mirror of
https://github.com/rust-lang/rust.git
synced 2024-11-02 07:22:42 +00:00
50 lines
1.7 KiB
Rust
50 lines
1.7 KiB
Rust
// compile-flags: -C opt-level=3 -C target-cpu=x86-64-v3
|
|
// no-system-llvm
|
|
// only-x86_64
|
|
// ignore-debug (the extra assertions get in the way)
|
|
|
|
#![crate_type = "lib"]
|
|
#![feature(array_zip)]
|
|
|
|
// CHECK-LABEL: @short_integer_map
|
|
#[no_mangle]
|
|
pub fn short_integer_map(x: [u32; 8]) -> [u32; 8] {
|
|
// CHECK: load <8 x i32>
|
|
// CHECK: shl <8 x i32>
|
|
// CHECK: or <8 x i32>
|
|
// CHECK: store <8 x i32>
|
|
x.map(|x| 2 * x + 1)
|
|
}
|
|
|
|
// CHECK-LABEL: @short_integer_zip_map
|
|
#[no_mangle]
|
|
pub fn short_integer_zip_map(x: [u32; 8], y: [u32; 8]) -> [u32; 8] {
|
|
// CHECK: %[[A:.+]] = load <8 x i32>
|
|
// CHECK: %[[B:.+]] = load <8 x i32>
|
|
// CHECK: sub <8 x i32> %[[B]], %[[A]]
|
|
// CHECK: store <8 x i32>
|
|
x.zip(y).map(|(x, y)| x - y)
|
|
}
|
|
|
|
// This test is checking that LLVM can SRoA away a bunch of the overhead,
|
|
// like fully moving the iterators to registers. Notably, previous implementations
|
|
// of `map` ended up `alloca`ing the whole `array::IntoIterator`, meaning both a
|
|
// hard-to-eliminate `memcpy` and that the iteration counts needed to be written
|
|
// out to stack every iteration, even for infallible operations on `Copy` types.
|
|
//
|
|
// This is still imperfect, as there's more copies than would be ideal,
|
|
// but hopefully work like #103830 will improve that in future,
|
|
// and update this test to be stricter.
|
|
//
|
|
// CHECK-LABEL: @long_integer_map
|
|
#[no_mangle]
|
|
pub fn long_integer_map(x: [u32; 512]) -> [u32; 512] {
|
|
// CHECK: start:
|
|
// CHECK-NEXT: alloca [512 x i32]
|
|
// CHECK-NEXT: alloca %"core::mem::manually_drop::ManuallyDrop<[u32; 512]>"
|
|
// CHECK-NOT: alloca
|
|
// CHECK: mul <{{[0-9]+}} x i32>
|
|
// CHECK: add <{{[0-9]+}} x i32>
|
|
x.map(|x| 13 * x + 7)
|
|
}
|