mirror of
https://github.com/rust-lang/rust.git
synced 2025-11-03 22:49:17 +00:00
531 lines
18 KiB
Rust
531 lines
18 KiB
Rust
use rustc_apfloat::ppc::DoubleDouble;
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use rustc_apfloat::{Category, Float, Round};
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use std::cmp::Ordering;
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#[test]
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fn ppc_double_double() {
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let test = DoubleDouble::ZERO;
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let expected = "0x0p+0".parse::<DoubleDouble>().unwrap();
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assert!(test.is_zero());
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assert!(!test.is_negative());
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assert!(test.bitwise_eq(expected));
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assert_eq!(0, test.to_bits());
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let test = -DoubleDouble::ZERO;
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let expected = "-0x0p+0".parse::<DoubleDouble>().unwrap();
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assert!(test.is_zero());
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assert!(test.is_negative());
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assert!(test.bitwise_eq(expected));
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assert_eq!(0x8000000000000000, test.to_bits());
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let test = "1.0".parse::<DoubleDouble>().unwrap();
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assert_eq!(0x3ff0000000000000, test.to_bits());
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// LDBL_MAX
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let test = "1.79769313486231580793728971405301e+308".parse::<DoubleDouble>().unwrap();
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assert_eq!(0x7c8ffffffffffffe_7fefffffffffffff, test.to_bits());
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// LDBL_MIN
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let test = "2.00416836000897277799610805135016e-292".parse::<DoubleDouble>().unwrap();
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assert_eq!(0x0000000000000000_0360000000000000, test.to_bits());
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}
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#[test]
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fn ppc_double_double_add_special() {
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let data = [
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// (1 + 0) + (-1 + 0) = Category::Zero
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(0x3ff0000000000000, 0xbff0000000000000, Category::Zero, Round::NearestTiesToEven),
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// LDBL_MAX + (1.1 >> (1023 - 106) + 0)) = Category::Infinity
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(
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0x7c8ffffffffffffe_7fefffffffffffff,
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0x7948000000000000,
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Category::Infinity,
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Round::NearestTiesToEven,
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),
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// FIXME: change the 4th 0x75effffffffffffe to 0x75efffffffffffff when
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// DoubleDouble's fallback is gone.
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// LDBL_MAX + (1.011111... >> (1023 - 106) + (1.1111111...0 >> (1023 -
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// 160))) = Category::Normal
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(
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0x7c8ffffffffffffe_7fefffffffffffff,
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0x75effffffffffffe_7947ffffffffffff,
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Category::Normal,
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Round::NearestTiesToEven,
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),
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// LDBL_MAX + (1.1 >> (1023 - 106) + 0)) = Category::Infinity
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(
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0x7c8ffffffffffffe_7fefffffffffffff,
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0x7c8ffffffffffffe_7fefffffffffffff,
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Category::Infinity,
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Round::NearestTiesToEven,
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),
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// NaN + (1 + 0) = Category::NaN
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(0x7ff8000000000000, 0x3ff0000000000000, Category::NaN, Round::NearestTiesToEven),
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];
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for &(op1, op2, expected, round) in &data {
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{
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let mut a1 = DoubleDouble::from_bits(op1);
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let a2 = DoubleDouble::from_bits(op2);
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a1 = a1.add_r(a2, round).value;
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assert_eq!(expected, a1.category(), "{:#x} + {:#x}", op1, op2);
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}
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{
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let a1 = DoubleDouble::from_bits(op1);
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let mut a2 = DoubleDouble::from_bits(op2);
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a2 = a2.add_r(a1, round).value;
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assert_eq!(expected, a2.category(), "{:#x} + {:#x}", op2, op1);
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}
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}
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}
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#[test]
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fn ppc_double_double_add() {
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let data = [
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// (1 + 0) + (1e-105 + 0) = (1 + 1e-105)
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(
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0x3ff0000000000000,
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0x3960000000000000,
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0x3960000000000000_3ff0000000000000,
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Round::NearestTiesToEven,
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),
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// (1 + 0) + (1e-106 + 0) = (1 + 1e-106)
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(
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0x3ff0000000000000,
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0x3950000000000000,
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0x3950000000000000_3ff0000000000000,
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Round::NearestTiesToEven,
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),
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// (1 + 1e-106) + (1e-106 + 0) = (1 + 1e-105)
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(
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0x3950000000000000_3ff0000000000000,
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0x3950000000000000,
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0x3960000000000000_3ff0000000000000,
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Round::NearestTiesToEven,
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),
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// (1 + 0) + (epsilon + 0) = (1 + epsilon)
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(
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0x3ff0000000000000,
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0x0000000000000001,
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0x0000000000000001_3ff0000000000000,
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Round::NearestTiesToEven,
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),
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// FIXME: change 0xf950000000000000 to 0xf940000000000000, when
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// DoubleDouble's fallback is gone.
