diff --git a/build.sh b/build.sh
index 9a99dad..890df72 100755
--- a/build.sh
+++ b/build.sh
@@ -1,15 +1,15 @@
 #!/bin/bash
 
-WARNINGS="-Wall -Wextra -Wpedantic -Wno-unused-variable -Wno-gnu-binary-literal"
+COMMON="-g -Wall -Wextra -Wpedantic -Wno-unused-variable -Wno-gnu-binary-literal"
 
 echo "building mos6502..."
-cc $WARNINGS -std=c99 -o mos6502 mos6502.c
+cc $COMMON -std=c99 -o mos6502 mos6502.c
 
 if command -v pkg-config >/dev/null; then
     RAYLIB_FLAGS=$(pkg-config --cflags --libs raylib 2>/dev/null)
     if [ $? -eq 0 ]; then
         echo "building chip8..."
-        cc $WARNINGS -std=c99 -o chip8 chip8.c $RAYLIB_FLAGS
+        cc $COMMON -std=c99 -o chip8 chip8.c $RAYLIB_FLAGS
     else
         echo "raylib not found - skipping chip8..."
     fi
@@ -17,7 +17,7 @@ if command -v pkg-config >/dev/null; then
     LIBELF_FLAGS=$(pkg-config --cflags --libs libelf 2>/dev/null)
     if [ $? -eq 0 ]; then
         echo "building riscv64..."
-        cc $WARNINGS -std=gnu11 -o riscv64 riscv64.c $LIBELF_FLAGS
+        cc $COMMON -std=gnu11 -o riscv64 riscv64.c $LIBELF_FLAGS
     else
         echo "libelf not found - skipping riscv64..."
     fi
diff --git a/riscv64.c b/riscv64.c
index 47dc8e7..27acbaf 100644
--- a/riscv64.c
+++ b/riscv64.c
@@ -63,6 +63,7 @@ static const char *const REGS[32] = {
 typedef struct {
   size_t offset;
   size_t size;
+  size_t entrypoint;
 } Section;
 
 typedef struct {
@@ -85,6 +86,12 @@ Section riscv64_get_code_section(uint8_t *exe_bytes, size_t exe_size) {
     exit(1);
   }
 
+  GElf_Ehdr ehdr;
+  if (gelf_getehdr(elf, &ehdr) == 0) {
+    fprintf(stderr, "gelf_getehdr failed: %s\n", elf_errmsg(-1));
+    exit(1);
+  }
+
   Elf_Scn *section = NULL;
   while ((section = elf_nextscn(elf, section)) != NULL) {
     GElf_Shdr header;
@@ -94,7 +101,10 @@ Section riscv64_get_code_section(uint8_t *exe_bytes, size_t exe_size) {
     const char *name = elf_strptr(elf, str_table_index, header.sh_name);
     if (name && strcmp(name, ".text") == 0) {
       elf_end(elf);
-      return (Section){.offset = header.sh_offset, .size = header.sh_size};
+      return (Section){.offset = header.sh_offset,
+                       .size = header.sh_size,
+                       .entrypoint =
+                           ehdr.e_entry - header.sh_addr + header.sh_offset};
     }
   }
 
