+// See LICENSE for license details.
+
#ifndef _RISCV_DECODE_H
#define _RISCV_DECODE_H
#define __STDC_LIMIT_MACROS
#include <stdint.h>
+#include <string.h>
+#include "pcr.h"
+#include "config.h"
+
typedef int int128_t __attribute__((mode(TI)));
typedef unsigned int uint128_t __attribute__((mode(TI)));
-#define support_64bit 1
typedef int64_t sreg_t;
typedef uint64_t reg_t;
-
-union freg_t
-{
- float sp;
- double dp;
- uint64_t bits;
-};
+typedef uint64_t freg_t;
const int OPCODE_BITS = 7;
-const int JTYPE_OPCODE_BITS = 5;
-const int GPR_BITS = 8*sizeof(reg_t);
-const int GPRID_BITS = 5;
-const int NGPR = 1 << GPRID_BITS;
+const int XPRID_BITS = 5;
+const int NXPR = 1 << XPRID_BITS;
const int FPR_BITS = 64;
const int FPRID_BITS = 5;
const int NFPR = 1 << FPRID_BITS;
const int IMM_BITS = 12;
-const int TARGET_BITS = 27;
-const int SHAMT_BITS = 6;
+const int IMMLO_BITS = 7;
+const int TARGET_BITS = 25;
const int FUNCT_BITS = 3;
-const int FFUNCT_BITS = 5;
+const int FUNCTR_BITS = 7;
+const int FFUNCT_BITS = 2;
+const int RM_BITS = 3;
const int BIGIMM_BITS = 20;
+const int BRANCH_ALIGN_BITS = 1;
+const int JUMP_ALIGN_BITS = 1;
+
+#define FP_RD_NE 0
+#define FP_RD_0 1
+#define FP_RD_DN 2
+#define FP_RD_UP 3
+#define FP_RD_NMM 4
-#define SR_ET 0x0000000000000001ULL
-#define SR_PS 0x0000000000000004ULL
-#define SR_S 0x0000000000000008ULL
-#define SR_EF 0x0000000000000010ULL
-#define SR_UX 0x0000000000000020ULL
-#define SR_KX 0x0000000000000040ULL
-#define SR_IM 0x000000000000FF00ULL
-#define SR_ZERO 0xFFFFFFFFFFFF0082ULL
+#define FSR_RD_SHIFT 5
+#define FSR_RD (0x7 << FSR_RD_SHIFT)
+
+#define FPEXC_NX 0x01
+#define FPEXC_UF 0x02
+#define FPEXC_OF 0x04
+#define FPEXC_DZ 0x08
+#define FPEXC_NV 0x10
+
+#define FSR_AEXC_SHIFT 0
+#define FSR_NVA (FPEXC_NV << FSR_AEXC_SHIFT)
+#define FSR_OFA (FPEXC_OF << FSR_AEXC_SHIFT)
+#define FSR_UFA (FPEXC_UF << FSR_AEXC_SHIFT)
+#define FSR_DZA (FPEXC_DZ << FSR_AEXC_SHIFT)
+#define FSR_NXA (FPEXC_NX << FSR_AEXC_SHIFT)
+#define FSR_AEXC (FSR_NVA | FSR_OFA | FSR_UFA | FSR_DZA | FSR_NXA)
+
+#define FSR_ZERO ~(FSR_RD | FSR_AEXC)
// note: bit fields are in little-endian order
struct itype_t
{
- unsigned imm : IMM_BITS;
+ unsigned opcode : OPCODE_BITS;
unsigned funct : FUNCT_BITS;
- unsigned rb : GPRID_BITS;
- unsigned ra : GPRID_BITS;
+ signed imm12 : IMM_BITS;
+ unsigned rs1 : XPRID_BITS;
+ unsigned rd : XPRID_BITS;
+};
+
+struct btype_t
+{
unsigned opcode : OPCODE_BITS;
+ unsigned funct : FUNCT_BITS;
+ unsigned immlo : IMMLO_BITS;
