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Use load-store instead of memcpy for short integer arrays

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Scott McMurray 2023-05-26 03:32:22 -07:00
parent cce0b52e7b
commit e1b020df9f
8 changed files with 136 additions and 16 deletions
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35
tests/codegen/array-codegen.rs Normal file
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// compile-flags: -O -C no-prepopulate-passes
// min-llvm-version: 15.0 (for opaque pointers)
#![crate_type = "lib"]
// CHECK-LABEL: @array_load
#[no_mangle]
pub fn array_load(a: &[u8; 4]) -> [u8; 4] {
// CHECK: %0 = alloca [4 x i8], align 1
// CHECK: %[[TEMP1:.+]] = load <4 x i8>, ptr %a, align 1
// CHECK: store <4 x i8> %[[TEMP1]], ptr %0, align 1
// CHECK: %[[TEMP2:.+]] = load i32, ptr %0, align 1
// CHECK: ret i32 %[[TEMP2]]
*a
}
// CHECK-LABEL: @array_store
#[no_mangle]
pub fn array_store(a: [u8; 4], p: &mut [u8; 4]) {
// CHECK: %a = alloca [4 x i8]
// CHECK: %[[TEMP:.+]] = load <4 x i8>, ptr %a, align 1
// CHECK-NEXT: store <4 x i8> %[[TEMP]], ptr %p, align 1
*p = a;
}
// CHECK-LABEL: @array_copy
#[no_mangle]
pub fn array_copy(a: &[u8; 4], p: &mut [u8; 4]) {
// CHECK: %[[LOCAL:.+]] = alloca [4 x i8], align 1
// CHECK: %[[TEMP1:.+]] = load <4 x i8>, ptr %a, align 1
// CHECK: store <4 x i8> %[[TEMP1]], ptr %[[LOCAL]], align 1
// CHECK: %[[TEMP2:.+]] = load <4 x i8>, ptr %[[LOCAL]], align 1
// CHECK: store <4 x i8> %[[TEMP2]], ptr %p, align 1
*p = *a;
}