // imm5 - | ((tinstr & 0x0038) >> 3) // Rs - | ((tinstr & 0x0007) << 12); // Rd - break; - - case 3: // ADD/SUB - { - static const u32 subset[4] = { - 0xE0900000, // ADDS Rd,Rs,Rn - 0xE0500000, // SUBS Rd,Rs,Rn - 0xE2900000, // ADDS Rd,Rs,#imm3 - 0xE2500000 // SUBS Rd,Rs,#imm3 - }; - // It is quicker indexing into a table, than performing switch or conditionals: - *ainstr = subset[(tinstr & 0x0600) >> 9] // base opcode - | ((tinstr & 0x01C0) >> 6) // Rn or imm3 - | ((tinstr & 0x0038) << (16 - 3)) // Rs - | ((tinstr & 0x0007) << (12 - 0)); // Rd - } break; - - case 4: // MOV - case 5: // CMP - case 6: // ADD - case 7: // SUB - { - static const u32 subset[4] = { - 0xE3B00000, // MOVS Rd,#imm8 - 0xE3500000, // CMP Rd,#imm8 - 0xE2900000, // ADDS Rd,Rd,#imm8 - 0xE2500000, // SUBS Rd,Rd,#imm8 - }; - - *ainstr = subset[(tinstr & 0x1800) >> 11] // base opcode - | ((tinstr & 0x00FF) >> 0) // imm8 - | ((tinstr & 0x0700) << (16 - 8)) // Rn - | ((tinstr & 0x0700) << (12 - 8)); // Rd - } break; - - case 8: // Arithmetic and high register transfers - - // TODO: Since the subsets for both Format 4 and Format 5 instructions are made up of - // different ARM encodings, we could save the following conditional, and just have one - // large subset - - if ((tinstr & (1 << 10)) == 0) { - enum otype { t_norm, t_shift, t_neg, t_mul }; - - static const struct { - u32 opcode; - otype type; - } subset[16] = { - {0xE0100000, t_norm}, // ANDS Rd,Rd,Rs - {0xE0300000, t_norm}, // EORS Rd,Rd,Rs - {0xE1B00010, t_shift}, // MOVS Rd,Rd,LSL Rs - {0xE1B00030, t_shift}, // MOVS Rd,Rd,LSR Rs - {0xE1B00050, t_shift}, // MOVS Rd,Rd,ASR Rs - {0xE0B00000, t_norm}, // ADCS Rd,Rd,Rs - {0xE0D00000, t_norm}, // SBCS Rd,Rd,Rs - {0xE1B00070, t_shift}, // MOVS Rd,Rd,ROR Rs - {0xE1100000, t_norm}, // TST Rd,Rs - {0xE2700000, t_neg}, // RSBS Rd,Rs,#0 - {0xE1500000, t_norm}, // CMP Rd,Rs - {0xE1700000, t_norm}, // CMN Rd,Rs - {0xE1900000, t_norm}, // ORRS Rd,Rd,Rs - {0xE0100090, t_mul}, // MULS Rd,Rd,Rs - {0xE1D00000, t_norm}, // BICS Rd,Rd,Rs - {0xE1F00000, t_norm} // MVNS Rd,Rs - }; - - *ainstr = subset[(tinstr & 0x03C0) >> 6].opcode; // base - - switch (subset[(tinstr & 0x03C0) >> 6].type) { - case t_norm: - *ainstr |= ((tinstr & 0x0007) << 16) // Rn - | ((tinstr & 0x0007) << 12) // Rd - | ((tinstr & 0x0038) >> 3); // Rs - break; - case t_shift: - *ainstr |= ((tinstr & 0x0007) << 12) // Rd - | ((tinstr & 0x0007) >> 0) // Rm - | ((tinstr & 0x0038) << (8 - 3)); // Rs - break; - case t_neg: - *ainstr |= ((tinstr & 0x0007) << 12) // Rd - | ((tinstr & 0x0038) << (16 - 3)); // Rn - break; - case t_mul: - *ainstr |= ((tinstr & 0x0007) << 16) // Rd - | ((tinstr & 0x0007) << 8) // Rs - | ((tinstr & 0x0038) >> 3); // Rm - break; - } - } else { - u32 Rd = ((tinstr & 0x0007) >> 0); - u32 Rs = ((tinstr & 0x0078) >> 3); - - if (tinstr & (1 << 7)) - Rd += 8; - - switch ((tinstr & 0x03C0) >> 6) { - case 0x0: // ADD Rd,Rd,Rs - case 0x1: // ADD Rd,Rd,Hs - case 0x2: // ADD Hd,Hd,Rs - case 0x3: // ADD Hd,Hd,Hs - *ainstr = 0xE0800000 // base - | (Rd << 16) // Rn - | (Rd << 12) // Rd - | (Rs << 0); // Rm - break; - case 0x4: // CMP Rd,Rs - case 0x5: // CMP Rd,Hs - case 0x6: // CMP Hd,Rs - case 0x7: // CMP Hd,Hs - *ainstr = 0xE1500000 // base - | (Rd << 16) // Rn - | (Rs << 0); // Rm - break; - case 0x8: // MOV Rd,Rs - case 0x9: // MOV Rd,Hs - case 0xA: // MOV Hd,Rs - case 0xB: // MOV Hd,Hs - *ainstr = 0xE1A00000 // base - | (Rd << 12) // Rd - | (Rs << 0); // Rm - break; - case 0xC: // BX Rs - case 0xD: // BX Hs - *ainstr = 0xE12FFF10 // base - | ((tinstr & 0x0078) >> 3); // Rd - break; - case 0xE: // BLX - case 0xF: // BLX - *ainstr = 0xE1200030 // base - | (Rs << 0); // Rm - break; - } - } - break; - - case 9: // LDR Rd,[PC,#imm8] - *ainstr = 0xE59F0000 // base - | ((tinstr & 0x0700) << (12 - 8)) // Rd - | ((tinstr & 0x00FF) << (2 - 0)); // off8 - break; - - case 10: - case 11: { - static const u32 subset[8] = { - 0xE7800000, // STR Rd,[Rb,Ro] - 0xE18000B0, // STRH Rd,[Rb,Ro] - 0xE7C00000, // STRB Rd,[Rb,Ro] - 0xE19000D0, // LDRSB Rd,[Rb,Ro] - 0xE7900000, // LDR Rd,[Rb,Ro] - 0xE19000B0, // LDRH Rd,[Rb,Ro] - 0xE7D00000, // LDRB Rd,[Rb,Ro] - 0xE19000F0 // LDRSH Rd,[Rb,Ro] - }; - - *ainstr = subset[(tinstr & 0xE00) >> 9] // base - | ((tinstr & 0x0007) << (12 - 0)) // Rd - | ((tinstr & 0x0038) << (16 - 3)) // Rb - | ((tinstr & 0x01C0) >> 6); // Ro - } break; - - case 12: // STR Rd,[Rb,#imm5] - case 13: // LDR Rd,[Rb,#imm5] - case 14: // STRB Rd,[Rb,#imm5] - case 15: // LDRB Rd,[Rb,#imm5] - { - static const u32 subset[4] = { - 0xE5800000, // STR Rd,[Rb,#imm5] - 0xE5900000, // LDR Rd,[Rb,#imm5] - 0xE5C00000, // STRB Rd,[Rb,#imm5] - 0xE5D00000 // LDRB Rd,[Rb,#imm5] - }; - // The offset range defends on whether we are transferring a byte or word value: - *ainstr = subset[(tinstr & 0x1800) >> 11] // base - | ((tinstr & 0x0007) << (12 - 0)) // Rd - | ((tinstr & 0x0038) << (16 - 3)) // Rb - | ((tinstr & 0x07C0) >> (6 - ((tinstr & (1 << 12)) ? 0 : 2))); // off5 - } break; - - case 16: // STRH Rd,[Rb,#imm5] - case 17: // LDRH Rd,[Rb,#imm5] - *ainstr = ((tinstr & (1 << 11)) // base - ? 0xE1D000B0 // LDRH - : 0xE1C000B0) // STRH - | ((tinstr & 0x0007) << (12 - 0)) // Rd - | ((tinstr & 0x0038) << (16 - 3)) // Rb - | ((tinstr & 0x01C0) >> (6 - 1)) // off5, low nibble - | ((tinstr & 0x0600) >> (9 - 8)); // off5, high nibble - break; - - case 18: // STR Rd,[SP,#imm8] - case 19: // LDR Rd,[SP,#imm8] - *ainstr = ((tinstr & (1 << 11)) // base - ? 0xE59D0000 // LDR - : 0xE58D0000) // STR - | ((tinstr & 0x0700) << (12 - 8)) // Rd - | ((tinstr & 0x00FF) << 2); // off8 - break; - - case 20: // ADD Rd,PC,#imm8 - case 21: // ADD Rd,SP,#imm8 - - if ((tinstr & (1 << 11)) == 0) { - - // NOTE: The PC value used here should by word aligned. We encode shift-left-by-2 in the - // rotate immediate field, so no shift of off8 is needed. - - *ainstr = 0xE28F0F00 // base - | ((tinstr & 0x0700) << (12 - 8)) // Rd - | (tinstr & 0x00FF); // off8 - } else { - // We encode shift-left-by-2 in the rotate immediate field, so no shift of off8 is - // needed. - *ainstr = 0xE28D0F00 // base - | ((tinstr & 0x0700) << (12 - 8)) // Rd - | (tinstr & 0x00FF); // off8 - } - break; - - case 22: - case 23: - if ((tinstr & 0x0F00) == 0x0000) { - // NOTE: The instruction contains a shift left of 2 equivalent (implemented as ROR #30): - *ainstr = ((tinstr & (1 << 7)) // base - ? 