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// (DBL_MAX - 1 << (1023 - 105)) + (1 << (1023 - 53) + 0) = DBL_MAX +
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// 1.11111... << (1023 - 52)
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(
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0xf950000000000000_7fefffffffffffff,
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0x7c90000000000000,
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0x7c8ffffffffffffe_7fefffffffffffff,
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Round::NearestTiesToEven,
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),
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// FIXME: change 0xf950000000000000 to 0xf940000000000000, when
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// DoubleDouble's fallback is gone.
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// (1 << (1023 - 53) + 0) + (DBL_MAX - 1 << (1023 - 105)) = DBL_MAX +
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// 1.11111... << (1023 - 52)
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(
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0x7c90000000000000,
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0xf950000000000000_7fefffffffffffff,
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0x7c8ffffffffffffe_7fefffffffffffff,
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Round::NearestTiesToEven,
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),
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];
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for &(op1, op2, expected, round) in &data {
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{
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let mut a1 = DoubleDouble::from_bits(op1);
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let a2 = DoubleDouble::from_bits(op2);
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a1 = a1.add_r(a2, round).value;
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assert_eq!(expected, a1.to_bits(), "{:#x} + {:#x}", op1, op2);
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}
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{
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let a1 = DoubleDouble::from_bits(op1);
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let mut a2 = DoubleDouble::from_bits(op2);
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a2 = a2.add_r(a1, round).value;
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assert_eq!(expected, a2.to_bits(), "{:#x} + {:#x}", op2, op1);
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}
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}
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}
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#[test]
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fn ppc_double_double_subtract() {
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let data = [
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// (1 + 0) - (-1e-105 + 0) = (1 + 1e-105)
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(
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0x3ff0000000000000,
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0xb960000000000000,
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0x3960000000000000_3ff0000000000000,
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Round::NearestTiesToEven,
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),
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// (1 + 0) - (-1e-106 + 0) = (1 + 1e-106)
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(
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0x3ff0000000000000,
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0xb950000000000000,
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0x3950000000000000_3ff0000000000000,
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Round::NearestTiesToEven,
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),
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];
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for &(op1, op2, expected, round) in &data {
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let mut a1 = DoubleDouble::from_bits(op1);
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let a2 = DoubleDouble::from_bits(op2);
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a1 = a1.sub_r(a2, round).value;
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assert_eq!(expected, a1.to_bits(), "{:#x} - {:#x}", op1, op2);
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}
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}
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#[test]
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fn ppc_double_double_multiply_special() {
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let data = [
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// Category::NaN * Category::NaN = Category::NaN
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(0x7ff8000000000000, 0x7ff8000000000000, Category::NaN, Round::NearestTiesToEven),
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// Category::NaN * Category::Zero = Category::NaN
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(0x7ff8000000000000, 0, Category::NaN, Round::NearestTiesToEven),
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// Category::NaN * Category::Infinity = Category::NaN
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(0x7ff8000000000000, 0x7ff0000000000000, Category::NaN, Round::NearestTiesToEven),
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// Category::NaN * Category::Normal = Category::NaN
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(0x7ff8000000000000, 0x3ff0000000000000, Category::NaN, Round::NearestTiesToEven),
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// Category::Infinity * Category::Infinity = Category::Infinity
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(0x7ff0000000000000, 0x7ff0000000000000, Category::Infinity, Round::NearestTiesToEven),
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// Category::Infinity * Category::Zero = Category::NaN
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(0x7ff0000000000000, 0, Category::NaN, Round::NearestTiesToEven),
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// Category::Infinity * Category::Normal = Category::Infinity
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(0x7ff0000000000000, 0x3ff0000000000000, Category::Infinity, Round::NearestTiesToEven),
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// Category::Zero * Category::Zero = Category::Zero
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(0, 0, Category::Zero, Round::NearestTiesToEven),
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// Category::Zero * Category::Normal = Category::Zero
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(0, 0x3ff0000000000000, Category::Zero, Round::NearestTiesToEven),
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];
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for &(op1, op2, expected, round) in &data {
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{
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let mut a1 = DoubleDouble::from_bits(op1);
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let a2 = DoubleDouble::from_bits(op2);
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a1 = a1.mul_r(a2, round).value;