+ unsigned rs2 : XPRID_BITS;
+ unsigned rs1 : XPRID_BITS;
+ signed immhi : IMM_BITS-IMMLO_BITS;
};
struct jtype_t
{
- unsigned target : TARGET_BITS;
- unsigned jump_opcode : JTYPE_OPCODE_BITS;
+ unsigned jump_opcode : OPCODE_BITS;
+ signed target : TARGET_BITS;
};
struct rtype_t
{
- unsigned rc : GPRID_BITS;
- unsigned shamt : SHAMT_BITS;
- unsigned unused : 1;
- unsigned funct : FUNCT_BITS;
- unsigned rb : GPRID_BITS;
- unsigned ra : GPRID_BITS;
unsigned opcode : OPCODE_BITS;
+ unsigned funct : FUNCT_BITS;
+ unsigned functr : FUNCTR_BITS;
+ unsigned rs2 : XPRID_BITS;
+ unsigned rs1 : XPRID_BITS;
+ unsigned rd : XPRID_BITS;
};
-struct btype_t
+struct ltype_t
{
- unsigned bigimm : BIGIMM_BITS;
- unsigned rt : GPRID_BITS;
unsigned opcode : OPCODE_BITS;
+ unsigned bigimm : BIGIMM_BITS;
+ unsigned rd : XPRID_BITS;
};
struct ftype_t
{
- unsigned rc : FPRID_BITS;
- unsigned rd : FPRID_BITS;
- unsigned ffunct : FFUNCT_BITS;
- unsigned rb : FPRID_BITS;
- unsigned ra : FPRID_BITS;
unsigned opcode : OPCODE_BITS;
+ unsigned ffunct : FFUNCT_BITS;
+ unsigned rm : RM_BITS;
+ unsigned rs3 : FPRID_BITS;
+ unsigned rs2 : FPRID_BITS;
+ unsigned rs1 : FPRID_BITS;
+ unsigned rd : FPRID_BITS;
};
union insn_t
jtype_t jtype;
rtype_t rtype;
btype_t btype;
+ ltype_t ltype;
ftype_t ftype;
uint32_t bits;
};
+template <class T>
+class write_port_t
+{
+public:
+ write_port_t(T& _t) : t(_t) {}
+ T& operator = (const T& rhs)
+ {
+ return t = rhs;
+ }
+ operator T()
+ {
+ return t;
+ }
+private:
+ T& t;
+};
+template <class T, size_t N, bool zero_reg>
+class regfile_t
+{
+public:
+ void reset()
+ {
+ memset(data, 0, sizeof(data));
+ }
+ write_port_t<T> write_port(size_t i)
+ {
+ return write_port_t<T>(data[i]);
+ }
+ const T& operator [] (size_t i) const
+ {
+ if (zero_reg)
+ const_cast<T&>(data[0]) = 0;
+ return data[i];
+ }
+private:
+ T data[N];
+};
+
+#define throw_illegal_instruction \
+ ({ if (utmode) throw trap_vector_illegal_instruction; \
+ else throw trap_illegal_instruction; })
+
// helpful macros, etc
-#define RA R[insn.rtype.ra]
-#define RB R[insn.rtype.rb]
-#define RC R[insn.rtype.rc]
-#define FRA FR[insn.ftype.ra]
-#define FRB FR[insn.ftype.rb]
-#define FRC FR[insn.ftype.rc]
-#define FRD FR[insn.ftype.rd]
-#define BIGIMM insn.btype.bigimm
-#define IMM insn.itype.imm
-#define SIMM ((int32_t)((uint32_t)insn.itype.imm<<(32-IMM_BITS))>>(32-IMM_BITS))
-#define SHAMT insn.rtype.shamt
+#define RS1 XPR[insn.rtype.rs1]
+#define RS2 XPR[insn.rtype.rs2]
