diff --git a/cranelift/fuzzgen/src/function_generator.rs b/cranelift/fuzzgen/src/function_generator.rs
index 5e8fcefc2a..88e0f62efc 100644
--- a/cranelift/fuzzgen/src/function_generator.rs
+++ b/cranelift/fuzzgen/src/function_generator.rs
@@ -277,6 +277,72 @@ const OPCODE_SIGNATURES: &'static [(
     //   aarch64: https://github.com/bytecodealliance/wasmtime/issues/4864
     #[cfg(not(any(target_arch = "x86_64", target_arch = "aarch64")))]
     (Opcode::Sdiv, &[I128, I128], &[I128], insert_opcode),
+    // Ineg
+    (Opcode::Ineg, &[I8, I8], &[I8], insert_opcode),
+    (Opcode::Ineg, &[I16, I16], &[I16], insert_opcode),
+    (Opcode::Ineg, &[I32, I32], &[I32], insert_opcode),
+    (Opcode::Ineg, &[I64, I64], &[I64], insert_opcode),
+    // ineg.i128 not implemented in some backends:
+    //   x64: https://github.com/bytecodealliance/wasmtime/issues/5105
+    //   aarch64: https://github.com/bytecodealliance/wasmtime/issues/5108
+    #[cfg(not(any(target_arch = "x86_64", target_arch = "aarch64")))]
+    (Opcode::Ineg, &[I128, I128], &[I128], insert_opcode),
+    // Imin
+    // imin not implemented in some backends:
+    //   x64: https://github.com/bytecodealliance/wasmtime/issues/3370
+    //   aarch64: https://github.com/bytecodealliance/wasmtime/issues/4313
+    #[cfg(not(target_arch = "aarch64"))]
+    (Opcode::Imin, &[I8, I8], &[I8], insert_opcode),
+    #[cfg(not(target_arch = "aarch64"))]
+    (Opcode::Imin, &[I16, I16], &[I16], insert_opcode),
+    #[cfg(not(target_arch = "aarch64"))]
+    (Opcode::Imin, &[I32, I32], &[I32], insert_opcode),
+    #[cfg(not(target_arch = "aarch64"))]
+    (Opcode::Imin, &[I64, I64], &[I64], insert_opcode),
+    #[cfg(not(any(target_arch = "x86_64", target_arch = "aarch64")))]
+    (Opcode::Imin, &[I128, I128], &[I128], insert_opcode),
+    // Umin
+    // umin not implemented in some backends:
+    //   x64: https://github.com/bytecodealliance/wasmtime/issues/3370
+    //   aarch64: https://github.com/bytecodealliance/wasmtime/issues/4313
+    #[cfg(not(target_arch = "aarch64"))]
+    (Opcode::Umin, &[I8, I8], &[I8], insert_opcode),
+    #[cfg(not(target_arch = "aarch64"))]
+    (Opcode::Umin, &[I16, I16], &[I16], insert_opcode),
+    #[cfg(not(target_arch = "aarch64"))]
+    (Opcode::Umin, &[I32, I32], &[I32], insert_opcode),
+    #[cfg(not(target_arch = "aarch64"))]
+    (Opcode::Umin, &[I64, I64], &[I64], insert_opcode),
+    #[cfg(not(any(target_arch = "x86_64", target_arch = "aarch64")))]
+    (Opcode::Umin, &[I128, I128], &[I128], insert_opcode),
+    // Imax
+    // imax not implemented in some backends:
+    //   x64: https://github.com/bytecodealliance/wasmtime/issues/3370
+    //   aarch64: https://github.com/bytecodealliance/wasmtime/issues/4313
+    #[cfg(not(target_arch = "aarch64"))]
+    (Opcode::Imax, &[I8, I8], &[I8], insert_opcode),
+    #[cfg(not(target_arch = "aarch64"))]
+    (Opcode::Imax, &[I16, I16], &[I16], insert_opcode),
+    #[cfg(not(target_arch = "aarch64"))]
+    (Opcode::Imax, &[I32, I32], &[I32], insert_opcode),
+    #[cfg(not(target_arch = "aarch64"))]
+    (Opcode::Imax, &[I64, I64], &[I64], insert_opcode),
+    #[cfg(not(any(target_arch = "x86_64", target_arch = "aarch64")))]
+    (Opcode::Imax, &[I128, I128], &[I128], insert_opcode),
+    // Umax
+    // umax not implemented in some backends:
+    //   x64: https://github.com/bytecodealliance/wasmtime/issues/3370
+    //   aarch64: https://github.com/bytecodealliance/wasmtime/issues/4313
+    #[cfg(not(target_arch = "aarch64"))]
+    (Opcode::Umax, &[I8, I8], &[I8], insert_opcode),
+    #[cfg(not(target_arch = "aarch64"))]
+    (Opcode::Umax, &[I16, I16], &[I16], insert_opcode),
+    #[cfg(not(target_arch = "aarch64"))]
+    (Opcode::Umax, &[I32, I32], &[I32], insert_opcode),
+    #[cfg(not(target_arch = "aarch64"))]
+    (Opcode::Umax, &[I64, I64], &[I64], insert_opcode),
+    #[cfg(not(any(target_arch = "x86_64", target_arch = "aarch64")))]
+    (Opcode::Umax, &[I128, I128], &[I128], insert_opcode),
