Fix abi for checked multiplication

Author: bjorn3

example/std_example.rs

@@ -58,6 +58,7 @@ fn main() {
     assert_eq!(0b0000000000000000000000000010000000000000000000000000000000000000_0000000000000000000000000000000000001000000000000000000010000000u128.trailing_zeros(), 7);
     assert_eq!(core::intrinsics::saturating_sub(0, -170141183460469231731687303715884105728i128), 170141183460469231731687303715884105727i128);
 
+    std::hint::black_box(std::hint::black_box(7571400400375753350092698930310845914i128) * 10);
     assert!(0i128.checked_div(2i128).is_some());
     assert!(0u128.checked_div(2u128).is_some());
     assert_eq!(1u128 + 2, 3);

src/codegen_i128.rs

@@ -46,7 +46,7 @@ pub(crate) fn maybe_codegen<'tcx>(
                 let lhs = lhs.load_scalar(fx);
                 let rhs = rhs.load_scalar(fx);
                 let oflow_ptr = oflow.to_ptr().get_addr(fx);
-                let res = fx.lib_call(
+                let res = fx.lib_call_unadjusted(
                     "__muloti4",
                     vec![
                         AbiParam::new(types::I128),

src/compiler_builtins.rs

@@ -39,6 +39,7 @@ builtin_functions! {
 
     // integers
     fn __multi3(a: i128, b: i128) -> i128;
+    fn __muloti4(n: i128, d: i128, oflow: &mut i32) -> i128;
     fn __udivti3(n: u128, d: u128) -> u128;
     fn __divti3(n: i128, d: i128) -> i128;
     fn __umodti3(n: u128, d: u128) -> u128;