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s390x: implement vec_subc_u128 using overflowing_sub

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This commit is contained in:
Folkert de Vries 2025-08-20 18:08:51 +02:00
parent e1a1b1ded2
commit dfa95c6fa4
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1 changed files with 4 additions and 6 deletions
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10
library/stdarch/crates/core_arch/src/s390x/vector.rs
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@ -4678,11 +4678,9 @@ pub unsafe fn vec_subc_u128(
a: vector_unsigned_char,
b: vector_unsigned_char,
) -> vector_unsigned_char {
// FIXME(llvm) sadly this does not work https://github.com/llvm/llvm-project/issues/129608
// let a: u128 = transmute(a);
// let b: u128 = transmute(b);
// transmute(!a.overflowing_sub(b).1 as u128)
transmute(vscbiq(transmute(a), transmute(b)))
let a: u128 = transmute(a);
let b: u128 = transmute(b);
transmute(!a.overflowing_sub(b).1 as u128)
}
/// Vector Add Compute Carryout unsigned 128-bits
@ -4714,7 +4712,7 @@ pub unsafe fn vec_adde_u128(
let a: u128 = transmute(a);
let b: u128 = transmute(b);
let c: u128 = transmute(c);
// FIXME(llvm) sadly this does not work
// FIXME(llvm) https://github.com/llvm/llvm-project/pull/153557
// let (d, _carry) = a.carrying_add(b, c & 1 != 0);
// transmute(d)
transmute(vacq(a, b, c))