MIPS COP1X (and related) instructions, by Richard Sandiford. (b8aa4598) · Commits · SUMMER2020 / students / proj-2021291

target-mips/cpu.h

+11 −7

Original line number	Diff line number	Diff line
		@@ -417,7 +417,7 @@ struct CPUMIPSState {
		int user_mode_only; /* user mode only simulation */
		uint32_t hflags; /* CPU State */
		/* TMASK defines different execution modes */
		#define MIPS_HFLAG_TMASK 0x00FF
		#define MIPS_HFLAG_TMASK 0x01FF
		#define MIPS_HFLAG_MODE 0x0007 /* execution modes */
		/* The KSU flags must be the lowest bits in hflags. The flag order
		must be the same as defined for CP0 Status. This allows to use
		@@ -431,16 +431,20 @@ struct CPUMIPSState {
		#define MIPS_HFLAG_CP0 0x0010 /* CP0 enabled */
		#define MIPS_HFLAG_FPU 0x0020 /* FPU enabled */
		#define MIPS_HFLAG_F64 0x0040 /* 64-bit FPU enabled */
		#define MIPS_HFLAG_RE 0x0080 /* Reversed endianness */
		/* True if the MIPS IV COP1X instructions can be used. This also
		controls the non-COP1X instructions RECIP.S, RECIP.D, RSQRT.S
		and RSQRT.D. */
		#define MIPS_HFLAG_COP1X 0x0080 /* COP1X instructions enabled */
		#define MIPS_HFLAG_RE 0x0100 /* Reversed endianness */
		/* If translation is interrupted between the branch instruction and
		* the delay slot, record what type of branch it is so that we can
		* resume translation properly. It might be possible to reduce
		* this from three bits to two. */
		#define MIPS_HFLAG_BMASK 0x0700
		#define MIPS_HFLAG_B 0x0100 /* Unconditional branch */
		#define MIPS_HFLAG_BC 0x0200 /* Conditional branch */
		#define MIPS_HFLAG_BL 0x0300 /* Likely branch */
		#define MIPS_HFLAG_BR 0x0400 /* branch to register (can't link TB) */
		#define MIPS_HFLAG_BMASK 0x0e00
		#define MIPS_HFLAG_B 0x0200 /* Unconditional branch */
		#define MIPS_HFLAG_BC 0x0400 /* Conditional branch */
		#define MIPS_HFLAG_BL 0x0600 /* Likely branch */
		#define MIPS_HFLAG_BR 0x0800 /* branch to register (can't link TB) */
		target_ulong btarget; /* Jump / branch target */
		int bcond; /* Branch condition (if needed) */

target-mips/exec.h

+16 −2

Original line number	Diff line number	Diff line
		@@ -237,8 +237,8 @@ static always_inline int cpu_halted(CPUState *env)

		static always_inline void compute_hflags(CPUState *env)
		{
		env->hflags &= ~(MIPS_HFLAG_64 \| MIPS_HFLAG_CP0 \| MIPS_HFLAG_F64 \|
		MIPS_HFLAG_FPU \| MIPS_HFLAG_KSU);
		env->hflags &= ~(MIPS_HFLAG_COP1X \| MIPS_HFLAG_64 \| MIPS_HFLAG_CP0 \|
		MIPS_HFLAG_F64 \| MIPS_HFLAG_FPU \| MIPS_HFLAG_KSU);
		if (!(env->CP0_Status & (1 << CP0St_EXL)) &&
		!(env->CP0_Status & (1 << CP0St_ERL)) &&
		!(env->hflags & MIPS_HFLAG_DM)) {
		@@ -257,6 +257,20 @@ static always_inline void compute_hflags(CPUState *env)
		env->hflags \|= MIPS_HFLAG_FPU;
		if (env->CP0_Status & (1 << CP0St_FR))
		env->hflags \|= MIPS_HFLAG_F64;
		if (env->insn_flags & ISA_MIPS32R2) {
		if (env->fpu->fcr0 & FCR0_F64)
		env->hflags \|= MIPS_HFLAG_COP1X;
		} else if (env->insn_flags & ISA_MIPS32) {
		if (env->hflags & MIPS_HFLAG_64)
		env->hflags \|= MIPS_HFLAG_COP1X;
		} else if (env->insn_flags & ISA_MIPS4) {
		/* All supported MIPS IV CPUs use the XX (CU3) to enable
		and disable the MIPS IV extensions to the MIPS III ISA.
		Some other MIPS IV CPUs ignore the bit, so the check here
		would be too restrictive for them. */
		if (env->CP0_Status & (1 << CP0St_CU3))
		env->hflags \|= MIPS_HFLAG_COP1X;
		}
		}

