diff --git a/include/mos6502.h b/include/mos6502.h
index ea7c73f..062a3f1 100644
--- a/include/mos6502.h
+++ b/include/mos6502.h
@@ -172,7 +172,6 @@ extern vm_8bit mos6502_pop_stack(mos6502 *);
 extern void mos6502_execute(mos6502 *);
 extern void mos6502_free(mos6502 *);
 extern void mos6502_last_executed(mos6502 *, vm_8bit *, vm_8bit *, vm_16bit *);
-extern void mos6502_modify_status(mos6502 *, vm_8bit, int, int);
 extern void mos6502_push_stack(mos6502 *, vm_8bit);
 extern void mos6502_set(mos6502 *, size_t, vm_8bit);
 extern void mos6502_set16(mos6502 *, size_t, vm_16bit);
diff --git a/src/mos6502.c b/src/mos6502.c
index 2d95fac..cc785e9 100644
--- a/src/mos6502.c
+++ b/src/mos6502.c
@@ -237,58 +237,6 @@ mos6502_set_status(mos6502 *cpu, vm_8bit status)
     cpu->P = status;
 }
 
-/*
- * In contrast, the modify_status function will conditionally set the
- * contents of certain bits, based upon the value of the operand. Those
- * bits are the negative, overflow, carry, and zero flags.
- */
-void
-mos6502_modify_status(mos6502 *cpu, vm_8bit status, int orig, int result)
-{
-    int bit7o, bit7r;
-
-    if (status & MOS_NEGATIVE) {
-        cpu->P &= ~MOS_NEGATIVE;
-        if (result & 0x80) {
-            cpu->P |= MOS_NEGATIVE;
-        }
-    }
-
-    if (status & MOS_OVERFLOW) {
-        cpu->P &= ~MOS_OVERFLOW;
-
-        bit7o = orig & 0x80;
-        bit7r = result & 0x80;
-
-        // If the result of the operation is such that the sign bit,
-        // that is to say bit 7, changes, then we have overflowed. E.g.:
-        // 90 + 40 = 130, but that's actually -124 in two's complement.
-        // So if you are paying attention to the sign, you have
-        // overflowed from a positive into a negative result.
-        if (bit7o ^ bit7r) {
-            cpu->P |= MOS_OVERFLOW;
-        }
-    }
-
-    if (status & MOS_CARRY) {
-        cpu->P &= ~MOS_CARRY;
-
-        // The result of the operation requires 9 bits to hold, but we
-        // can only hold 8 bits; rather than lose that bit's value, it
-        // is held in the carry bit of the P register.
-        if (result > 0xFF) {
-            cpu->P |= MOS_CARRY;
-        }
-    }
-
-    if (status & MOS_ZERO) {
-        cpu->P &= ~MOS_ZERO;
-        if ((result & 0xff) == 0) {
-            cpu->P |= MOS_ZERO;
-        }
-    }
-}
-
 /*
  * Return the instruction that is mapped to a given opcode.
  */
diff --git a/tests/mos6502.c b/tests/mos6502.c
index 060eafb..85e4a6e 100644
--- a/tests/mos6502.c
+++ b/tests/mos6502.c
@@ -37,24 +37,19 @@ Test(mos6502, pop_stack)
 
 Test(mos6502, modify_status)
 {
-    mos6502_modify_status(cpu, MOS_NEGATIVE, 130, 130);
+    MOS_CHECK_N(130);
     cr_assert_eq(cpu->P & MOS_NEGATIVE, MOS_NEGATIVE);
-    mos6502_modify_status(cpu, MOS_NEGATIVE, 123, 123);
+    MOS_CHECK_N(123);
     cr_assert_neq(cpu->P & MOS_NEGATIVE, MOS_NEGATIVE);
 
-    mos6502_modify_status(cpu, MOS_OVERFLOW, 123, 133);
+    MOS_CHECK_V(123, 133);
     cr_assert_eq(cpu->P & MOS_OVERFLOW, MOS_OVERFLOW);
-    mos6502_modify_status(cpu, MOS_OVERFLOW, 44, 44);
+    MOS_CHECK_V(44, 44);
     cr_assert_neq(cpu->P & MOS_OVERFLOW, MOS_OVERFLOW);
 
-    mos6502_modify_status(cpu, MOS_CARRY, 230, 260);
-    cr_assert_eq(cpu->P & MOS_CARRY, MOS_CARRY);
-    mos6502_modify_status(cpu, MOS_CARRY, 30, 190);
-    cr_assert_neq(cpu->P & MOS_CARRY, MOS_CARRY);
-
-    mos6502_modify_status(cpu, MOS_ZERO, 0, 0);
+    MOS_CHECK_Z(0);
     cr_assert_eq(cpu->P & MOS_ZERO, MOS_ZERO);
-    mos6502_modify_status(cpu, MOS_ZERO, 1, 1);
+    MOS_CHECK_Z(1);
     cr_assert_neq(cpu->P & MOS_ZERO, MOS_ZERO);
 }