+#define RD XPR.write_port(insn.rtype.rd)
+#define RA XPR.write_port(1)
+#define FRS1 FPR[insn.ftype.rs1]
+#define FRS2 FPR[insn.ftype.rs2]
+#define FRS3 FPR[insn.ftype.rs3]
+#define FRD FPR.write_port(insn.ftype.rd)
+#define BIGIMM insn.ltype.bigimm
+#define SIMM insn.itype.imm12
+#define BIMM ((signed)insn.btype.immlo | (insn.btype.immhi << IMMLO_BITS))
+#define SHAMT (insn.itype.imm12 & 0x3F)
+#define SHAMTW (insn.itype.imm12 & 0x1F)
#define TARGET insn.jtype.target
-#define BRANCH_TARGET (npc + (SIMM*sizeof(insn_t)))
-#define JUMP_TARGET ((npc & ~((1<<TARGET_BITS)*sizeof(insn_t)-1)) + TARGET*sizeof(insn_t))
+#define BRANCH_TARGET (pc + (BIMM << BRANCH_ALIGN_BITS))
+#define JUMP_TARGET (pc + (TARGET << JUMP_ALIGN_BITS))
+#define ITYPE_EADDR sext_xprlen(RS1 + SIMM)
+#define BTYPE_EADDR sext_xprlen(RS1 + BIMM)
+#define RM ({ int rm = insn.ftype.rm; \
+ if(rm == 7) rm = (fsr & FSR_RD) >> FSR_RD_SHIFT; \
+ if(rm > 4) throw_illegal_instruction; \
+ rm; })
+
+#define xpr64 (xprlen == 64)
+
+#define require_supervisor if(unlikely(!(sr & SR_S))) throw trap_privileged_instruction
+#define require_xpr64 if(unlikely(!xpr64)) throw_illegal_instruction
+#define require_xpr32 if(unlikely(xpr64)) throw_illegal_instruction
+#ifndef RISCV_ENABLE_FPU
+# define require_fp throw trap_illegal_instruction
+#else
+# define require_fp if(unlikely(!(sr & SR_EF))) throw trap_fp_disabled
+#endif
+#ifndef RISCV_ENABLE_VEC
+# define require_vector throw trap_illegal_instruction
+#else
+# define require_vector \
+ ({ if(!(sr & SR_EV)) throw trap_vector_disabled; \
+ else if (!utmode && (vecbanks_count < 3)) throw trap_vector_bank; \
+ })
+#endif
+
+#define cmp_trunc(reg) (reg_t(reg) << (64-xprlen))
+#define set_fp_exceptions ({ set_fsr(fsr | \
+ (softfloat_exceptionFlags << FSR_AEXC_SHIFT)); \
+ softfloat_exceptionFlags = 0; })
-#define require_supervisor if(!(sr & SR_S)) throw trap_privileged_instruction
-#define require64 if(gprlen != 64) throw trap_illegal_instruction
-#define require_fp if(!(sr & SR_EF)) throw trap_fp_disabled
-#define cmp_trunc(reg) (reg_t(reg) << (64-gprlen))
+#define sext32(x) ((sreg_t)(int32_t)(x))
+#define zext32(x) ((reg_t)(uint32_t)(x))
+#define sext_xprlen(x) (((sreg_t)(x) << (64-xprlen)) >> (64-xprlen))
+#define zext_xprlen(x) (((reg_t)(x) << (64-xprlen)) >> (64-xprlen))
-static inline sreg_t sext32(int32_t arg)
+// RVC stuff
+
+#define INSN_IS_RVC(x) (((x) & 0x3) < 0x3)
+#define insn_length(x) (INSN_IS_RVC(x) ? 2 : 4)
