From ea4ca3c22646f5826e4adbfa006b564a5d38da8f Mon Sep 17 00:00:00 2001 From: Yongbok Kim Date: Thu, 2 Aug 2018 16:16:06 +0200 Subject: [PATCH] target/mips: Add emulation of nanoMIPS 16-bit arithmetic instructions Add emulation of nanoMIPS 16-bit arithmetic instructions. Reviewed-by: Richard Henderson Signed-off-by: Yongbok Kim Signed-off-by: Aleksandar Markovic Signed-off-by: Stefan Markovic --- target/mips/translate.c | 142 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 142 insertions(+) diff --git a/target/mips/translate.c b/target/mips/translate.c index ab982cf6d6..261680e642 100644 --- a/target/mips/translate.c +++ b/target/mips/translate.c @@ -16603,9 +16603,151 @@ enum { #define NANOMIPS_EXTRACT_RD5(op) ((op >> 5) & 0x1f) #define NANOMIPS_EXTRACT_RS5(op) (op & 0x1f) +/* Implement nanoMIPS pseudocode decode_gpr(encoded_gpr, 'gpr3'). */ +static inline int decode_gpr_gpr3(int r) +{ + static const int map[] = { 16, 17, 18, 19, 4, 5, 6, 7 }; + + return map[r & 0x7]; +} + +/* Implement nanoMIPS pseudocode decode_gpr(encoded_gpr, 'gpr4'). */ +static inline int decode_gpr_gpr4(int r) +{ + static const int map[] = { 8, 9, 10, 11, 4, 5, 6, 7, + 16, 17, 18, 19, 20, 21, 22, 23 }; + + return map[r & 0xf]; +} + static int decode_nanomips_opc(CPUMIPSState *env, DisasContext *ctx) { + uint32_t op; + int rt = decode_gpr_gpr3(NANOMIPS_EXTRACT_RD(ctx->opcode)); + int rs = decode_gpr_gpr3(NANOMIPS_EXTRACT_RS(ctx->opcode)); + int rd = decode_gpr_gpr3(NANOMIPS_EXTRACT_RS1(ctx->opcode)); + int imm; + + /* make sure instructions are on a halfword boundary */ + if (ctx->base.pc_next & 0x1) { + TCGv tmp = tcg_const_tl(ctx->base.pc_next); + tcg_gen_st_tl(tmp, cpu_env, offsetof(CPUMIPSState, CP0_BadVAddr)); + tcg_temp_free(tmp); + generate_exception_end(ctx, EXCP_AdEL); + return 2; + } + + op = extract32(ctx->opcode, 10, 6); + switch (op) { + case NM_P16_MV: + break; + case NM_P16_SHIFT: + break; + case NM_P16C: + break; + case NM_P16_A1: + switch (extract32(ctx->opcode, 6, 1)) { + case NM_ADDIUR1SP: + imm = extract32(ctx->opcode, 0, 6) << 2; + gen_arith_imm(ctx, OPC_ADDIU, rt, 29, imm); + break; + default: + generate_exception_end(ctx, EXCP_RI); + break; + } + break; + case NM_P16_A2: + switch (extract32(ctx->opcode, 3, 1)) { + case NM_ADDIUR2: + imm = extract32(ctx->opcode, 0, 3) << 2; + gen_arith_imm(ctx, OPC_ADDIU, rt, rs, imm); + break; + case NM_P_ADDIURS5: + rt = extract32(ctx->opcode, 5, 5); + if (rt != 0) { + /* imm = sign_extend(s[3] . s[2:0] , from_nbits = 4) */ + imm = (sextract32(ctx->opcode, 4, 1) << 3) | + (extract32(ctx->opcode, 0, 3)); + gen_arith_imm(ctx, OPC_ADDIU, rt, rt, imm); + } + break; + } + break; + case NM_P16_ADDU: + switch (ctx->opcode & 0x1) { + case NM_ADDU16: + gen_arith(ctx, OPC_ADDU, rd, rs, rt); + break; + case NM_SUBU16: + gen_arith(ctx, OPC_SUBU, rd, rs, rt); + break; + } + break; + case NM_P16_4X4: + rt = (extract32(ctx->opcode, 9, 1) << 3) | + extract32(ctx->opcode, 5, 3); + rs = (extract32(ctx->opcode, 4, 1) << 3) | + extract32(ctx->opcode, 0, 3); + rt = decode_gpr_gpr4(rt); + rs = decode_gpr_gpr4(rs); + switch ((extract32(ctx->opcode, 7, 2) & 0x2) | + (extract32(ctx->opcode, 3, 1))) { + case NM_ADDU4X4: + gen_arith(ctx, OPC_ADDU, rt, rs, rt); + break; + case NM_MUL4X4: + gen_r6_muldiv(ctx, R6_OPC_MUL, rt, rs, rt); + break; + default: + generate_exception_end(ctx, EXCP_RI); + break; + } + break; + case NM_LI16: + break; + case NM_ANDI16: + break; + case NM_P16_LB: + break; + case NM_P16_LH: + break; + case NM_LW16: + break; + case NM_LWSP16: + break; + case NM_LW4X4: + break; + case NM_SW4X4: + break; + case NM_LWGP16: + break; + case NM_SWSP16: + break; + case NM_SW16: + break; + case NM_SWGP16: + break; + case NM_BC16: + break; + case NM_BALC16: + break; + case NM_BEQZC16: + break; + case NM_BNEZC16: + break; + case NM_P16_BR: + break; + case NM_P16_SR: + break; + case NM_MOVEP: + break; + case NM_MOVEPREV: + break; + default: + break; + } + return 2; } -- 2.11.0