feat(zicsr): add zicsr instructions + parser stubs

h/form/csr.h

@@ -0,0 +1,4 @@
+#pragma once
+#include "form/instructions.h"
+
+extern const struct formation zicsr[];

h/parse.h

@@ -26,5 +26,7 @@ arg_parser parse_jr;
 arg_parser parse_ftso;
 arg_parser parse_al;
 arg_parser parse_as;
+arg_parser parse_csr;
+arg_parser parse_csri;
 
 int parse_asm(const char *, struct sectionpos);

src/form/csr.c

@@ -0,0 +1,16 @@
+
+#include "form/csr.h"
+
+#include "form/generic.h"
+#include "parse.h"
+
+const struct formation zicsr[] = {
+	{ "csrrw", &form_itype, &parse_csr, { 4, OP_CSR, 0x1, 0 } },
+	{ "csrrs", &form_itype, &parse_csr, { 4, OP_CSR, 0x2, 0 } },
+	{ "csrrc", &form_itype, &parse_csr, { 4, OP_CSR, 0x3, 0 } },
+	{ "csrrwi", &form_itype, &parse_csri, { 4, OP_CSR, 0x5, 0 } },
+	{ "csrrsi", &form_itype, &parse_csri, { 4, OP_CSR, 0x6, 0 } },
+	{ "csrrci", &form_itype, &parse_csri, { 4, OP_CSR, 0x7, 0 } },
+
+	END_FORMATION
+};

src/parse.c

@@ -727,3 +727,13 @@ struct args parse_as(char *argstr)
 
 	return args;
 }
+
+struct args parse_csr(char *argstr)
+{
+
+}
+
+struct args parse_csri(char *argstr)
+{
+
+}