@@ -140,7 +150,8 @@ void riscv64_disassemble_one(const RISCV64 *r) {
       printf("blt %s, %s, %d\n", REGS[rs1], REGS[rs2], imm);
     } else if (funct3 == 0b101) {
       printf("bge %s, %s, %d\n", REGS[rs1], REGS[rs2], imm);
-      break;
+    } else if (funct3 == 0b110) {
+      printf("bltu %s, %s, %d\n", REGS[rs1], REGS[rs2], imm);
     } else {
       fprintf(stderr, "B-type: unrecognized funct3: %03b\n", funct3);
       exit(1);
@@ -152,7 +163,36 @@ void riscv64_disassemble_one(const RISCV64 *r) {
     if (funct3 == 0b000) {
       printf("addi %s, %s, %d\n", REGS[rd], REGS[rs1], imm);
     } else if (funct3 == 0b001) {
-      printf("slli %s, %s, %d\n", REGS[rd], REGS[rs1], imm);
+      uint32_t shamt = (ins >> 20) & 0b111111;
+      uint32_t funct6 = (ins >> 26) & 0b111111;
+
+      if (funct6 == 0b000000) {
+        printf("slli %s, %s, %d\n", REGS[rd], REGS[rs1], shamt);
+      } else {
+        fprintf(stderr, "I-type 1: funct3=001: unrecognized funct6: %b\n",
+                funct6);
+        exit(1);
+      }
+    } else if (funct3 == 0b011) {
+      printf("sltiu %s, %s, %d\n", REGS[rd], REGS[rs1], imm);
+    } else if (funct3 == 0b100) {
+      printf("xori %s, %s, %d\n", REGS[rd], REGS[rs1], imm);
+    } else if (funct3 == 0b101) {
+      // of course this one just has to be different
+      uint32_t shamt = (ins >> 20) & 0b111111;
+      uint32_t funct6 = (ins >> 26) & 0b111111;
+
+      if (funct6 == 0b000000) {
+        printf("srli %s, %s, %d\n", REGS[rd], REGS[rs1], shamt);
+      } else if (funct6 == 0b010000) {
+        printf("srai %s, %s, %d\n", REGS[rd], REGS[rs1], shamt);
+      } else {
+        fprintf(stderr, "I-type 1: funct3=101: unrecognized funct6: %b\n",
+                funct6);
+        exit(1);
+      }
+    } else if (funct3 == 0b111) {
+      printf("andi %s, %s, %d\n", REGS[rd], REGS[rs1], imm);
     } else {
       fprintf(stderr, "I-type 1: unrecognized funct3: %03b\n", funct3);
       exit(1);
@@ -163,8 +203,14 @@ void riscv64_disassemble_one(const RISCV64 *r) {
 
