rvv: add simple instruction parsing tool

the tool can parse the instruction name from spike debug log to help
dsp kernel designer check what instructions have been used

Signed-off-by: Jerry Shih <bignose1007@gmail.com>

riscv/disasm.h

@@ -40,6 +40,11 @@ class disasm_insn_t
     return (insn.bits() & mask) == match;
   }
 
+  const char* get_name() const
+  {
+    return name;
+  }
+
   std::string to_string(insn_t insn) const
   {
     std::stringstream s;
@@ -83,12 +88,15 @@ class disassembler_t
  public:
   disassembler_t(int xlen);
   ~disassembler_t();
+
   std::string disassemble(insn_t insn) const;
+  const disasm_insn_t* lookup(insn_t insn) const;
+
   void add_insn(disasm_insn_t* insn);
+
  private:
   static const int HASH_SIZE = 256;
   std::vector<const disasm_insn_t*> chain[HASH_SIZE+1];
-  const disasm_insn_t* lookup(insn_t insn) const;
 };
 
 #endif

spike_main/spike-log-parser.cc

@@ -0,0 +1,60 @@
+// See LICENSE for license details.
+
+// This little program finds occurrences of strings like
+//   core   0: 0x000000008000c36c (0xfe843783) ld      a5, -24(s0)
+// in its inputs, then output the RISC-V instruction with the disassembly
+// enclosed hexadecimal number.
+
+#include <iostream>
+#include <string>
+#include <cstdint>
+#include <regex>
+#include "fesvr/option_parser.h"
+
+#include "disasm.h"
+#include "extension.h"
+
+using namespace std;
+
+int main(int argc, char** argv)
+{
+  string s;
+  const char* isa = DEFAULT_ISA;
+
+  std::function<extension_t*()> extension;
+  option_parser_t parser;
+  parser.option(0, "extension", 1, [&](const char* s){extension = find_extension(s);});
+  parser.option(0, "isa", 1, [&](const char* s){isa = s;});
+  parser.parse(argv);
+
+  processor_t p(isa, DEFAULT_VARCH, 0, 0);
+  if (extension) {
+    p.register_extension(extension());
+  }
+
+  std::regex reg("^core\\s+\\d+:\\s+0x[0-9a-f]+\\s+\\(0x([0-9a-f]+)\\)", std::regex_constants::icase);
+  std::smatch m;
+  std::ssub_match sm ;
+
+  while (getline(cin,s)){
+    if (regex_search(s, m, reg)){
+      // the opcode string
+      string op = m[1].str();
+      uint32_t bit_num = op.size() * 4;
+      uint64_t opcode = strtoull(op.c_str(), nullptr, 16);
+
+      if (bit_num<64){
+          opcode = opcode << (64-bit_num) >> (64-bit_num);
+      }
+
+      const disasm_insn_t* disasm = p.get_disassembler()->lookup(opcode);
+      if (disasm) {
+          cout << disasm->get_name() << '\n';
+      } else {
+          cout << "unknown_op\n";
+      }
+    }
+  }
+
+  return 0;
+}

spike_main/spike_main.mk.in

@@ -6,6 +6,7 @@ spike_main_subproject_deps = \
 spike_main_install_prog_srcs = \
 	spike.cc \
 	spike-dasm.cc \
+	spike-log-parser.cc \
 	xspike.cc \
 	termios-xspike.cc \