rvemu

commit 4f6ec22e8cb9e98e786ab20e830f52cf1042e019
parent feb123c9c5c8b0cdcee6cb11bcf14344a44adf98
Author: Michail Konstantinos Dimopoulos <mk@mcdim.xyz>
Date:   Mon,  7 Sep 2026 10:59:35 +0300

Optional readline in dbg, new makefile

Diffstat:
M
Makefile
 | 
30
+++++++++++++++++++++---------
M
main.c
 | 
56
+++++++++++++++++++++++++++++++++++++++++++++++++++-----

2 files changed, 72 insertions(+), 14 deletions(-)
diff --git a/Makefile b/Makefile
@@ -1,13 +1,25 @@
-all:
-	gcc -g main.c exec.c disasm.c \
-	-Wall -Wextra -Wpedantic \
-	-Wconversion -Wsign-conversion \
-	-Wshadow -Wstrict-prototypes \
-	-Wmissing-prototypes -Wformat=2
+CC=gcc
+CPPFLAGS=
+CFLAGS= -g -Wall -Wextra -Wpedantic \
+      -Wconversion -Wsign-conversion \
+      -Wshadow -Wstrict-prototypes \
+      -Wmissing-prototypes -Wformat=2
+LFLAGS=
+
+ifeq ($(READLINE),1)
+	CPPFLAGS += -DHAVE_READLINE
+	LFLAGS += -lreadline
+endif
 
-test:
-	gcc -g rtests.c exec.c disasm.c \
-	-Wall -Wextra -Wpedantic \
+
+CFLAGS= -lreadline \
+	-g -Wall -Wextra -Wpedantic \
 	-Wconversion -Wsign-conversion \
 	-Wshadow -Wstrict-prototypes \
 	-Wmissing-prototypes -Wformat=2
+
+emu: exec.c exec.h disasm.c disasm.h trap.h mem.h main.c
+	$(CC) $(CPPFLAGS) $(CFLAGS) main.c exec.c disasm.c $(LFLAGS) -o $@
+
+test: exec.c exec.h disasm.c disasm.h trap.h mem.h rtests.c test.h
+	$(CC) $(CFLAGS) rtests.c exec.c disasm.c -o $@
diff --git a/main.c b/main.c
@@ -4,6 +4,11 @@
 #include <stdlib.h>
 #include <string.h>
 
+#ifdef HAVE_READLINE
+#include <readline/history.h>
+#include <readline/readline.h>
+#endif
+
 //#include "disasm.h"
 #include "exec.h"
 #include "mem.h"
@@ -17,7 +22,7 @@ typedef enum {
 static void
 load_program(uint8_t *mem)
 {
-	/* program */
+	/* PROGRAM */
 	uint32_t arr[] = {
 		0x10000593,	//li      a1,256
 		0xfff00513,	//li      a0,-1
@@ -38,6 +43,13 @@ load_program(uint8_t *mem)
 		0x0085a503,	//lw      a0,8(a1)
 		0x00000593,	//li      a1,0
 		0x00100073	//ebreak
+/*
+		0x20400093,     // addi x1,x0,0x204
+		0x12300113,     // addi x2,x0,0x123
+		0xfe20ae23,     // sw   x2,-4(x1) -> address 0x200
+		0xffc0a183,     // lw   x3,-4(x1)
+		0x00100073,     // ebreak
+*/
 	};
 
 	size_t len = sizeof(arr) / sizeof(arr[0]);
@@ -99,12 +111,27 @@ trap_handler(cpu_state_t *cpu)
 static emu_mode_t
 debugger(cpu_state_t *cpu, uint8_t *mem)
 {
+#ifdef HAVE_READLINE
+	char prompt[10];
+	snprintf(prompt, 10, "PC 0x%x>", cpu->pc);
+	char *line;
+	line = readline(prompt);
+	rl_bind_key('\t', rl_complete);
+
+	if (!line) {
+		free(line);
+		return MODE_STEP;
+	}
+	
+	add_history(line);
+#else
 	printf("PC 0x%x>", cpu->pc);
 	char line[256];
 	if (!fgets(line, sizeof(line), stdin)) {
 		fprintf(stderr, "Error reading"
 			"interactive input\n");
 	}
+#endif
 
 	if (strncmp(line, "s", 1) == 0 ||
 	    strncmp(line, "step", 4) == 0  ||
@@ -123,10 +150,23 @@ debugger(cpu_state_t *cpu, uint8_t *mem)
 		for (int i=0; i<32; i++) {
 			printf("x%d: 0x%x\n", i, cpu->x[i]);
 		}
-	} else if (strncmp(line, "m", 1) == 0 ||
-		   strncmp(line, "memory", 6) == 0) {
-		printf("Memory:\n");
-		for (uint32_t i=0; i<0x110; i+=4) {
+	} else if (strncmp(line, "x", 1) == 0) {
+		uint32_t from_addr = 0;
+		uint32_t count = 1;
+		sscanf(line, "x/%" SCNu32 " %" SCNx32, &count, &from_addr);
+
+		uint32_t xtarget = count*4 + from_addr;
+		/* TODO: probably some kind or helper or something */
+/*		if (xtarget+3 > MEMSIZE) {
+			printf("Out of bounds\n");
+#ifdef HAVE_READLINE
+			free(line);
+#endif
+			return MODE_RUN;
+		}
+*/
+		
+		for (uint32_t i=from_addr; i<xtarget; i+=4) {
 			if (cpu->pc == i) {
 				printf("-> ");
 			} else {
@@ -141,9 +181,15 @@ debugger(cpu_state_t *cpu, uint8_t *mem)
 		printf("Instruction poiter:\n");
 		printf("PC: %" PRIu32 "\n", cpu->pc);
 	} else if (strncmp(line, "e", 1) == 0) {
+#ifdef HAVE_READLINE
+		free(line);
+#endif
 		return MODE_RUN;
 	}
 
+#ifdef HAVE_READLINE
+	free(line);
+#endif
 	return MODE_STEP;
 }