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rvcpp: Add Zcb support. Also fix -Wparentheses as sometimes it does find things

This commit is contained in:
Luke Wren 2024-06-02 10:15:57 +01:00
parent 3a747e1dde
commit cbc2172930
2 changed files with 80 additions and 7 deletions
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7
test/sim/rvcpp/Makefile
View File

@ -2,10 +2,13 @@ SRCS=$(wildcard *.cpp)
EXECUTABLE:=rvcpp
.SUFFIXES:
.PHONY: all clean
.PHONY: all clean tb
all:
g++ -std=c++17 -O3 -Wall -Wno-parentheses -I include $(SRCS) -o $(EXECUTABLE)
g++ -std=c++17 -O3 -Wall -I include $(SRCS) -o $(EXECUTABLE)
# To match tb_cxxrtl/Makefile:
tb: all
clean:
rm -f $(EXECUTABLE)

80
test/sim/rvcpp/rv_core.cpp
View File

@ -6,10 +6,13 @@
// Use unsigned arithmetic everywhere, with explicit sign extension as required.
static inline ux_t sext(ux_t bits, int sign_bit) {
if (sign_bit >= XLEN - 1)
if (sign_bit >= XLEN - 1) {
return bits;
else
return (bits & (1u << sign_bit + 1) - 1) - ((bits & 1u << sign_bit) << 1);
} else {
ux_t mask_sign = 1u << sign_bit;
ux_t mask_below_sign = mask_sign - 1;
return (bits & mask_below_sign) - (bits & mask_sign);
}
}
// Inclusive msb:lsb style, like Verilog (and like the ISA manual)
@ -191,9 +194,9 @@ void RVCore::step(bool trace) {
sdx_t mul_op_a = rs1;
sdx_t mul_op_b = rs2;
if (funct3 != 0b011)
mul_op_a -= (mul_op_a & (1 << XLEN - 1)) << 1;
mul_op_a -= (mul_op_a & (1 << (XLEN - 1))) << 1;
if (funct3 < 0b010)
mul_op_b -= (mul_op_b & (1 << XLEN - 1)) << 1;
mul_op_b -= (mul_op_b & (1 << (XLEN - 1))) << 1;
sdx_t mul_result = mul_op_a * mul_op_b;
if (funct3 == 0b000)
rd_wdata = mul_result;
@ -650,6 +653,54 @@ void RVCore::step(bool trace) {
if (!w32(addr, regs[c_rs2_s(instr)])) {
exception_cause = XCAUSE_STORE_FAULT;
}
} else if (RVOPC_MATCH(instr, C_LBU)) {
// Zcb:
regnum_rd = c_rs2_s(instr);
uint32_t addr = regs[c_rs1_s(instr)]
+ (GETBIT(instr, 6) << 0)
+ (GETBIT(instr, 5) << 1);
rd_wdata = r8(addr);
if (!rd_wdata) {
exception_cause = XCAUSE_LOAD_FAULT;
}
} else if (RVOPC_MATCH(instr, C_LHU)) {
regnum_rd = c_rs2_s(instr);
uint32_t addr = regs[c_rs1_s(instr)] + (GETBIT(instr, 5) << 1);
if (addr & 0x1u) {
exception_cause = XCAUSE_LOAD_ALIGN;
} else {
rd_wdata = r16(addr);
if (!rd_wdata) {
exception_cause = XCAUSE_LOAD_FAULT;
}
}
} else if (RVOPC_MATCH(instr, C_LH)) {
regnum_rd = c_rs2_s(instr);
uint32_t addr = regs[c_rs1_s(instr)] + (GETBIT(instr, 5) << 1);
if (addr & 0x1u) {
exception_cause = XCAUSE_LOAD_ALIGN;
} else {
rd_wdata = r16(addr);
if (rd_wdata) {
rd_wdata = sext(*rd_wdata, 15);
} else {
exception_cause = XCAUSE_LOAD_FAULT;
}
}
} else if (RVOPC_MATCH(instr, C_SB)) {
uint32_t addr = regs[c_rs1_s(instr)]
+ (GETBIT(instr, 6) << 0)
+ (GETBIT(instr, 5) << 1);
if (!w8(addr, regs[c_rs2_s(instr)])) {
exception_cause = XCAUSE_STORE_FAULT;
}
} else if (RVOPC_MATCH(instr, C_SH)) {
uint32_t addr = regs[c_rs1_s(instr)] + (GETBIT(instr, 5) << 1);
if (addr & 0x1u) {
exception_cause = XCAUSE_LOAD_ALIGN;
} else if (!w16(addr, regs[c_rs2_s(instr)])) {
exception_cause = XCAUSE_STORE_FAULT;
}
} else {
exception_cause = XCAUSE_INSTR_ILLEGAL;
}
@ -710,6 +761,25 @@ void RVCore::step(bool trace) {
if (regs[c_rs1_s(instr)] != 0) {
pc_wdata = pc + imm_cb(instr);
}
} else if (RVOPC_MATCH(instr, C_ZEXT_B)) {
// Zcb:
regnum_rd = c_rs1_s(instr);
rd_wdata = regs[regnum_rd] & 0xffu;
} else if (RVOPC_MATCH(instr, C_SEXT_B)) {
regnum_rd = c_rs1_s(instr);
rd_wdata = sext(regs[regnum_rd], 7);
} else if (RVOPC_MATCH(instr, C_ZEXT_H)) {
regnum_rd = c_rs1_s(instr);
rd_wdata = regs[regnum_rd] & 0xffffu;
} else if (RVOPC_MATCH(instr, C_SEXT_H)) {
regnum_rd = c_rs1_s(instr);
rd_wdata = sext(regs[regnum_rd], 15);
} else if (RVOPC_MATCH(instr, C_NOT)) {
regnum_rd = c_rs1_s(instr);
rd_wdata = ~regs[regnum_rd];
} else if (RVOPC_MATCH(instr, C_MUL)) {
regnum_rd = c_rs1_s(instr);
rd_wdata = regs[c_rs1_s(instr)] * regs[c_rs2_s(instr)];
} else {
exception_cause = XCAUSE_INSTR_ILLEGAL;
}