     if (funct3 == 0b000) {
       printf("lb %s, %d(%s)\n", REGS[rd], imm, REGS[rs1]);
+    } else if (funct3 == 0b001) {
+      printf("lh %s, %d(%s)\n", REGS[rd], imm, REGS[rs1]);
+    } else if (funct3 == 0b010) {
+      printf("lw %s, %d(%s)\n", REGS[rd], imm, REGS[rs1]);
     } else if (funct3 == 0b011) {
       printf("ld %s, %d(%s)\n", REGS[rd], imm, REGS[rs1]);
+    } else if (funct3 == 0b100) {
+      printf("lbu %s, %d(%s)\n", REGS[rd], imm, REGS[rs1]);
     } else {
       fprintf(stderr, "I-type 2: unrecognized funct3: %03b\n", funct3);
       exit(1);
@@ -184,7 +230,6 @@ void riscv64_disassemble_one(const RISCV64 *r) {
         fprintf(stderr, "I-type 4: funct3=000 unrecognized imm: %b\n", imm);
         exit(1);
       }
-      break;
     } else {
       fprintf(stderr, "I-type 4: unrecognized funct3: %03b\n", funct3);
       exit(1);
@@ -208,6 +253,60 @@ void riscv64_disassemble_one(const RISCV64 *r) {
                 funct7);
         exit(1);
       }
+    } else if (funct3 == 0b001) {
+      if (funct7 == 0b0000001) {
+        printf("mulh %s, %s, %s\n", REGS[rd], REGS[rs1], REGS[rs2]);
+      } else {
+        fprintf(stderr, "R-type 1: funct3=0b001: unrecognized funct7: %b\n",
+                funct7);
+        exit(1);
+      }
+    } else if (funct3 == 0b010) {
+      if (funct7 == 0b0000000) {
+        printf("slt %s, %s, %s\n", REGS[rd], REGS[rs1], REGS[rs2]);
+      } else {
+        fprintf(stderr, "R-type 1: funct3=0b010: unrecognized funct7: %b\n",
+                funct7);
+        exit(1);
+      }
+    } else if (funct3 == 0b011) {
+      if (funct7 == 0b0000000) {
+        printf("sltu %s, %s, %s\n", REGS[rd], REGS[rs1], REGS[rs2]);
+      } else if (funct7 == 0b0000001) {
+        printf("mulhu %s, %s, %s\n", REGS[rd], REGS[rs1], REGS[rs2]);
+      } else {
+        fprintf(stderr, "R-type 1: funct3=0b011: unrecognized funct7: %b\n",
+                funct7);
+        exit(1);
+      }
+    } else if (funct3 == 0b100) {
+      if (funct7 == 0b0000000) {
+        printf("xor %s, %s, %s\n", REGS[rd], REGS[rs1], REGS[rs2]);
+      } else if (funct7 == 0b0000001) {
+        printf("div %s, %s, %s\n", REGS[rd], REGS[rs1], REGS[rs2]);
+      } else {
+        fprintf(stderr, "R-type 1: funct3=0b100: unrecognized funct7: %b\n",
+                funct7);
+        exit(1);
+      }
+    } else if (funct3 == 0b110) {
+      if (funct7 == 0b0000001) {
+        printf("rem %s, %s, %s\n", REGS[rd], REGS[rs1], REGS[rs2]);
+      } else if (funct7 == 0b0000000) {
+        printf("or %s, %s, %s\n", REGS[rd], REGS[rs1], REGS[rs2]);
+      } else {
+        fprintf(stderr, "R-type 1: funct3=0b110: unrecognized funct7: %b\n",
+                funct7);
+        exit(1);
+      }
+    } else if (funct3 == 0b111) {
+      if (funct7 == 0b000) {
+        printf("and %s, %s, %s\n", REGS[rd], REGS[rs1], REGS[rs2]);
+      } else {
+        fprintf(stderr, "R-type 1: funct3=0b111: unrecognized funct7: %b\n",
+                funct7);
+        exit(1);
+      }
     } else {
       fprintf(stderr, "R-type 1: unrecognized funct3: %03b\n", funct3);
       exit(1);
@@ -218,7 +317,19 @@ void riscv64_disassemble_one(const RISCV64 *r) {
     exit(1);
   case 0b0111011: {
     PARSE_R_INS(ins);
-    if (funct3 == 0b101) {
+    if (funct3 == 0b000) {
+      if (funct7 == 0b0000000) {
+        printf("addw %s, %s, %s\n", REGS[rd], REGS[rs1], REGS[rs2]);
+      } else if (funct7 == 0b0100000) {
+        printf("subw %s, %s, %s\n", REGS[rd], REGS[rs1], REGS[rs2]);
+      } else if (funct7 == 0b0000001) {
+        printf("mulw %s, %s, %s\n", REGS[rd], REGS[rs1], REGS[rs2]);
+      } else {
+        fprintf(stderr, "R-type 3: funct3=000: unrecognized funct7: %b\n",
+                funct7);
+        exit(1);
+      }
+    } else if (funct3 == 0b101) {
       if (funct7 == 0b0000001) {
         printf("divuw %s, %s, %s\n", REGS[rd], REGS[rs1], REGS[rs2]);
       } else {
@@ -238,6 +349,9 @@ void riscv64_disassemble_one(const RISCV64 *r) {
     if (funct3 == 0b000) {
       PARSE_I_INS(ins);
       printf("addiw %s, %s, %d\n", REGS[rd], REGS[rs1], imm);
+    } else if (funct3 == 0b001) {
+      PARSE_I_INS(ins);
+      printf("slliw %s, %s, %d\n", REGS[rd], REGS[rs1], imm);
     } else {
       fprintf(stderr, "R-type 4: unrecognized funct3: %03b\n", funct3);
       exit(1);
@@ -248,6 +362,10 @@ void riscv64_disassemble_one(const RISCV64 *r) {
 
     if (funct3 == 0b000) {
       printf("sb %s, %d(%s)\n", REGS[rs2], imm, REGS[rs1]);
+    } else if (funct3 == 0b001) {
+      printf("sh %s, %d(%s)\n", REGS[rs2], imm, REGS[rs1]);
+    } else if (funct3 == 0b010) {
+      printf("sw %s, %d(%s)\n", REGS[rs2], imm, REGS[rs1]);
     } else if (funct3 == 0b011) {
       printf("sd %s, %d(%s)\n", REGS[rs2], imm, REGS[rs1]);
     } else {
@@ -270,7 +388,7 @@ void riscv64_disassemble_one(const RISCV64 *r) {
 }
 