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assert_eq!(expected, a1.category(), "{:#x} * {:#x}", op1, op2);
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}
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{
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let a1 = DoubleDouble::from_bits(op1);
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let mut a2 = DoubleDouble::from_bits(op2);
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a2 = a2.mul_r(a1, round).value;
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assert_eq!(expected, a2.category(), "{:#x} * {:#x}", op2, op1);
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}
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}
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}
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#[test]
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fn ppc_double_double_multiply() {
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let data = [
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// 1/3 * 3 = 1.0
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(
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0x3c75555555555556_3fd5555555555555,
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0x4008000000000000,
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0x3ff0000000000000,
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Round::NearestTiesToEven,
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),
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// (1 + epsilon) * (1 + 0) = Category::Zero
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(
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0x0000000000000001_3ff0000000000000,
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0x3ff0000000000000,
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0x0000000000000001_3ff0000000000000,
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Round::NearestTiesToEven,
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),
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// (1 + epsilon) * (1 + epsilon) = 1 + 2 * epsilon
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(
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0x0000000000000001_3ff0000000000000,
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0x0000000000000001_3ff0000000000000,
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0x0000000000000002_3ff0000000000000,
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Round::NearestTiesToEven,
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),
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// -(1 + epsilon) * (1 + epsilon) = -1
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(
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0x0000000000000001_bff0000000000000,
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0x0000000000000001_3ff0000000000000,
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0xbff0000000000000,
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Round::NearestTiesToEven,
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),
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// (0.5 + 0) * (1 + 2 * epsilon) = 0.5 + epsilon
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(
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0x3fe0000000000000,
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0x0000000000000002_3ff0000000000000,
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0x0000000000000001_3fe0000000000000,
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Round::NearestTiesToEven,
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),
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// (0.5 + 0) * (1 + epsilon) = 0.5
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(
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0x3fe0000000000000,
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0x0000000000000001_3ff0000000000000,
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0x3fe0000000000000,
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Round::NearestTiesToEven,
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),
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// __LDBL_MAX__ * (1 + 1 << 106) = inf
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(
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0x7c8ffffffffffffe_7fefffffffffffff,
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0x3950000000000000_3ff0000000000000,
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0x7ff0000000000000,
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Round::NearestTiesToEven,
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),
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// __LDBL_MAX__ * (1 + 1 << 107) > __LDBL_MAX__, but not inf, yes =_=|||
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(
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0x7c8ffffffffffffe_7fefffffffffffff,
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0x3940000000000000_3ff0000000000000,
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0x7c8fffffffffffff_7fefffffffffffff,
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Round::NearestTiesToEven,
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),
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// __LDBL_MAX__ * (1 + 1 << 108) = __LDBL_MAX__
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(
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0x7c8ffffffffffffe_7fefffffffffffff,
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0x3930000000000000_3ff0000000000000,
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0x7c8ffffffffffffe_7fefffffffffffff,
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Round::NearestTiesToEven,
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),
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];
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for &(op1, op2, expected, round) in &data {
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{
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let mut a1 = DoubleDouble::from_bits(op1);
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let a2 = DoubleDouble::from_bits(op2);
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a1 = a1.mul_r(a2, round).value;
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assert_eq!(expected, a1.to_bits(), "{:#x} * {:#x}", op1, op2);
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}
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{
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let a1 = DoubleDouble::from_bits(op1);
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let mut a2 = DoubleDouble::from_bits(op2);
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a2 = a2.mul_r(a1, round).value;
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assert_eq!(expected, a2.to_bits(), "{:#x} * {:#x}", op2, op1);
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}
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}
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}
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#[test]
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fn ppc_double_double_divide() {
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// FIXME: Only a sanity check for now. Add more edge cases when the
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// double-double algorithm is implemented.
