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unchecked_shifts.rs
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//@ revisions: LLVM18 LLVM19PLUS
//@ compile-flags: -Copt-level=3 -C no-prepopulate-passes
//@[LLVM18] exact-llvm-major-version: 18
//@[LLVM19PLUS] min-llvm-version: 19
// This runs mir-opts to inline the standard library call, but doesn't run LLVM
// optimizations so it doesn't need to worry about them adding more flags.
#![crate_type = "lib"]
#![feature(unchecked_shifts)]
#![feature(core_intrinsics)]
// CHECK-LABEL: @unchecked_shl_unsigned_same
#[no_mangle]
pub unsafe fn unchecked_shl_unsigned_same(a: u32, b: u32) -> u32 {
// CHECK-NOT: assume
// CHECK-NOT: and i32
// CHECK: shl i32 %a, %b
// CHECK-NOT: and i32
a.unchecked_shl(b)
}
// CHECK-LABEL: @unchecked_shl_unsigned_smaller
#[no_mangle]
pub unsafe fn unchecked_shl_unsigned_smaller(a: u16, b: u32) -> u16 {
// CHECK-NOT: assume
// LLVM18: %[[TRUNC:.+]] = trunc i32 %b to i16
// LLVM19PLUS: %[[TRUNC:.+]] = trunc nuw i32 %b to i16
// CHECK: shl i16 %a, %[[TRUNC]]
a.unchecked_shl(b)
}
// CHECK-LABEL: @unchecked_shl_unsigned_bigger
#[no_mangle]
pub unsafe fn unchecked_shl_unsigned_bigger(a: u64, b: u32) -> u64 {
// CHECK-NOT: assume
// CHECK: %[[EXT:.+]] = zext i32 %b to i64
// CHECK: shl i64 %a, %[[EXT]]
a.unchecked_shl(b)
}
// CHECK-LABEL: @unchecked_shr_signed_same
#[no_mangle]
pub unsafe fn unchecked_shr_signed_same(a: i32, b: u32) -> i32 {
// CHECK-NOT: assume
// CHECK-NOT: and i32
// CHECK: ashr i32 %a, %b
// CHECK-NOT: and i32
a.unchecked_shr(b)
}
// CHECK-LABEL: @unchecked_shr_signed_smaller
#[no_mangle]
pub unsafe fn unchecked_shr_signed_smaller(a: i16, b: u32) -> i16 {
// CHECK-NOT: assume
// LLVM18: %[[TRUNC:.+]] = trunc i32 %b to i16
// LLVM19PLUS: %[[TRUNC:.+]] = trunc nuw i32 %b to i16
// CHECK: ashr i16 %a, %[[TRUNC]]
a.unchecked_shr(b)
}
// CHECK-LABEL: @unchecked_shr_signed_bigger
#[no_mangle]
pub unsafe fn unchecked_shr_signed_bigger(a: i64, b: u32) -> i64 {
// CHECK-NOT: assume
// CHECK: %[[EXT:.+]] = zext i32 %b to i64
// CHECK: ashr i64 %a, %[[EXT]]
a.unchecked_shr(b)
}
// CHECK-LABEL: @unchecked_shr_u128_i8
#[no_mangle]
pub unsafe fn unchecked_shr_u128_i8(a: u128, b: i8) -> u128 {
// CHECK-NOT: assume
// CHECK: %[[EXT:.+]] = zext i8 %b to i128
// CHECK: lshr i128 %a, %[[EXT]]
std::intrinsics::unchecked_shr(a, b)
}
// CHECK-LABEL: @unchecked_shl_i128_u8
#[no_mangle]
pub unsafe fn unchecked_shl_i128_u8(a: i128, b: u8) -> i128 {
// CHECK-NOT: assume
// CHECK: %[[EXT:.+]] = zext i8 %b to i128
// CHECK: shl i128 %a, %[[EXT]]
std::intrinsics::unchecked_shl(a, b)
}
// CHECK-LABEL: @unchecked_shl_u8_i128
#[no_mangle]
pub unsafe fn unchecked_shl_u8_i128(a: u8, b: i128) -> u8 {
// CHECK-NOT: assume
// LLVM18: %[[TRUNC:.+]] = trunc i128 %b to i8
// LLVM19PLUS: %[[TRUNC:.+]] = trunc nuw i128 %b to i8
// CHECK: shl i8 %a, %[[TRUNC]]
std::intrinsics::unchecked_shl(a, b)
}
// CHECK-LABEL: @unchecked_shr_i8_u128
#[no_mangle]
pub unsafe fn unchecked_shr_i8_u128(a: i8, b: u128) -> i8 {
// CHECK-NOT: assume
// LLVM18: %[[TRUNC:.+]] = trunc i128 %b to i8
// LLVM19PLUS: %[[TRUNC:.+]] = trunc nuw i128 %b to i8
// CHECK: ashr i8 %a, %[[TRUNC]]
std::intrinsics::unchecked_shr(a, b)
}