message: Fix underflow in subtraction on global.get with float-type global.
diff: @@ -2978,8 +2978,7 @@ impl FunctionCodeGenerator<CodegenError> for X64FunctionCode {
  );
  let ty = type_to_wp_type(module_info.globals[local_index].desc.ty);
  if ty.is_float() {
  - self.fp_stack
  - .push(FloatValue::new(self.value_stack.len() - 1));
  + self.fp_stack.push(FloatValue::new(self.value_stack.len()));
  }
  self.machine.acquire_locations(
  a,
  @@ -3003,8 +3002,7 @@ impl FunctionCodeGenerator<CodegenError> for X64FunctionCode {
  );
  let ty = type_to_wp_type(module_info.imported_globals[import_index].1.ty);
  if ty.is_float() {
  - self.fp_stack
  - .push(FloatValue::new(self.value_stack.len() - 1));
  + self.fp_stack.push(FloatValue::new(self.value_stack.len()));
  }
  self.machine.acquire_locations(
  a,
  