摘要:
In one embodiment, a processor includes an instruction decoder to receive a first instruction having a prefix and an opcode and to generate, by an instruction decoder of the processor, a second instruction executable based on a condition determined based on the prefix, and an execution unit to conditionally execute the second instruction based on the condition determined based on the prefix.
摘要:
Receiving an instruction indicating a source operand and a destination operand. Storing a result in the destination operand in response to the instruction. The result operand may have: (1) first range of bits having a first end explicitly specified by the instruction in which each bit is identical in value to a bit of the source operand in a corresponding position; and (2) second range of bits that all have a same value regardless of values of bits of the source operand in corresponding positions. Execution of instruction may complete without moving the first range of the result relative to the bits of identical value in the corresponding positions of the source operand, regardless of the location of the first range of bits in the result. Execution units to execute such instructions, computer systems having processors to execute such instructions, and machine-readable medium storing such an instruction are also disclosed.
摘要:
Techniques for using and/or supporting multiplication with add and/or subtract instructions with an intermediate (after multiplication) round are described. In some examples, an instruction at least having one or more fields for an opcode and location information for three packed data source operands, wherein the opcode is to indicate execution circuitry is to perform, per packed data element position, a multiplication, a round, addition and/or subtraction, and a round, using the three packed data source operands and storage into a corresponding packed data element position of an identified destination location, wherein which packed data element positions are to be added and subtracted is defined by the opcode is supported.
摘要:
In one embodiment, a processor includes an instruction decoder to receive a first instruction having a prefix and an opcode and to generate, by an instruction decoder of the processor, a second instruction executable based on a condition determined based on the prefix, and an execution unit to conditionally execute the second instruction based on the condition determined based on the prefix.
摘要:
Methods and apparatus are disclosed for fusing instructions to provide OR-test and AND-test functionality on multiple test sources. Some embodiments include fetching instructions, said instructions including a first instruction specifying a first operand destination, a second instruction specifying a second operand source, and a third instruction specifying a branch condition. A portion of the plurality of instructions are fused into a single micro-operation, the portion including both the first and second instructions if said first operand destination and said second operand source are the same, and said branch condition is dependent upon the second instruction. Some embodiments generate a novel test instruction dynamically by fusing one logical instruction with a prior-art test instruction. Other embodiments generate the novel test instruction through a just-in-time compiler. Some embodiments also fuse the novel test instruction with a subsequent conditional branch instruction, and perform a branch according to how the condition flag is set.
摘要:
A method of one aspect may include receiving a rotate instruction. The rotate instruction may indicate a source operand and a rotate amount. A result may be stored in a destination operand indicated by the rotate instruction. The result may have the source operand rotated by the rotate amount. Execution of the rotate instruction may complete without reading a carry flag.
摘要:
A method in one aspect may include receiving a multiply instruction. The multiply instruction may indicate a first source operand and a second source operand. A product of the first and second source operands may be stored in one or more destination operands indicated by the multiply instruction. Execution of the multiply instruction may complete without writing a carry flag. Other methods are also disclosed, as are apparatus, systems, and instructions on machine-readable medium.
摘要:
Fusible instructions and logic provide OR-test and AND-test functionality on multiple test sources. Some embodiments include a processor decode stage to decode a test instruction for execution, the instruction specifying first, second and third source data operands, and an operation type. Execution units, responsive to the decoded test instruction, perform one logical operation, according to the specified operation type, between data from the first and second source data operands, and perform a second logical operation between the data from the third source data operand and the result of the first logical operation to set a condition flag. Some embodiments generate the test instruction dynamically by fusing one logical instruction with a prior-art test instruction. Other embodiments generate the test instruction through a just-in-time compiler. Some embodiments also fuse the test instruction with a subsequent conditional branch instruction, and perform a branch according to how the condition flag is set.
摘要:
Receiving an instruction indicating a source operand and a destination operand. Storing a result in the destination operand in response to the instruction. The result operand may have: (1) first range of bits having a first end explicitly specified by the instruction in which each bit is identical in value to a bit of the source operand in a corresponding position; and (2) second range of bits that all have a same value regardless of values of bits of the source operand in corresponding positions. Execution of instruction may complete without moving the first range of the result relative to the bits of identical value in the corresponding positions of the source operand, regardless of the location of the first range of bits in the result. Execution units to execute such instructions, computer systems having processors to execute such instructions, and machine-readable medium storing such an instruction are also disclosed.
摘要:
A method of one aspect may include receiving a rotate instruction. The rotate instruction may indicate a source operand and a rotate amount. A result may be stored in a destination operand indicated by the rotate instruction. The result may have the source operand rotated by the rotate amount. Execution of the rotate instruction may complete without reading a carry flag.