duckstation/dep/biscuit/include/biscuit/vector.hpp

89 lines
3.1 KiB
C++

#pragma once
#include <cstdint>
// Source file for anything specific to the RISC-V vector extension.
namespace biscuit {
/// Describes whether or not an instruction should make use of the mask vector.
enum class VecMask : uint32_t {
Yes = 0,
No = 1,
};
/// Describes the selected element width.
enum class SEW : uint32_t {
E8 = 0b000, // 8-bit vector elements
E16 = 0b001, // 16-bit vector elements
E32 = 0b010, // 32-bit vector elements
E64 = 0b011, // 64-bit vector elements
E128 = 0b100, // 128-bit vector elements
E256 = 0b101, // 256-bit vector elements
E512 = 0b110, // 512-bit vector elements
E1024 = 0b111, // 1024-bit vector elements
};
/// Describes the selected register group multiplier.
enum class LMUL : uint32_t {
M1 = 0b000, // Group of one vector
M2 = 0b001, // Groups of two vectors
M4 = 0b010, // Groups of four vectors
M8 = 0b011, // Groups of eight vectors
MF8 = 0b101, // Fractional vector group (1/8)
MF4 = 0b110, // Fractional vector group (1/4)
MF2 = 0b111, // Fractional vector group (1/2)
};
/**
* Describes whether or not vector masks are agnostic.
*
* From the RVV spec:
*
* When a set is marked undisturbed, the corresponding set of
* destination elements in a vector register group retain the
* value they previously held.
*
* When a set is marked agnostic, the corresponding set of destination
* elements in any vector destination operand can either retain the value
* they previously held, or are overwritten with 1s.
*
* Within a single vector instruction, each destination element can be either
* left undisturbed or overwritten with 1s, in any combination, and the pattern
* of undisturbed or overwritten with 1s is not required to be deterministic when
* the instruction is executed with the same inputs. In addition, except for
* mask load instructions, any element in the tail of a mask result can also be
* written with the value the mask-producing operation would have calculated with vl=VLMAX
*/
enum class VMA : uint32_t {
No, // Undisturbed
Yes, // Agnostic
};
/**
* Describes whether or not vector tail elements are agnostic.
*
* From the RVV spec:
*
* When a set is marked undisturbed, the corresponding set of
* destination elements in a vector register group retain the
* value they previously held.
*
* When a set is marked agnostic, the corresponding set of destination
* elements in any vector destination operand can either retain the value
* they previously held, or are overwritten with 1s.
*
* Within a single vector instruction, each destination element can be either
* left undisturbed or overwritten with 1s, in any combination, and the pattern
* of undisturbed or overwritten with 1s is not required to be deterministic when
* the instruction is executed with the same inputs. In addition, except for
* mask load instructions, any element in the tail of a mask result can also be
* written with the value the mask-producing operation would have calculated with vl=VLMAX
*/
enum class VTA : uint32_t {
No, // Undisturbed
Yes, // Agnostic
};
} // namespace biscuit