     // Rotr
     (Opcode::Rotr, &[I8, I8], &[I8], insert_opcode),
     (Opcode::Rotr, &[I8, I16], &[I8], insert_opcode),
@@ -546,6 +612,96 @@ const OPCODE_SIGNATURES: &'static [(
     (Opcode::BxorNot, &[F32, F32], &[F32], insert_opcode),
     #[cfg(not(any(target_arch = "x86_64", target_arch = "aarch64")))]
     (Opcode::BxorNot, &[F64, F64], &[F64], insert_opcode),
+    // Bitrev
+    (Opcode::Bitrev, &[I8], &[I8], insert_opcode),
+    (Opcode::Bitrev, &[I16], &[I16], insert_opcode),
+    (Opcode::Bitrev, &[I32], &[I32], insert_opcode),
+    (Opcode::Bitrev, &[I64], &[I64], insert_opcode),
+    (Opcode::Bitrev, &[I128], &[I128], insert_opcode),
+    // Clz
+    (Opcode::Clz, &[I8], &[I8], insert_opcode),
+    (Opcode::Clz, &[I16], &[I16], insert_opcode),
+    (Opcode::Clz, &[I32], &[I32], insert_opcode),
+    (Opcode::Clz, &[I64], &[I64], insert_opcode),
+    (Opcode::Clz, &[I128], &[I128], insert_opcode),
+    // Cls
+    // cls not implemented in some backends:
+    //   x64: https://github.com/bytecodealliance/wasmtime/issues/5107
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Cls, &[I8], &[I8], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Cls, &[I16], &[I16], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Cls, &[I32], &[I32], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Cls, &[I64], &[I64], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Cls, &[I128], &[I128], insert_opcode),
+    // Ctz
+    (Opcode::Ctz, &[I8], &[I8], insert_opcode),
+    (Opcode::Ctz, &[I16], &[I16], insert_opcode),
+    (Opcode::Ctz, &[I32], &[I32], insert_opcode),
+    (Opcode::Ctz, &[I64], &[I64], insert_opcode),
+    (Opcode::Ctz, &[I128], &[I128], insert_opcode),
+    // Popcnt
+    (Opcode::Popcnt, &[I8], &[I8], insert_opcode),
+    (Opcode::Popcnt, &[I16], &[I16], insert_opcode),
+    (Opcode::Popcnt, &[I32], &[I32], insert_opcode),
+    (Opcode::Popcnt, &[I64], &[I64], insert_opcode),
+    (Opcode::Popcnt, &[I128], &[I128], insert_opcode),
+    // Bmask
+    // bmask not implemented in some backends:
+    //   x64: https://github.com/bytecodealliance/wasmtime/issues/5106
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I8], &[I8], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I16], &[I8], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I32], &[I8], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I64], &[I8], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I128], &[I8], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I8], &[I16], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I16], &[I16], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I32], &[I16], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I64], &[I16], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I128], &[I16], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I8], &[I32], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I16], &[I32], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I32], &[I32], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I64], &[I32], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I128], &[I32], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I8], &[I64], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I16], &[I64], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I32], &[I64], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I64], &[I64], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I128], &[I64], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I8], &[I128], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I16], &[I128], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I32], &[I128], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I64], &[I128], insert_opcode),
+    #[cfg(not(target_arch = "x86_64"))]
+    (Opcode::Bmask, &[I128], &[I128], insert_opcode),
     // Fadd
     (Opcode::Fadd, &[F32, F32], &[F32], insert_opcode),
     (Opcode::Fadd, &[F64, F64], &[F64], insert_opcode),