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let data = [
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// 1 / 3 = 1/3
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(
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0x3ff0000000000000,
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0x4008000000000000,
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0x3c75555555555556_3fd5555555555555,
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Round::NearestTiesToEven,
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),
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];
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for &(op1, op2, expected, round) in &data {
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let mut a1 = DoubleDouble::from_bits(op1);
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let a2 = DoubleDouble::from_bits(op2);
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a1 = a1.div_r(a2, round).value;
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assert_eq!(expected, a1.to_bits(), "{:#x} / {:#x}", op1, op2);
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}
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}
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#[test]
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fn ppc_double_double_remainder() {
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let data = [
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// ieee_rem(3.0 + 3.0 << 53, 1.25 + 1.25 << 53) = (0.5 + 0.5 << 53)
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(
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0x3cb8000000000000_4008000000000000,
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0x3ca4000000000000_3ff4000000000000,
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0x3c90000000000000_3fe0000000000000,
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),
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// ieee_rem(3.0 + 3.0 << 53, 1.75 + 1.75 << 53) = (-0.5 - 0.5 << 53)
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(
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0x3cb8000000000000_4008000000000000,
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0x3cac000000000000_3ffc000000000000,
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0xbc90000000000000_bfe0000000000000,
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),
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];
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for &(op1, op2, expected) in &data {
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let a1 = DoubleDouble::from_bits(op1);
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let a2 = DoubleDouble::from_bits(op2);
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let result = a1.ieee_rem(a2).value;
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assert_eq!(expected, result.to_bits(), "ieee_rem({:#x}, {:#x})", op1, op2);
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}
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}
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#[test]
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fn ppc_double_double_mod() {
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let data = [
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// mod(3.0 + 3.0 << 53, 1.25 + 1.25 << 53) = (0.5 + 0.5 << 53)
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(
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0x3cb8000000000000_4008000000000000,
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0x3ca4000000000000_3ff4000000000000,
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0x3c90000000000000_3fe0000000000000,
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),
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// mod(3.0 + 3.0 << 53, 1.75 + 1.75 << 53) = (1.25 + 1.25 << 53)
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// 0xbc98000000000000 doesn't seem right, but it's what we currently have.
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// FIXME: investigate
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(
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0x3cb8000000000000_4008000000000000,
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0x3cac000000000000_3ffc000000000000,
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0xbc98000000000000_3ff4000000000001,
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),
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];
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for &(op1, op2, expected) in &data {
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let a1 = DoubleDouble::from_bits(op1);
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let a2 = DoubleDouble::from_bits(op2);
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let r = (a1 % a2).value;
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assert_eq!(expected, r.to_bits(), "fmod({:#x}, {:#x})", op1, op2);
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}
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}
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#[test]
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fn ppc_double_double_fma() {
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// Sanity check for now.
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let mut a = "2".parse::<DoubleDouble>().unwrap();
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a = a.mul_add("3".parse::<DoubleDouble>().unwrap(), "4".parse::<DoubleDouble>().unwrap()).value;
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assert_eq!(Some(Ordering::Equal), "10".parse::<DoubleDouble>().unwrap().partial_cmp(&a));
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}
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#[test]
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fn ppc_double_double_round_to_integral() {
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{
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let a = "1.5".parse::<DoubleDouble>().unwrap();
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let a = a.round_to_integral(Round::NearestTiesToEven).value;
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assert_eq!(Some(Ordering::Equal), "2".parse::<DoubleDouble>().unwrap().partial_cmp(&a));
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}
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{
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let a = "2.5".parse::<DoubleDouble>().unwrap();