+#define require_rvc if(!(sr & SR_EC)) throw_illegal_instruction
+
+#define CRD_REGNUM ((insn.bits >> 5) & 0x1f)
+#define CRD XPR.write_port(CRD_REGNUM)
+#define CRS1 XPR[(insn.bits >> 10) & 0x1f]
+#define CRS2 XPR[(insn.bits >> 5) & 0x1f]
+#define CIMM6 ((int32_t)((insn.bits >> 10) & 0x3f) << 26 >> 26)
+#define CIMM5U ((insn.bits >> 5) & 0x1f)
+#define CIMM5 ((int32_t)CIMM5U << 27 >> 27)
+#define CIMM10 ((int32_t)((insn.bits >> 5) & 0x3ff) << 22 >> 22)
+#define CBRANCH_TARGET (pc + (CIMM5 << BRANCH_ALIGN_BITS))
+#define CJUMP_TARGET (pc + (CIMM10 << JUMP_ALIGN_BITS))
+
+static const int rvc_rs1_regmap[8] = { 20, 21, 2, 3, 4, 5, 6, 7 };
+#define rvc_rd_regmap rvc_rs1_regmap
+#define rvc_rs2b_regmap rvc_rs1_regmap
+static const int rvc_rs2_regmap[8] = { 20, 21, 2, 3, 4, 5, 6, 0 };
+#define CRDS XPR.write_port(rvc_rd_regmap[(insn.bits >> 13) & 0x7])
+#define FCRDS FPR.write_port(rvc_rd_regmap[(insn.bits >> 13) & 0x7])
+#define CRS1S XPR[rvc_rs1_regmap[(insn.bits >> 10) & 0x7]]
+#define CRS2S XPR[rvc_rs2_regmap[(insn.bits >> 13) & 0x7]]
+#define CRS2BS XPR[rvc_rs2b_regmap[(insn.bits >> 5) & 0x7]]
+#define FCRS2S FPR[rvc_rs2_regmap[(insn.bits >> 13) & 0x7]]
+
+// vector stuff
+#define VL vl
+
+#define UT_RS1(idx) uts[idx]->XPR[insn.rtype.rs1]
+#define UT_RS2(idx) uts[idx]->XPR[insn.rtype.rs2]
+#define UT_RD(idx) uts[idx]->XPR.write_port(insn.rtype.rd)
+#define UT_RA(idx) uts[idx]->XPR.write_port(1)
+#define UT_FRS1(idx) uts[idx]->FPR[insn.ftype.rs1]
+#define UT_FRS2(idx) uts[idx]->FPR[insn.ftype.rs2]
+#define UT_FRS3(idx) uts[idx]->FPR[insn.ftype.rs3]
+#define UT_FRD(idx) uts[idx]->FPR.write_port(insn.ftype.rd)
+#define UT_RM(idx) ((insn.ftype.rm != 7) ? insn.ftype.rm : \
+ ((uts[idx]->fsr & FSR_RD) >> FSR_RD_SHIFT))
+
+#define UT_LOOP_START for (int i=0;i<VL; i++) {
+#define UT_LOOP_END }
+#define UT_LOOP_RS1 UT_RS1(i)
+#define UT_LOOP_RS2 UT_RS2(i)
+#define UT_LOOP_RD UT_RD(i)
+#define UT_LOOP_RA UT_RA(i)
+#define UT_LOOP_FRS1 UT_FRS1(i)
+#define UT_LOOP_FRS2 UT_FRS2(i)
+#define UT_LOOP_FRS3 UT_FRS3(i)
+#define UT_LOOP_FRD UT_FRD(i)
+#define UT_LOOP_RM UT_RM(i)
+
+#define VEC_LOAD(dst, func, inc) \
+ reg_t addr = RS1; \
+ UT_LOOP_START \
+ UT_LOOP_##dst = mmu.func(addr); \
+ addr += inc; \
+ UT_LOOP_END
+
+#define VEC_STORE(src, func, inc) \
+ reg_t addr = RS1; \
+ UT_LOOP_START \
+ mmu.func(addr, UT_LOOP_##src); \
+ addr += inc; \
+ UT_LOOP_END
+
+enum vt_command_t
{
- return arg;
-}
+ vt_command_stop,
+};
#endif
projects / riscv-isa-sim.git / blobdiff