 void riscv64_execute(RISCV64 *r) {
-  r->pc = r->code_section.offset;
+  r->pc = r->code_section.entrypoint;
 
   r->regs[2] = (20 * 1024 * 1024) - 1; // set the stack pointer
 
@@ -307,6 +425,11 @@ void riscv64_execute(RISCV64 *r) {
           r->pc += imm;
           continue;
         }
+      } else if (funct3 == 0b110) { // bltu
+        if ((uint64_t)r->regs[rs1] < (uint64_t)r->regs[rs2]) {
+          r->pc += imm;
+          continue;
+        }
       } else {
         fprintf(stderr, "B-type: unrecognized funct3: %03b\n", funct3);
         exit(1);
@@ -318,7 +441,36 @@ void riscv64_execute(RISCV64 *r) {
       if (funct3 == 0b000) { // addi
         r->regs[rd] = r->regs[rs1] + imm;
       } else if (funct3 == 0b001) { // slli
-        r->regs[rd] = r->regs[rs1] << (imm & 0b111111);
+        uint32_t shamt = (ins >> 20) & 0b111111;
+        uint32_t funct6 = (ins >> 26) & 0b111111;
+
+        if (funct6 == 0b000000) {
+          r->regs[rd] = r->regs[rs1] << shamt;
+        } else {
+          fprintf(stderr, "I-type 1: funct3=001: unrecognized funct6: %b\n",
+                  funct6);
+          exit(1);
+        }
+      } else if (funct3 == 0b011) { // sltiu
+        r->regs[rd] = (r->regs[rs1] < (uint64_t)(int64_t)imm) ? 1 : 0;
+      } else if (funct3 == 0b100) { // xori
+        r->regs[rd] = r->regs[rs1] ^ imm;
+      } else if (funct3 == 0b101) {
+        // of course this one just has to be different
+        uint32_t shamt = (ins >> 20) & 0b111111;
+        uint32_t funct6 = (ins >> 26) & 0b111111;
+
+        if (funct6 == 0b000000) { // srli
+          r->regs[rd] = r->regs[rs1] >> shamt;
+        } else if (funct6 == 0b010000) { // srai
+          r->regs[rd] = (int32_t)r->regs[rs1] >> shamt;
+        } else {
+          fprintf(stderr, "I-type 1: funct3=101: unrecognized funct6: %b\n",
+                  funct6);
+          exit(1);
+        }
+      } else if (funct3 == 0b111) {
+        r->regs[rd] = r->regs[rs1] & imm;
       } else {
         fprintf(stderr, "I-type 1: unrecognized funct3: %03b\n", funct3);
         exit(1);
@@ -328,9 +480,15 @@ void riscv64_execute(RISCV64 *r) {
       PARSE_I_INS(ins);
 
