0601f0c66d
This is just one part of the MCP, but it's the one that IMHO removes the most noise from the standard library code. Seems net simpler this way, since MIR already supported heterogeneous shifts anyway, and thus it's not more work for backends than before.
150 lines
6.5 KiB
Rust
150 lines
6.5 KiB
Rust
#![feature(core_intrinsics)]
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use std::intrinsics;
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// The documentation of `unchecked_shl` states that it:
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//
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// Performs an unchecked left shift, resulting in undefined behavior when
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// y < 0 or y >= N, where N is the width of T in bits.
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//
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// So we check this for a few `y`.
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// unsigned types:
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const SHL_U8: u8 = unsafe { intrinsics::unchecked_shl(5_u8, 8) };
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//~^ ERROR evaluation of constant value failed
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const SHL_U16: u16 = unsafe { intrinsics::unchecked_shl(5_u16, 16) };
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//~^ ERROR evaluation of constant value failed
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const SHL_U32: u32 = unsafe { intrinsics::unchecked_shl(5_u32, 32) };
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//~^ ERROR evaluation of constant value failed
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const SHL_U64: u64 = unsafe { intrinsics::unchecked_shl(5_u64, 64) };
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//~^ ERROR evaluation of constant value failed
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const SHL_U128: u128 = unsafe { intrinsics::unchecked_shl(5_u128, 128) };
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//~^ ERROR evaluation of constant value failed
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// signed types:
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const SHL_I8: i8 = unsafe { intrinsics::unchecked_shl(5_i8, 8) };
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//~^ ERROR evaluation of constant value failed
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const SHL_I16: i16 = unsafe { intrinsics::unchecked_shl(5_i16, 16) };
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//~^ ERROR evaluation of constant value failed
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const SHL_I32: i32 = unsafe { intrinsics::unchecked_shl(5_i32, 32) };
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//~^ ERROR evaluation of constant value failed
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const SHL_I64: i64 = unsafe { intrinsics::unchecked_shl(5_i64, 64) };
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//~^ ERROR evaluation of constant value failed
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const SHL_I128: i128 = unsafe { intrinsics::unchecked_shl(5_i128, 128) };
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//~^ ERROR evaluation of constant value failed
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// and make sure we capture y < 0:
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const SHL_I8_NEG: i8 = unsafe { intrinsics::unchecked_shl(5_i8, -1) };
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//~^ ERROR evaluation of constant value failed
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const SHL_I16_NEG: i16 = unsafe { intrinsics::unchecked_shl(5_i16, -1) };
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//~^ ERROR evaluation of constant value failed
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const SHL_I32_NEG: i32 = unsafe { intrinsics::unchecked_shl(5_i32, -1) };
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//~^ ERROR evaluation of constant value failed
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const SHL_I64_NEG: i64 = unsafe { intrinsics::unchecked_shl(5_i64, -1) };
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//~^ ERROR evaluation of constant value failed
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const SHL_I128_NEG: i128 = unsafe { intrinsics::unchecked_shl(5_i128, -1) };
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//~^ ERROR evaluation of constant value failed
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// and that there's no special relation to the value -1 by picking some
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// negative values at random:
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const SHL_I8_NEG_RANDOM: i8 = unsafe { intrinsics::unchecked_shl(5_i8, -6) };
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//~^ ERROR evaluation of constant value failed
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const SHL_I16_NEG_RANDOM: i16 = unsafe { intrinsics::unchecked_shl(5_i16, -13) };
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//~^ ERROR evaluation of constant value failed
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const SHL_I32_NEG_RANDOM: i32 = unsafe { intrinsics::unchecked_shl(5_i32, -25) };
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//~^ ERROR evaluation of constant value failed
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const SHL_I64_NEG_RANDOM: i64 = unsafe { intrinsics::unchecked_shl(5_i64, -30) };
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//~^ ERROR evaluation of constant value failed
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const SHL_I128_NEG_RANDOM: i128 = unsafe { intrinsics::unchecked_shl(5_i128, -93) };
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//~^ ERROR evaluation of constant value failed
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// Repeat it all over for `unchecked_shr`
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// unsigned types:
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const SHR_U8: u8 = unsafe { intrinsics::unchecked_shr(5_u8, 8) };
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//~^ ERROR evaluation of constant value failed
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const SHR_U16: u16 = unsafe { intrinsics::unchecked_shr(5_u16, 16) };
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//~^ ERROR evaluation of constant value failed
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const SHR_U32: u32 = unsafe { intrinsics::unchecked_shr(5_u32, 32) };