		#endif /* !defined(__QEMU_MIPS_EXEC_H__) */

target-mips/translate.c

+47 −9

Original line number	Diff line number	Diff line
		@@ -794,9 +794,22 @@ static always_inline void check_cp1_enabled(DisasContext *ctx)
		generate_exception_err(ctx, EXCP_CpU, 1);
		}

		/* Verify that the processor is running with COP1X instructions enabled.
		This is associated with the nabla symbol in the MIPS32 and MIPS64
		opcode tables. */

		static always_inline void check_cop1x(DisasContext *ctx)
		{
		if (unlikely(!(ctx->hflags & MIPS_HFLAG_COP1X)))
		generate_exception(ctx, EXCP_RI);
		}

		/* Verify that the processor is running with 64-bit floating-point
		operations enabled. */

		static always_inline void check_cp1_64bitmode(DisasContext *ctx)
		{
		if (unlikely(!(ctx->hflags & MIPS_HFLAG_F64)))
		if (unlikely(~ctx->hflags & (MIPS_HFLAG_F64 \| MIPS_HFLAG_COP1X)))
		generate_exception(ctx, EXCP_RI);
		}

		@@ -5178,12 +5191,14 @@ static void gen_farith (DisasContext *ctx, uint32_t op1,
		opn = "movn.s";
		break;
		case FOP(21, 16):
		check_cop1x(ctx);
		GEN_LOAD_FREG_FTN(WT0, fs);
		gen_op_float_recip_s();
		GEN_STORE_FTN_FREG(fd, WT2);
		opn = "recip.s";
		break;
		case FOP(22, 16):
		check_cop1x(ctx);
		GEN_LOAD_FREG_FTN(WT0, fs);
		gen_op_float_rsqrt_s();
		GEN_STORE_FTN_FREG(fd, WT2);
		@@ -5266,7 +5281,7 @@ static void gen_farith (DisasContext *ctx, uint32_t op1,
		GEN_LOAD_FREG_FTN(WT0, fs);
		GEN_LOAD_FREG_FTN(WT1, ft);
		if (ctx->opcode & (1 << 6)) {
		check_cp1_64bitmode(ctx);
		check_cop1x(ctx);
		gen_cmpabs_s(func-48, cc);
		opn = condnames_abs[func-48];
		} else {
		@@ -5419,14 +5434,14 @@ static void gen_farith (DisasContext *ctx, uint32_t op1,
		opn = "movn.d";
		break;
		case FOP(21, 17):
		check_cp1_registers(ctx, fs \| fd);
		check_cp1_64bitmode(ctx);
		GEN_LOAD_FREG_FTN(DT0, fs);
		gen_op_float_recip_d();
		GEN_STORE_FTN_FREG(fd, DT2);
		opn = "recip.d";
		break;
		case FOP(22, 17):
		check_cp1_registers(ctx, fs \| fd);
		check_cp1_64bitmode(ctx);
		GEN_LOAD_FREG_FTN(DT0, fs);
		gen_op_float_rsqrt_d();
		GEN_STORE_FTN_FREG(fd, DT2);
		@@ -5481,7 +5496,8 @@ static void gen_farith (DisasContext *ctx, uint32_t op1,
		GEN_LOAD_FREG_FTN(DT0, fs);
		GEN_LOAD_FREG_FTN(DT1, ft);
		if (ctx->opcode & (1 << 6)) {
		check_cp1_64bitmode(ctx);
		check_cop1x(ctx);
		check_cp1_registers(ctx, fs \| ft);
		gen_cmpabs_d(func-48, cc);
		opn = condnames_abs[func-48];
		} else {
		@@ -5814,8 +5830,6 @@ static void gen_flt3_ldst (DisasContext *ctx, uint32_t opc,
		const char *opn = "extended float load/store";
		int store = 0;