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let a = a.round_to_integral(Round::NearestTiesToEven).value;
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assert_eq!(Some(Ordering::Equal), "2".parse::<DoubleDouble>().unwrap().partial_cmp(&a));
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}
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}
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#[test]
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fn ppc_double_double_compare() {
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let data = [
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// (1 + 0) = (1 + 0)
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(0x3ff0000000000000, 0x3ff0000000000000, Some(Ordering::Equal)),
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// (1 + 0) < (1.00...1 + 0)
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(0x3ff0000000000000, 0x3ff0000000000001, Some(Ordering::Less)),
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// (1.00...1 + 0) > (1 + 0)
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(0x3ff0000000000001, 0x3ff0000000000000, Some(Ordering::Greater)),
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// (1 + 0) < (1 + epsilon)
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(0x3ff0000000000000, 0x0000000000000001_3ff0000000000001, Some(Ordering::Less)),
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// NaN != NaN
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(0x7ff8000000000000, 0x7ff8000000000000, None),
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// (1 + 0) != NaN
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(0x3ff0000000000000, 0x7ff8000000000000, None),
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// Inf = Inf
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(0x7ff0000000000000, 0x7ff0000000000000, Some(Ordering::Equal)),
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];
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for &(op1, op2, expected) in &data {
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let a1 = DoubleDouble::from_bits(op1);
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let a2 = DoubleDouble::from_bits(op2);
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assert_eq!(expected, a1.partial_cmp(&a2), "compare({:#x}, {:#x})", op1, op2,);
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}
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}
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#[test]
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fn ppc_double_double_bitwise_eq() {
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let data = [
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// (1 + 0) = (1 + 0)
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(0x3ff0000000000000, 0x3ff0000000000000, true),
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// (1 + 0) != (1.00...1 + 0)
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(0x3ff0000000000000, 0x3ff0000000000001, false),
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// NaN = NaN
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(0x7ff8000000000000, 0x7ff8000000000000, true),
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// NaN != NaN with a different bit pattern
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(0x7ff8000000000000, 0x3ff0000000000000_7ff8000000000000, false),
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// Inf = Inf
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(0x7ff0000000000000, 0x7ff0000000000000, true),
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];
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for &(op1, op2, expected) in &data {
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|
let a1 = DoubleDouble::from_bits(op1);
|
|
let a2 = DoubleDouble::from_bits(op2);
|
|
assert_eq!(expected, a1.bitwise_eq(a2), "{:#x} = {:#x}", op1, op2);
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn ppc_double_double_change_sign() {
|
|
let float = DoubleDouble::from_bits(0xbcb0000000000000_400f000000000000);
|
|
{
|
|
let actual = float.copy_sign("1".parse::<DoubleDouble>().unwrap());
|
|
assert_eq!(0xbcb0000000000000_400f000000000000, actual.to_bits());
|
|
}
|
|
{
|
|
let actual = float.copy_sign("-1".parse::<DoubleDouble>().unwrap());
|
|
assert_eq!(0x3cb0000000000000_c00f000000000000, actual.to_bits());
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn ppc_double_double_factories() {
|
|
assert_eq!(0, DoubleDouble::ZERO.to_bits());
|
|
assert_eq!(0x7c8ffffffffffffe_7fefffffffffffff, DoubleDouble::largest().to_bits());
|
|
assert_eq!(0x0000000000000001, DoubleDouble::SMALLEST.to_bits());
|
|
assert_eq!(0x0360000000000000, DoubleDouble::smallest_normalized().to_bits());
|
|
assert_eq!(0x0000000000000000_8000000000000000, (-DoubleDouble::ZERO).to_bits());
|
|
assert_eq!(0xfc8ffffffffffffe_ffefffffffffffff, (-DoubleDouble::largest()).to_bits());
|
|
assert_eq!(0x0000000000000000_8000000000000001, (-DoubleDouble::SMALLEST).to_bits());
|
|
assert_eq!(
|
|
0x0000000000000000_8360000000000000,
|
|
(-DoubleDouble::smallest_normalized()).to_bits()
|
|
);
|
|
assert!(DoubleDouble::SMALLEST.is_smallest());
|
|
assert!(DoubleDouble::largest().is_largest());
|
|
}
|
|
|
|
#[test]
|
|
fn ppc_double_double_is_denormal() {
|
|
assert!(DoubleDouble::SMALLEST.is_denormal());
|
|
assert!(!DoubleDouble::largest().is_denormal());
|
|
assert!(!DoubleDouble::smallest_normalized().is_denormal());
|
|
{
|
|
// (4 + 3) is not normalized
|
|
let data = 0x4008000000000000_4010000000000000;
|
|
assert!(DoubleDouble::from_bits(data).is_denormal());
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn ppc_double_double_exact_inverse() {
|
|
assert!(
|
|
"2.0"
|
|
.parse::<DoubleDouble>()
|
|
.unwrap()
|
|
.get_exact_inverse()
|
|
.unwrap()
|
|
.bitwise_eq("0.5".parse::<DoubleDouble>().unwrap())
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn ppc_double_double_scalbn() {
|
|
// 3.0 + 3.0 << 53
|
|
let input = 0x3cb8000000000000_4008000000000000;
|
|
let result = DoubleDouble::from_bits(input).scalbn(1);
|
|
// 6.0 + 6.0 << 53
|
|
assert_eq!(0x3cc8000000000000_4018000000000000, result.to_bits());
|
|
}
|
|
|
|
#[test]
|
|
fn ppc_double_double_frexp() {
|
|
// 3.0 + 3.0 << 53
|
|
let input = 0x3cb8000000000000_4008000000000000;
|
|
let mut exp = 0;
|
|
// 0.75 + 0.75 << 53
|
|
let result = DoubleDouble::from_bits(input).frexp(&mut exp);
|
|
assert_eq!(2, exp);
|
|
assert_eq!(0x3c98000000000000_3fe8000000000000, result.to_bits());
|
|
}
|