diff --git a/disasm/src/generated.rs b/disasm/src/generated.rs
index 395afa6..4006744 100644
--- a/disasm/src/generated.rs
+++ b/disasm/src/generated.rs
@@ -5708,17 +5708,6 @@ impl Ins {
                         ins: self,
                     };
                 }
-                if (((((self.code >> 11u8) & 0x3ff) & 0b11111_00000u32) >> 5u32)
-                    | ((((self.code >> 11u8) & 0x3ff) & 0b00000_11111u32) << 5u32))
-                    as u32
-                    == 571
-                {
-                    return SimplifiedIns {
-                        mnemonic: "mftdu",
-                        args: vec![Argument::GPR(GPR(((self.code >> 21u8) & 0x1f) as _))],
-                        ins: self,
-                    };
-                }
             }
             Opcode::Mtspr => {
                 if (((((self.code >> 11u8) & 0x3ff) & 0b11111_00000u32) >> 5u32)
@@ -5776,17 +5765,6 @@ impl Ins {
                         ins: self,
                     };
                 }
-                if (((((self.code >> 11u8) & 0x3ff) & 0b11111_00000u32) >> 5u32)
-                    | ((((self.code >> 11u8) & 0x3ff) & 0b00000_11111u32) << 5u32))
-                    as u32
-                    == 571
-                {
-                    return SimplifiedIns {
-                        mnemonic: "mttdu",
-                        args: vec![Argument::GPR(GPR(((self.code >> 21u8) & 0x1f) as _))],
-                        ins: self,
-                    };
-                }
             }
             Opcode::Or => {
                 if ((self.code >> 21u8) & 0x1f) == ((self.code >> 11u8) & 0x1f) {
diff --git a/isa.yaml b/isa.yaml
index c70de96..00a459c 100644
--- a/isa.yaml
+++ b/isa.yaml
@@ -2103,10 +2103,6 @@ mnemonics:
     opcode: mtspr
     args: [ rS ]
     condition: spr == 397
-  - name: mttdu
-    opcode: mtspr
-    args: [ rS ]
-    condition: spr == 571
 
   # Move from special-purpose register
   - name: mfxer
@@ -2129,10 +2125,6 @@ mnemonics:
     opcode: mfspr
     args: [ rD ]
     condition: spr == 397
-  - name: mftdu
-    opcode: mfspr
-    args: [ rD ]
-    condition: spr == 571
 
   # Branch Conditional
   # bc branch always