commit - 14e785cef4f55c4cdaddd9bd6d98e4fa076d351f
commit + f0641b653b40f7b88979351e4bc56a32816ef84e
blob - dd689e20d4964ff3c5f13cea619551d57872c0e8
blob + c2068da3cd85736b579c59c2db99a0c031bf4e85
--- rvvm/rvhart.c
+++ rvvm/rvhart.c
@@ -66,7 +66,42 @@ rv_execute(struct rv_hart *h, struct rv_ram *m, struct
 	uint64_t 	next_pc = h->pc + RV_STEP_SIZE;
 
 	switch (i.opcode) {
-		// TODO: Implement execution logic.
+	case 0x13:
+		switch (i.funct3) {
+		case 0x0: // ADDI
+			h->rfile[i.rd] = h->rfile[i.rs1] + i.imm;
+			break;
+		case 0x4: // XORI
+			h->rfile[i.rd] = h-rfile[i.rs1] ^ i.imm;
+			break;
+		case 0x6: // ORI
+			h->rfile[i.rd] = h->rfile[i.rs1] | i.imm;
+			break;
+		case 0x7: // ANDI
+			h->rfile[i.rd] = h->rfile[i.rs1] & i.imm;
+			break;
+		default:
+			err(1, "rv_execute(): unknown funct3 %x for OP-IMM", i.funct3);
+		}
+		break;
+	case 0x33:
+		switch (i.funct3) {
+		case 0x0:
+			if (i.funct7 == 0x20)
+				h->rfile[i.rd] = h->rfile[i.rs1] - h->rfile[i.rs2];
+			else
+				h->rfile[i.rd] = h->rfile[i.rs1] + h->rfile[i.rs2];
+			break;
+		case 0x7:
+			h->rfile[i.rd] = h->rfile[i.rs1] & h->rfile[i.rs2];
+			break;
+		default:
+			err(1, "rv_execute(): unknown funct3 %x for OP", i.funct3);
+		}
+		break;
+	case 0x37: // LUI
+		h->rfile[i.rd] = i.imm;
+		break;
 	default:
 		err(1, "rv_execute(): unknown opcode %x", i.opcode);
 	}
@@ -82,5 +117,5 @@ rv_step(struct rv_hart *h, struct rv_ram *m) {
 	
 	word	= (uint32_t)rv_ram_read(m, h->pc);
 	i 	= rv_decode(word);
-	rv_execute(h, i);
+	rv_execute(h, m, i);
 }
blob - 224142c566e514d83c4b78b582b8dd318f01ad59
blob + 26ebe47523c7b52e09d66de178471ee5652bbfbb
--- rvvm/rvram.c
+++ rvvm/rvram.c
@@ -3,3 +3,10 @@
 #include <string.h>
 
 #include "rvram.h"
+
+uint64_t
+rv_ram_read(struct rv_ram *m, uint64_t addr)
+{
+	uint64_t offset = addr - m->base_addr;
+	return (uint64_t)(*(uint32_t *)&m->data[offset]);
+}
blob - 9d787bc887285367dc41570fc57e4ba1825021aa
blob + a049c1b3924f3e2d4c44bb988b84751fce8789bb
--- rvvm/rvram.h
+++ rvvm/rvram.h
@@ -4,6 +4,8 @@
 #include <stdint.h>
 
 struct rv_ram {
-	// ...
+	uint8_t		*data;
+	uint64_t	base_addr;
+	size_t		size;
 };
 #endif