       if (funct3 == 0b000) { // lb
-        r->regs[rd] = r->memory[r->regs[rs1] + imm];
+        r->regs[rd] = (int8_t)r->memory[r->regs[rs1] + imm];
+      } else if (funct3 == 0b001) { // lh
+        r->regs[rd] = *(int16_t *)&r->memory[r->regs[rs1] + imm];
+      } else if (funct3 == 0b010) { // lw
+        r->regs[rd] = *(int32_t *)&r->memory[r->regs[rs1] + imm];
       } else if (funct3 == 0b011) { // ld
         r->regs[rd] = *(uint64_t *)&r->memory[r->regs[rs1] + imm];
+      } else if (funct3 == 0b100) { // lbu
+        r->regs[rd] = r->memory[r->regs[rs1] + imm];
       } else {
         fprintf(stderr, "I-type 2: unrecognized funct3: %03b\n", funct3);
         exit(1);
@@ -338,7 +496,7 @@ void riscv64_execute(RISCV64 *r) {
     }; break;
     case 0b1100111: { // jalr
       PARSE_I_INS(ins);
-      uint32_t target = (r->regs[rs1] + imm) & ~1;
+      size_t target = (r->regs[rs1] + imm) & ~(size_t)1;
       r->regs[rd] = r->pc + 4;
       r->pc = target;
       continue;
@@ -432,18 +590,86 @@ void riscv64_execute(RISCV64 *r) {
       if (funct3 == 0b000) {
         if (funct7 == 0b0000000) { // add
           r->regs[rd] = r->regs[rs1] + r->regs[rs2];
-          break;
         } else if (funct7 == 0b0100000) { // sub
           r->regs[rd] = r->regs[rs1] - r->regs[rs2];
-          break;
         } else if (funct7 == 0b0000001) { // mul
           r->regs[rd] = r->regs[rs1] * r->regs[rs2];
-          break;
         } else {
           fprintf(stderr, "R-type 1: funct3=0b000: unrecognized funct7: %b\n",
                   funct7);
           exit(1);
         }
+      } else if (funct3 == 0b001) {
+        if (funct7 == 0b0000001) { // mulh
+          int64_t a_hi = r->regs[rs1] >> 32;
+          int64_t b_hi = r->regs[rs2] >> 32;
+          uint64_t a_lo = (uint32_t)r->regs[rs1];
+          uint64_t b_lo = (uint32_t)r->regs[rs2];
+          uint64_t p0 = a_lo * b_lo;
+          int64_t p1 = a_hi * b_lo;
+          int64_t p2 = b_hi * a_lo;
+          int64_t p3 = a_hi * b_hi;
+          int64_t carry = (p0 >> 32);
+          int64_t mid = p1 + p2 + carry;
+          r->regs[rd] = p3 + (mid >> 32);
+        } else {
+          fprintf(stderr, "R-type 1: funct3=0b001: unrecognized funct7: %b\n",
+                  funct7);
+          exit(1);
+        }
+      } else if (funct3 == 0b010) {
+        if (funct7 == 0b0000000) { // slt
+          r->regs[rd] = ((int64_t)r->regs[rs1] < (int64_t)r->regs[rs2]) ? 1 : 0;
+        } else {
+          fprintf(stderr, "R-type 1: funct3=0b010: unrecognized funct7: %b\n",
+                  funct7);
+          exit(1);
+        }
+      } else if (funct3 == 0b011) {
+        if (funct7 == 0b0000000) { // sltu
+          r->regs[rd] =
+              ((uint64_t)r->regs[rs1] < (uint64_t)r->regs[rs2]) ? 1 : 0;
+        } else {
+          fprintf(stderr, "R-type 1: funct3=0b011: unrecognized funct7: %b\n",
+                  funct7);
+          exit(1);
+        }
+      } else if (funct3 == 0b100) {
+        if (funct7 == 0b0000000) { // xor
+          r->regs[rd] = r->regs[rs1] ^ r->regs[rs2];
+        } else if (funct7 == 0b0000001) { // div
+          if (r->regs[rs2] == 0) {
+            r->regs[rd] = -1;
+          } else {
+            r->regs[rd] = (int64_t)r->regs[rs1] / (int64_t)r->regs[rs2];
+          }
+        } else {
+          fprintf(stderr, "R-type 1: funct3=0b100: unrecognized funct7: %b\n",
+                  funct7);
+          exit(1);
+        }
+      } else if (funct3 == 0b110) {
+        if (funct7 == 0b0000001) { // rem
+          if (r->regs[rs2] == 0) {
+            r->regs[rd] = r->regs[rs1];
+          } else {
+            r->regs[rd] = (int64_t)r->regs[rs1] % (int64_t)r->regs[rs2];
+          }
+        } else if (funct7 == 0b0000000) { // or
+          r->regs[rd] = r->regs[rs1] | r->regs[rs2];
+        } else {
+          fprintf(stderr, "R-type 1: funct3=0b110: unrecognized funct7: %b\n",
+                  funct7);
+          exit(1);
+        }
+      } else if (funct3 == 0b111) {
+        if (funct7 == 0b000) { // and
+          r->regs[rd] = r->regs[rs1] & r->regs[rs2];
+        } else {
+          fprintf(stderr, "R-type 1: funct3=0b111: unrecognized funct7: %b\n",
+                  funct7);
+          exit(1);
+        }
       } else {
         fprintf(stderr, "R-type 1: unrecognized funct3: %03b\n", funct3);
         exit(1);
@@ -451,23 +677,37 @@ void riscv64_execute(RISCV64 *r) {
     }; break;
     case 0b0111011: {
       PARSE_R_INS(ins);
-      if (funct3 == 0b101) {
-        if (funct7 == 0b0000001) {
+      if (funct3 == 0b000) {
+        if (funct7 == 0b0000000) { // addw
+          r->regs[rd] = (int32_t)(r->regs[rs1] + r->regs[rs2]);
+        } else if (funct7 == 0b0100000) { // subw
+          r->regs[rd] = (int32_t)(r->regs[rs1] - r->regs[rs2]);
+        } else if (funct7 == 0b0000001) { // mulw
+          r->regs[rd] = (int32_t)(r->regs[rs1] * r->regs[rs2]);
+        } else {
+          fprintf(stderr, "R-type 3: funct3=000: unrecognized funct7: %b\n",
+                  funct7);
+          exit(1);
+        }
+      } else if (funct3 == 0b101) {
+        if (funct7 == 0b0000001) { // divuw
           if (r->regs[rs2] == 0) {
             r->regs[rd] = -1LL;
           } else {
-            r->regs[rd] = (int32_t)(r->regs[rs1] / r->regs[rs2]);
+            r->regs[rd] =
+                (int32_t)((uint32_t)r->regs[rs1] / (uint32_t)r->regs[rs2]);
           }
         } else {
           fprintf(stderr, "R-type 3: funct3=101: unrecognized funct7: %b\n",
                   funct7);
           exit(1);
         }
-      } else if (funct3 == 0b111) {
+      } else if (funct3 == 0b111) { // remuw
         if (r->regs[rs2] == 0) {
           r->regs[rd] = (int32_t)r->regs[rs1];
         } else {
-          r->regs[rd] = (int32_t)(r->regs[rs1] % r->regs[rs2]);
+          r->regs[rd] =
+              (int32_t)((uint32_t)r->regs[rs1] % (uint32_t)r->regs[rs2]);
         }
       } else {
         fprintf(stderr, "R-type 3: unrecognized funct3: %03b\n", funct3);
@@ -475,11 +715,12 @@ void riscv64_execute(RISCV64 *r) {
       }
     }; break;
     case 0b0011011: {
-      uint8_t funct3 = (ins >> 12) & 0b111;
-      if (funct3 == 0b000) {
-        PARSE_I_INS(ins);
-        int32_t result = r->regs[rs1] + imm;
-        r->regs[rd] = result;
+      PARSE_I_INS(ins);
+      if (funct3 == 0b000) { // addiw
+        r->regs[rd] = (int32_t)r->regs[rs1] + (int32_t)imm;
+      } else if (funct3 == 0b001) {
+        uint32_t shamt = (ins >> 20) & 0b11111;
+        r->regs[rd] = (int32_t)r->regs[rs1] << shamt;
       } else {
         fprintf(stderr, "R-type 4: unrecognized funct3: %03b\n", funct3);
         exit(1);
@@ -491,6 +732,12 @@ void riscv64_execute(RISCV64 *r) {
       if (funct3 == 0b000) { // sb
         size_t addr = r->regs[rs1] + imm;
         r->memory[addr] = r->regs[rs2];
+      } else if (funct3 == 0b001) { // sh
+        size_t addr = r->regs[rs1] + imm;
+        *(uint16_t *)(&r->memory[addr]) = r->regs[rs2];
+      } else if (funct3 == 0b010) { // sw
+        size_t addr = r->regs[rs1] + imm;
+        *(uint32_t *)(&r->memory[addr]) = r->regs[rs2];
       } else if (funct3 == 0b011) { // sd
         size_t addr = r->regs[rs1] + imm;
         // take this rust
@@ -502,11 +749,11 @@ void riscv64_execute(RISCV64 *r) {
     }; break;
     case 0b0110111: { // lui
       PARSE_U_INS(ins);
-      r->regs[rd] = imm << 12;
+      r->regs[rd] = (int64_t)imm << 12;
     }; break;
     case 0b0010111: { // auipc
       PARSE_U_INS(ins);
-      r->regs[rd] = r->pc + (imm << 12);
+      r->regs[rd] = r->pc + ((int64_t)imm << 12);
     }; break;
     default:
       fprintf(stderr, "Unrecognized opcode: %07b\n", opcode);