		/* All of those work only on 64bit FPUs. */
		check_cp1_64bitmode(ctx);
		if (base == 0) {
		if (index == 0)
		gen_op_reset_T0();
		@@ -5832,33 +5846,41 @@ static void gen_flt3_ldst (DisasContext *ctx, uint32_t opc,
		memory access. */
		switch (opc) {
		case OPC_LWXC1:
		check_cop1x(ctx);
		op_ldst(lwc1);
		GEN_STORE_FTN_FREG(fd, WT0);
		opn = "lwxc1";
		break;
		case OPC_LDXC1:
		check_cop1x(ctx);
		check_cp1_registers(ctx, fd);
		op_ldst(ldc1);
		GEN_STORE_FTN_FREG(fd, DT0);
		opn = "ldxc1";
		break;
		case OPC_LUXC1:
		check_cp1_64bitmode(ctx);
		op_ldst(luxc1);
		GEN_STORE_FTN_FREG(fd, DT0);
		opn = "luxc1";
		break;
		case OPC_SWXC1:
		check_cop1x(ctx);
		GEN_LOAD_FREG_FTN(WT0, fs);
		op_ldst(swc1);
		opn = "swxc1";
		store = 1;
		break;
		case OPC_SDXC1:
		check_cop1x(ctx);
		check_cp1_registers(ctx, fs);
		GEN_LOAD_FREG_FTN(DT0, fs);
		op_ldst(sdc1);
		opn = "sdxc1";
		store = 1;
		break;
		case OPC_SUXC1:
		check_cp1_64bitmode(ctx);
		GEN_LOAD_FREG_FTN(DT0, fs);
		op_ldst(suxc1);
		opn = "suxc1";
		@@ -5878,10 +5900,9 @@ static void gen_flt3_arith (DisasContext *ctx, uint32_t opc,
		{
		const char *opn = "flt3_arith";

