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[187.189.51.144]) by smtp.gmail.com with ESMTPSA id d84sm2070324qke.53.2021.03.11.06.40.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Mar 2021 06:40:26 -0800 (PST) From: Richard Henderson To: qemu-devel@nongnu.org Subject: [PATCH v5 21/57] tcg/tci: Implement the disassembler properly Date: Thu, 11 Mar 2021 08:39:22 -0600 Message-Id: <20210311143958.562625-22-richard.henderson@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210311143958.562625-1-richard.henderson@linaro.org> References: <20210311143958.562625-1-richard.henderson@linaro.org> MIME-Version: 1.0 Received-SPF: pass client-ip=2607:f8b0:4864:20::82b; envelope-from=richard.henderson@linaro.org; helo=mail-qt1-x82b.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: sw@weilnetz.de, alex.bennee@linaro.org, f4bug@amsat.org Errors-To: qemu-devel-bounces+patch=linaro.org@nongnu.org Sender: "Qemu-devel" Actually print arguments as opposed to simply the opcodes and, uselessly, the argument counts. Reuse all of the helpers developed as part of the interpreter. Signed-off-by: Richard Henderson --- meson.build | 2 +- include/tcg/tcg-opc.h | 2 - disas/tci.c | 61 --------- tcg/tci.c | 283 ++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 284 insertions(+), 64 deletions(-) delete mode 100644 disas/tci.c -- 2.25.1 Reviewed-by: Philippe Mathieu-Daudé diff --git a/meson.build b/meson.build index adeec153d9..fda86ab8ce 100644 --- a/meson.build +++ b/meson.build @@ -1943,7 +1943,7 @@ specific_ss.add(when: 'CONFIG_TCG', if_true: files( 'tcg/tcg-op.c', 'tcg/tcg.c', )) -specific_ss.add(when: 'CONFIG_TCG_INTERPRETER', if_true: files('disas/tci.c', 'tcg/tci.c')) +specific_ss.add(when: 'CONFIG_TCG_INTERPRETER', if_true: files('tcg/tci.c')) subdir('backends') subdir('disas') diff --git a/include/tcg/tcg-opc.h b/include/tcg/tcg-opc.h index 900984c005..bbb0884af8 100644 --- a/include/tcg/tcg-opc.h +++ b/include/tcg/tcg-opc.h @@ -278,10 +278,8 @@ DEF(last_generic, 0, 0, 0, TCG_OPF_NOT_PRESENT) #ifdef TCG_TARGET_INTERPRETER /* These opcodes are only for use between the tci generator and interpreter. */ DEF(tci_movi_i32, 1, 0, 1, TCG_OPF_NOT_PRESENT) -#if TCG_TARGET_REG_BITS == 64 DEF(tci_movi_i64, 1, 0, 1, TCG_OPF_64BIT | TCG_OPF_NOT_PRESENT) #endif -#endif #undef TLADDR_ARGS #undef DATA64_ARGS diff --git a/disas/tci.c b/disas/tci.c deleted file mode 100644 index f1d6c6b469..0000000000 --- a/disas/tci.c +++ /dev/null @@ -1,61 +0,0 @@ -/* - * Tiny Code Interpreter for QEMU - disassembler - * - * Copyright (c) 2011 Stefan Weil - * - * This program 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 of the License, or - * (at your option) any later version. - * - * This program 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. If not, see . - */ - -#include "qemu/osdep.h" -#include "qemu-common.h" -#include "disas/dis-asm.h" -#include "tcg/tcg.h" - -/* Disassemble TCI bytecode. */ -int print_insn_tci(bfd_vma addr, disassemble_info *info) -{ - int length; - uint8_t byte; - int status; - TCGOpcode op; - - status = info->read_memory_func(addr, &byte, 1, info); - if (status != 0) { - info->memory_error_func(status, addr, info); - return -1; - } - op = byte; - - addr++; - status = info->read_memory_func(addr, &byte, 1, info); - if (status != 0) { - info->memory_error_func(status, addr, info); - return -1; - } - length = byte; - - if (op >= tcg_op_defs_max) { - info->fprintf_func(info->stream, "illegal opcode %d", op); - } else { - const TCGOpDef *def = &tcg_op_defs[op]; - int nb_oargs = def->nb_oargs; - int nb_iargs = def->nb_iargs; - int nb_cargs = def->nb_cargs; - /* TODO: Improve disassembler output. */ - info->fprintf_func(info->stream, "%s\to=%d i=%d c=%d", - def->name, nb_oargs, nb_iargs, nb_cargs); - } - - return length; -} diff --git a/tcg/tci.c b/tcg/tci.c index 6b63beea28..41d73edc3a 100644 --- a/tcg/tci.c +++ b/tcg/tci.c @@ -1059,3 +1059,286 @@ uintptr_t QEMU_DISABLE_CFI tcg_qemu_tb_exec(CPUArchState *env, } } } + +/* + * Disassembler that matches the interpreter + */ + +static const char *str_r(TCGReg r) +{ + static const char regs[TCG_TARGET_NB_REGS][4] = { + "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", + "r8", "r9", "r10", "r11", "r12", "r13", "env", "sp" + }; + + QEMU_BUILD_BUG_ON(TCG_AREG0 != TCG_REG_R14); + QEMU_BUILD_BUG_ON(TCG_REG_CALL_STACK != TCG_REG_R15); + + assert((unsigned)r < TCG_TARGET_NB_REGS); + return regs[r]; +} + +static const char *str_c(TCGCond c) +{ + static const char cond[16][8] = { + [TCG_COND_NEVER] = "never", + [TCG_COND_ALWAYS] = "always", + [TCG_COND_EQ] = "eq", + [TCG_COND_NE] = "ne", + [TCG_COND_LT] = "lt", + [TCG_COND_GE] = "ge", + [TCG_COND_LE] = "le", + [TCG_COND_GT] = "gt", + [TCG_COND_LTU] = "ltu", + [TCG_COND_GEU] = "geu", + [TCG_COND_LEU] = "leu", + [TCG_COND_GTU] = "gtu", + }; + + assert((unsigned)c < ARRAY_SIZE(cond)); + assert(cond[c][0] != 0); + return cond[c]; +} + +/* Disassemble TCI bytecode. */ +int print_insn_tci(bfd_vma addr, disassemble_info *info) +{ + uint8_t buf[256]; + int length, status; + const TCGOpDef *def; + const char *op_name; + TCGOpcode op; + TCGReg r0, r1, r2, r3; +#if TCG_TARGET_REG_BITS == 32 + TCGReg r4, r5; +#endif + tcg_target_ulong i1; + int32_t s2; + TCGCond c; + TCGMemOpIdx oi; + uint8_t pos, len; + void *ptr; + const uint8_t *tb_ptr; + + status = info->read_memory_func(addr, buf, 2, info); + if (status != 0) { + info->memory_error_func(status, addr, info); + return -1; + } + op = buf[0]; + length = buf[1]; + + if (length < 2) { + info->fprintf_func(info->stream, "invalid length %d", length); + return 1; + } + + status = info->read_memory_func(addr + 