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//~^ ERROR evaluation of constant value failed
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const SHR_U64: u64 = unsafe { intrinsics::unchecked_shr(5_u64, 64) };
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//~^ ERROR evaluation of constant value failed
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const SHR_U128: u128 = unsafe { intrinsics::unchecked_shr(5_u128, 128) };
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//~^ ERROR evaluation of constant value failed
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// signed types:
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const SHR_I8: i8 = unsafe { intrinsics::unchecked_shr(5_i8, 8) };
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//~^ ERROR evaluation of constant value failed
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const SHR_I16: i16 = unsafe { intrinsics::unchecked_shr(5_i16, 16) };
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//~^ ERROR evaluation of constant value failed
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const SHR_I32: i32 = unsafe { intrinsics::unchecked_shr(5_i32, 32) };
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//~^ ERROR evaluation of constant value failed
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const SHR_I64: i64 = unsafe { intrinsics::unchecked_shr(5_i64, 64) };
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//~^ ERROR evaluation of constant value failed
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const SHR_I128: i128 = unsafe { intrinsics::unchecked_shr(5_i128, 128) };
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//~^ ERROR evaluation of constant value failed
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// and make sure we capture y < 0:
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const SHR_I8_NEG: i8 = unsafe { intrinsics::unchecked_shr(5_i8, -1) };
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//~^ ERROR evaluation of constant value failed
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const SHR_I16_NEG: i16 = unsafe { intrinsics::unchecked_shr(5_i16, -1) };
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//~^ ERROR evaluation of constant value failed
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const SHR_I32_NEG: i32 = unsafe { intrinsics::unchecked_shr(5_i32, -1) };
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//~^ ERROR evaluation of constant value failed
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const SHR_I64_NEG: i64 = unsafe { intrinsics::unchecked_shr(5_i64, -1) };
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//~^ ERROR evaluation of constant value failed
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const SHR_I128_NEG: i128 = unsafe { intrinsics::unchecked_shr(5_i128, -1) };
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//~^ ERROR evaluation of constant value failed
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// and that there's no special relation to the value -1 by picking some
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// negative values at random:
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const SHR_I8_NEG_RANDOM: i8 = unsafe { intrinsics::unchecked_shr(5_i8, -6) };
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//~^ ERROR evaluation of constant value failed
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const SHR_I16_NEG_RANDOM: i16 = unsafe { intrinsics::unchecked_shr(5_i16, -13) };
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//~^ ERROR evaluation of constant value failed
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const SHR_I32_NEG_RANDOM: i32 = unsafe { intrinsics::unchecked_shr(5_i32, -25) };
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//~^ ERROR evaluation of constant value failed
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const SHR_I64_NEG_RANDOM: i64 = unsafe { intrinsics::unchecked_shr(5_i64, -30) };
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//~^ ERROR evaluation of constant value failed
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const SHR_I128_NEG_RANDOM: i128 = unsafe { intrinsics::unchecked_shr(5_i128, -93) };
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//~^ ERROR evaluation of constant value failed
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// Other arithmetic functions:
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const _: u16 = unsafe { std::intrinsics::unchecked_add(40000u16, 30000) };
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//~^ ERROR evaluation of constant value failed
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const _: u32 = unsafe { std::intrinsics::unchecked_sub(14u32, 22) };
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//~^ ERROR evaluation of constant value failed
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const _: u16 = unsafe { std::intrinsics::unchecked_mul(300u16, 250u16) };
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//~^ ERROR evaluation of constant value failed
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const _: i32 = unsafe { std::intrinsics::unchecked_div(1, 0) };
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//~^ ERROR evaluation of constant value failed
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const _: i32 = unsafe { std::intrinsics::unchecked_div(i32::MIN, -1) };
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//~^ ERROR evaluation of constant value failed
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const _: i32 = unsafe { std::intrinsics::unchecked_rem(1, 0) };
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//~^ ERROR evaluation of constant value failed
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const _: i32 = unsafe { std::intrinsics::unchecked_rem(i32::MIN, -1) };
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//~^ ERROR evaluation of constant value failed
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// capture fault with zero value
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const _: u32 = unsafe { std::intrinsics::ctlz_nonzero(0) };
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//~^ ERROR evaluation of constant value failed
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const _: u32 = unsafe { std::intrinsics::cttz_nonzero(0) };
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//~^ ERROR evaluation of constant value failed
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fn main() {}
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