		/* All of those work only on 64bit FPUs. */
		check_cp1_64bitmode(ctx);
		switch (opc) {
		case OPC_ALNV_PS:
		check_cp1_64bitmode(ctx);
		GEN_LOAD_REG_T0(fr);
		GEN_LOAD_FREG_FTN(DT0, fs);
		GEN_LOAD_FREG_FTN(DT1, ft);
		@@ -5890,6 +5911,7 @@ static void gen_flt3_arith (DisasContext *ctx, uint32_t opc,
		opn = "alnv.ps";
		break;
		case OPC_MADD_S:
		check_cop1x(ctx);
		GEN_LOAD_FREG_FTN(WT0, fs);
		GEN_LOAD_FREG_FTN(WT1, ft);
		GEN_LOAD_FREG_FTN(WT2, fr);
		@@ -5898,6 +5920,8 @@ static void gen_flt3_arith (DisasContext *ctx, uint32_t opc,
		opn = "madd.s";
		break;
		case OPC_MADD_D:
		check_cop1x(ctx);
		check_cp1_registers(ctx, fd \| fs \| ft \| fr);
		GEN_LOAD_FREG_FTN(DT0, fs);
		GEN_LOAD_FREG_FTN(DT1, ft);
		GEN_LOAD_FREG_FTN(DT2, fr);
		@@ -5906,6 +5930,7 @@ static void gen_flt3_arith (DisasContext *ctx, uint32_t opc,
		opn = "madd.d";
		break;
		case OPC_MADD_PS:
		check_cp1_64bitmode(ctx);
		GEN_LOAD_FREG_FTN(WT0, fs);
		GEN_LOAD_FREG_FTN(WTH0, fs);
		GEN_LOAD_FREG_FTN(WT1, ft);
		@@ -5918,6 +5943,7 @@ static void gen_flt3_arith (DisasContext *ctx, uint32_t opc,
		opn = "madd.ps";
		break;
		case OPC_MSUB_S:
		check_cop1x(ctx);
		GEN_LOAD_FREG_FTN(WT0, fs);
		GEN_LOAD_FREG_FTN(WT1, ft);
		GEN_LOAD_FREG_FTN(WT2, fr);
		@@ -5926,6 +5952,8 @@ static void gen_flt3_arith (DisasContext *ctx, uint32_t opc,
		opn = "msub.s";
		break;
		case OPC_MSUB_D:
		check_cop1x(ctx);
		check_cp1_registers(ctx, fd \| fs \| ft \| fr);
		GEN_LOAD_FREG_FTN(DT0, fs);
		GEN_LOAD_FREG_FTN(DT1, ft);
		GEN_LOAD_FREG_FTN(DT2, fr);
		@@ -5934,6 +5962,7 @@ static void gen_flt3_arith (DisasContext *ctx, uint32_t opc,
		opn = "msub.d";
		break;
		case OPC_MSUB_PS:
		check_cp1_64bitmode(ctx);
		GEN_LOAD_FREG_FTN(WT0, fs);
		GEN_LOAD_FREG_FTN(WTH0, fs);
		GEN_LOAD_FREG_FTN(WT1, ft);
		@@ -5946,6 +5975,7 @@ static void gen_flt3_arith (DisasContext *ctx, uint32_t opc,
		opn = "msub.ps";
		break;
		case OPC_NMADD_S:
		check_cop1x(ctx);
		GEN_LOAD_FREG_FTN(WT0, fs);
		GEN_LOAD_FREG_FTN(WT1, ft);
		GEN_LOAD_FREG_FTN(WT2, fr);
		@@ -5954,6 +5984,8 @@ static void gen_flt3_arith (DisasContext *ctx, uint32_t opc,
		opn = "nmadd.s";
		break;
		case OPC_NMADD_D:
		check_cop1x(ctx);
		check_cp1_registers(ctx, fd \| fs \| ft \| fr);
		GEN_LOAD_FREG_FTN(DT0, fs);
		GEN_LOAD_FREG_FTN(DT1, ft);
		GEN_LOAD_FREG_FTN(DT2, fr);
		@@ -5962,6 +5994,7 @@ static void gen_flt3_arith (DisasContext *ctx, uint32_t opc,
		opn = "nmadd.d";
		break;
		case OPC_NMADD_PS:
		check_cp1_64bitmode(ctx);
		GEN_LOAD_FREG_FTN(WT0, fs);
		GEN_LOAD_FREG_FTN(WTH0, fs);
		GEN_LOAD_FREG_FTN(WT1, ft);
		@@ -5974,6 +6007,7 @@ static void gen_flt3_arith (DisasContext *ctx, uint32_t opc,
		opn = "nmadd.ps";
		break;
		case OPC_NMSUB_S:
		check_cop1x(ctx);
		GEN_LOAD_FREG_FTN(WT0, fs);
		GEN_LOAD_FREG_FTN(WT1, ft);
		GEN_LOAD_FREG_FTN(WT2, fr);
		@@ -5982,6 +6016,8 @@ static void gen_flt3_arith (DisasContext *ctx, uint32_t opc,
		opn = "nmsub.s";
		break;
		case OPC_NMSUB_D:
		check_cop1x(ctx);
		check_cp1_registers(ctx, fd \| fs \| ft \| fr);
		GEN_LOAD_FREG_FTN(DT0, fs);
		GEN_LOAD_FREG_FTN(DT1, ft);
		GEN_LOAD_FREG_FTN(DT2, fr);
		@@ -5990,6 +6026,7 @@ static void gen_flt3_arith (DisasContext *ctx, uint32_t opc,
		opn = "nmsub.d";
		break;
		case OPC_NMSUB_PS:
		check_cp1_64bitmode(ctx);
		GEN_LOAD_FREG_FTN(WT0, fs);
		GEN_LOAD_FREG_FTN(WTH0, fs);
		GEN_LOAD_FREG_FTN(WT1, ft);
		@@ -6465,6 +6502,7 @@ static void decode_opc (CPUState env, DisasContext ctx)
		#endif
		case OPC_BC1ANY2:
		case OPC_BC1ANY4:
		check_cop1x(ctx);
		check_insn(env, ctx, ASE_MIPS3D);
		/* fall through */
		case OPC_BC1: