Forming instruction groups based on decode time instruction optimization

Patent metadata

Field	Value
Publication number	US-9361108-B2
Application number	US-201414550955-A
Country	US
Kind code	B2
Filing date	Nov 22, 2014
Priority date	Jun 28, 2013
Publication date	Jun 7, 2016
Grant date	Jun 7, 2016

Abstract

Instructions are grouped into instruction groups based on optimizations that may be performed. An instruction is obtained, and a determination is made as to whether the instruction is to be included in a current instruction group or another instruction group. This determination is made based on whether the instruction is a candidate for optimization, such as decode time instruction optimization. If it is determined that the instruction is to be included in another group, then the other group is formed to include the instruction.

First claim

The invention claimed is:

1. A method of facilitating processing in a processing environment, said method comprising:
obtaining an instruction to be executed in the processing environment;
determining whether the instruction is to be included in a current group of instructions or a new group of instructions, wherein the determining is based on whether the instruction is a candidate for optimization with another instruction according to an optimization criterion, and wherein the determining further comprises:
checking whether an instruction sequence to be optimized that includes at least the instruction and the other instruction fits in the current group of instructions, which the checking includes checking a marker associated with the instruction, the marker indicating a length of the instruction sequence; and
forming the new group of instructions based on determining the instruction is a candidate for optimization and the instruction sequence does not fit in the current group of instructions, wherein the new group of instructions includes the instruction and the other instruction; and
based on forming the new group of instructions, executing at least one instruction associated with the new group of instructions.

2. The method of claim 1 , wherein the determining comprises determining whether the instruction represents a beginning of a potential optimization sequence that includes the instruction and the other instruction, and wherein the forming forms the new group of instructions based on the instruction representing the beginning of a potential optimization sequence.

3. The method of claim 2 , wherein the determining whether the instruction represents the beginning of a potential optimization sequence comprises checking a selected marker associated with the instruction, the selected marker indicating whether the instruction starts a potential optimization sequence.

4. The method of claim 3 , further comprising marking the instruction with the selected marker, the selected marker indicating one of: the instruction is considered as representing the beginning of a potential optimization sequence, or the instruction is not considered as representing the beginning of a potential optimization sequence, and wherein the marking is performed at instruction fetch.

5. The method of claim 1 , further comprising:
determining a number of instructions in the instruction sequence; and
marking the instruction with a marker that indicates the number of instructions, the marking being performed at instruction fetch.

6. The method of claim 1 , wherein the optimization criterion is specified in one or more templates, and wherein at least one template of the one or more templates is to be used to determine whether the instruction is a candidate for optimization.

7. The method of claim 1 , wherein the optimization criterion optimizes the instruction and the other instruction by creating at least one internal operation that represents at least a portion of the instruction and at least a portion of the other instruction.

8. The method of claim 1 , wherein the optimization is performed at decode time.

Assignees

• IBM

Inventors

• Gschwind Michael K

Classifications

• G06F8/443

  Optimisation · CPC title

• G06F9/3016

  Decoding the operand specifier, e.g. specifier format · CPC title

• G06F9/30145 Primary

  Instruction analysis, e.g. decoding, instruction word fields · CPC title

• G06F9/3853

  of compound instructions · CPC title

• G06F9/3822

  Parallel decoding, e.g. parallel decode units · CPC title