0xE24DDF00 // SUB - : 0xE28DDF00) // ADD - | (tinstr & 0x007F); // off7 - } else if ((tinstr & 0x0F00) == 0x0e00) { - // BKPT - *ainstr = 0xEF000000 // base - | BITS(tinstr, 0, 3) // imm4 field; - | (BITS(tinstr, 4, 7) << 8); // beginning 4 bits of imm12 - } else if ((tinstr & 0x0F00) == 0x0200) { - static const u32 subset[4] = { - 0xE6BF0070, // SXTH - 0xE6AF0070, // SXTB - 0xE6FF0070, // UXTH - 0xE6EF0070, // UXTB - }; - - *ainstr = subset[BITS(tinstr, 6, 7)] // base - | (BITS(tinstr, 0, 2) << 12) // Rd - | BITS(tinstr, 3, 5); // Rm - } else if ((tinstr & 0x0F00) == 0x600) { - if (BIT(tinstr, 5) == 0) { - // SETEND - *ainstr = 0xF1010000 // base - | (BIT(tinstr, 3) << 9); // endian specifier - } else { - // CPS - *ainstr = 0xF1080000 // base - | (BIT(tinstr, 0) << 6) // fiq bit - | (BIT(tinstr, 1) << 7) // irq bit - | (BIT(tinstr, 2) << 8) // abort bit - | (BIT(tinstr, 4) << 18); // enable bit - } - } else if ((tinstr & 0x0F00) == 0x0a00) { - static const u32 subset[4] = { - 0xE6BF0F30, // REV - 0xE6BF0FB0, // REV16 - 0, // undefined - 0xE6FF0FB0, // REVSH - }; - - size_t subset_index = BITS(tinstr, 6, 7); - - if (subset_index == 2) { - valid = ThumbDecodeStatus::UNDEFINED; - } else { - *ainstr = subset[subset_index] // base - | (BITS(tinstr, 0, 2) << 12) // Rd - | BITS(tinstr, 3, 5); // Rm - } - } else { - static const u32 subset[4] = { - 0xE92D0000, // STMDB sp!,{rlist} - 0xE92D4000, // STMDB sp!,{rlist,lr} - 0xE8BD0000, // LDMIA sp!,{rlist} - 0xE8BD8000 // LDMIA sp!,{rlist,pc} - }; - *ainstr = subset[((tinstr & (1 << 11)) >> 10) | ((tinstr & (1 << 8)) >> 8)] // base - | (tinstr & 0x00FF); // mask8 - } - break; - - case 24: // STMIA - case 25: // LDMIA - if (tinstr & (1 << 11)) { - unsigned int base = 0xE8900000; - unsigned int rn = BITS(tinstr, 8, 10); - - // Writeback - if ((tinstr & (1 << rn)) == 0) - base |= (1 << 21); - - *ainstr = base // base (LDMIA) - | (rn << 16) // Rn - | (tinstr & 0x00FF); // Register list - } else { - *ainstr = 0xE8A00000 // base (STMIA) - | (BITS(tinstr, 8, 10) << 16) // Rn - | (tinstr & 0x00FF); // Register list - } - break; - - case 26: // Bcc - case 27: // Bcc/SWI - if ((tinstr & 0x0F00) == 0x0F00) { - // Format 17 : SWI - *ainstr = 0xEF000000; - // Breakpoint must be handled specially. - if ((tinstr & 0x00FF) == 0x18) - *ainstr |= ((tinstr & 0x00FF) << 16); - // New breakpoint value. See gdb/arm-tdep.c - else if ((tinstr & 0x00FF) == 0xFE) - *ainstr |= 0x180000; // base |= BKPT mask - else - *ainstr |= (tinstr & 0x00FF); - } else if ((tinstr & 0x0F00) != 0x0E00) - valid = ThumbDecodeStatus::BRANCH; - else // UNDEFINED : cc=1110(AL) uses different format - valid = ThumbDecodeStatus::UNDEFINED; - - break; - - case 28: // B - valid = ThumbDecodeStatus::BRANCH; - break; - - case 29: - if (tinstr & 0x1) - valid = ThumbDecodeStatus::UNDEFINED; - else - valid = ThumbDecodeStatus::BRANCH; - break; - - case 30: // BL instruction 1 - - // There is no single ARM instruction equivalent for this Thumb instruction. To keep the - // simulation simple (from the user perspective) we check if the following instruction is - // the second half of this BL, and if it is we simulate it immediately - - valid = ThumbDecodeStatus::BRANCH; - break; - - case 31: // BL instruction 2 - - // There is no single ARM instruction equivalent for this instruction. Also, it should only - // ever be matched with the fmt19 "BL instruction 1" instruction. However, we do allow the - // simulation of it on its own, with undefined results if r14 is not suitably initialised. - - valid = ThumbDecodeStatus::BRANCH; - break; - } - - *inst_size = 2; - - return valid; -} |