2, buf + 2, length - 2, info); + if (status != 0) { + info->memory_error_func(status, addr + 2, info); + return -1; + } + + def = &tcg_op_defs[op]; + op_name = def->name; + tb_ptr = buf + 2; + + switch (op) { + case INDEX_op_br: + case INDEX_op_call: + case INDEX_op_exit_tb: + case INDEX_op_goto_tb: + tci_args_l(&tb_ptr, &ptr); + info->fprintf_func(info->stream, "%-12s %p", op_name, ptr); + break; + + case INDEX_op_brcond_i32: + case INDEX_op_brcond_i64: + tci_args_rrcl(&tb_ptr, &r0, &r1, &c, &ptr); + info->fprintf_func(info->stream, "%-12s %s,%s,%s,%p", + op_name, str_r(r0), str_r(r1), str_c(c), ptr); + break; + + case INDEX_op_setcond_i32: + case INDEX_op_setcond_i64: + tci_args_rrrc(&tb_ptr, &r0, &r1, &r2, &c); + info->fprintf_func(info->stream, "%-12s %s,%s,%s,%s", + op_name, str_r(r0), str_r(r1), str_r(r2), str_c(c)); + break; + + case INDEX_op_tci_movi_i32: + tci_args_ri(&tb_ptr, &r0, &i1); + info->fprintf_func(info->stream, "%-12s %s,0x%" TCG_PRIlx "", + op_name, str_r(r0), i1); + break; + +#if TCG_TARGET_REG_BITS == 64 + case INDEX_op_tci_movi_i64: + tci_args_rI(&tb_ptr, &r0, &i1); + info->fprintf_func(info->stream, "%-12s %s,0x%" TCG_PRIlx "", + op_name, str_r(r0), i1); + break; +#endif + + case INDEX_op_ld8u_i32: + case INDEX_op_ld8u_i64: + case INDEX_op_ld8s_i32: + case INDEX_op_ld8s_i64: + case INDEX_op_ld16u_i32: + case INDEX_op_ld16u_i64: + case INDEX_op_ld16s_i32: + case INDEX_op_ld16s_i64: + case INDEX_op_ld32u_i64: + case INDEX_op_ld32s_i64: + case INDEX_op_ld_i32: + case INDEX_op_ld_i64: + case INDEX_op_st8_i32: + case INDEX_op_st8_i64: + case INDEX_op_st16_i32: + case INDEX_op_st16_i64: + case INDEX_op_st32_i64: + case INDEX_op_st_i32: + case INDEX_op_st_i64: + tci_args_rrs(&tb_ptr, &r0, &r1, &s2); + info->fprintf_func(info->stream, "%-12s %s,%s,%d", + op_name, str_r(r0), str_r(r1), s2); + break; + + case INDEX_op_mov_i32: + case INDEX_op_mov_i64: + case INDEX_op_ext8s_i32: + case INDEX_op_ext8s_i64: + case INDEX_op_ext8u_i32: + case INDEX_op_ext8u_i64: + case INDEX_op_ext16s_i32: + case INDEX_op_ext16s_i64: + case INDEX_op_ext16u_i32: + case INDEX_op_ext32s_i64: + case INDEX_op_ext32u_i64: + case INDEX_op_ext_i32_i64: + case INDEX_op_extu_i32_i64: + case INDEX_op_bswap16_i32: + case INDEX_op_bswap16_i64: + case INDEX_op_bswap32_i32: + case INDEX_op_bswap32_i64: + case INDEX_op_bswap64_i64: + case INDEX_op_not_i32: + case INDEX_op_not_i64: + case INDEX_op_neg_i32: + case INDEX_op_neg_i64: + tci_args_rr(&tb_ptr, &r0, &r1); + info->fprintf_func(info->stream, "%-12s %s,%s", + op_name, str_r(r0), str_r(r1)); + break; + + case INDEX_op_add_i32: + case INDEX_op_add_i64: + case INDEX_op_sub_i32: + case INDEX_op_sub_i64: + case INDEX_op_mul_i32: + case INDEX_op_mul_i64: + case INDEX_op_and_i32: + case INDEX_op_and_i64: + case INDEX_op_or_i32: + case INDEX_op_or_i64: + case INDEX_op_xor_i32: + case INDEX_op_xor_i64: + case INDEX_op_div_i32: + case INDEX_op_div_i64: + case INDEX_op_rem_i32: + case INDEX_op_rem_i64: + case INDEX_op_divu_i32: + case INDEX_op_divu_i64: + case INDEX_op_remu_i32: + case INDEX_op_remu_i64: + case INDEX_op_shl_i32: + case INDEX_op_shl_i64: + case INDEX_op_shr_i32: + case INDEX_op_shr_i64: + case INDEX_op_sar_i32: + case INDEX_op_sar_i64: + case INDEX_op_rotl_i32: + case INDEX_op_rotl_i64: + case INDEX_op_rotr_i32: + case INDEX_op_rotr_i64: + tci_args_rrr(&tb_ptr, &r0, &r1, &r2); + info->fprintf_func(info->stream, "%-12s %s,%s,%s", + op_name, str_r(r0), str_r(r1), str_r(r2)); + break; + + case INDEX_op_deposit_i32: + case INDEX_op_deposit_i64: + tci_args_rrrbb(&tb_ptr, &r0, &r1, &r2, &pos, &len); + info->fprintf_func(info->stream, "%-12s %s,%s,%s,%d,%d", + op_name, str_r(r0), str_r(r1), str_r(r2), pos, len); + break; + +#if TCG_TARGET_REG_BITS == 32 + case INDEX_op_setcond2_i32: + tci_args_rrrrrc(&tb_ptr, &r0, &r1, &r2, &r3, &r4, &c); + info->fprintf_func(info->stream, "%-12s %s,%s,%s,%s,%s,%s", + op_name, str_r(r0), str_r(r1), str_r(r2), + str_r(r3), str_r(r4), str_c(c)); + break; + + case INDEX_op_brcond2_i32: + tci_args_rrrrcl(&tb_ptr, &r0, &r1, &r2, &r3, &c, &ptr); + info->fprintf_func(info->stream, "%-12s %s,%s,%s,%s,%s,%p", + op_name, str_r(r0), str_r(r1), + str_r(r2), str_r(r3), str_c(c), ptr); + break; + + case INDEX_op_mulu2_i32: + tci_args_rrrr(&tb_ptr, &r0, &r1, &r2, &r3); + info->fprintf_func(info->stream, "%-12s %s,%s,%s,%s", + op_name, str_r(r0), str_r(r1), + str_r(r2), str_r(r3)); + break; + + case INDEX_op_add2_i32: + case INDEX_op_sub2_i32: + tci_args_rrrrrr(&tb_ptr, &r0, &r1, &r2, &r3, &r4, &r5); + info->fprintf_func(info->stream, "%-12s %s,%s,%s,%s,%s,%s", + op_name, str_r(r0), str_r(r1), str_r(r2), + str_r(r3), str_r(r4), str_r(r5)); + break; +#endif + + case INDEX_op_qemu_ld_i64: + case INDEX_op_qemu_st_i64: + len = DIV_ROUND_UP(64, TCG_TARGET_REG_BITS); + goto do_qemu_ldst; + case INDEX_op_qemu_ld_i32: + case INDEX_op_qemu_st_i32: + len = 1; + do_qemu_ldst: + len += DIV_ROUND_UP(TARGET_LONG_BITS, TCG_TARGET_REG_BITS); + switch (len) { + case 2: + tci_args_rrm(&tb_ptr, &r0, &r1, &oi); + info->fprintf_func(info->stream, "%-12s %s,%s,%x", + op_name, str_r(r0), str_r(r1), oi); + break; + case 3: + tci_args_rrrm(&tb_ptr, &r0, &r1, &r2, &oi); + info->fprintf_func(info->stream, "%-12s %s,%s,%s,%x", + op_name, str_r(r0), str_r(r1), str_r(r2), oi); + break; + case 4: + tci_args_rrrrm(&tb_ptr, &r0, &r1, &r2, &r3, &oi); + info->fprintf_func(info->stream, "%-12s %s,%s,%s,%s,%x", + op_name, str_r(r0), str_r(r1), + str_r(r2), str_r(r3), oi); + break; + default: + g_assert_not_reached(); + } + break; + + default: + info->fprintf_func(info->stream, "illegal opcode %d", op); + break; + } + + return length; +}