公开(公告)号：US20130290683A1

公开(公告)日：2013-10-31

申请号：US13655622

申请日：2012-10-19

Applicant: QUALCOMM INCORPORATED

Inventor： Melinda J. Brown ,  Michael William Morrow ,  James Norris Dieffenderfer ,  Brian Michael Stempel ,  Michael Scott McIlvaine

IPC: G06F9/30

CPC classification number: G06F9/3017 ,  G06F9/30018 ,  G06F9/3838

Abstract: Eliminating redundant masking operations in instruction processing circuits and related processor systems, methods, and computer-readable media are disclosed. In one embodiment, a first instruction in an instruction stream indicating an operation writing a value to a first register is detected by an instruction processing circuit, the value having a value size less than a size of the first register. The circuit also detects a second instruction in the instruction stream indicating a masking operation on the first register. The masking operation is eliminated upon a determination that the masking operation indicates a read operation and a write operation on the first register and has an identity mask size equal to or greater than the value size. in this manner, the elimination of the masking operation avoids potential read-after-write hazards and improves performance of a CPU by removing redundant operations from an execution pipeline.

Abstract translation: 公开了在指令处理电路和相关处理器系统，方法和计算机可读介质中消除冗余掩蔽操作。 在一个实施例中，由指令处理电路检测指示将值写入第一寄存器的操作的指令流中的第一指令，该值具有小于第一寄存器的大小的值。 电路还检测指示流中指示在第一寄存器上的屏蔽操作的第二指令。 在确定掩蔽操作指示对第一寄存器的读取操作和写入操作并且具有等于或大于值大小的身份掩码大小的情况下，屏蔽操作被消除。 以这种方式，消除掩蔽操作避免了潜在的写后危害，并且通过从执行流水线中移除冗余操作来提高CPU的性能。

公开(公告)号：US10108419B2

公开(公告)日：2018-10-23

申请号：US14498938

申请日：2014-09-26

Applicant: QUALCOMM Incorporated

Inventor： Brian Michael Stempel ,  James Norris Dieffenderfer ,  Michael Scott McIlvaine ,  Melinda Joyce Brown

IPC: G06F9/40 ,  G06F9/42 ,  G06F9/44 ,  G06F9/30 ,  G06F9/38

Abstract: Systems and methods for dependency-prediction include executing instructions in an instruction pipeline of a processor and detecting a conditionality-imposing control instruction, such as an If-Then (IT) instruction, which imposes dependent behavior on a conditionality block size of one or more dependent instructions. Prior to executing a first instruction, a dependency-prediction is made to determine if the first instruction is a dependent instruction of the conditionality-imposing control instruction, based on the conditionality block size and one or more parameters of the instruction pipeline. The first instruction is executed based on the dependency-prediction. When the first instruction is dependency-mispredicted, an associated dependency-misprediction penalty is mitigated. If the first instruction is a branch instruction, the mitigation involves training a branch prediction tracking mechanism to correctly dependency-predict future occurrences of the first instruction.

公开(公告)号：US20140281394A1

公开(公告)日：2014-09-18

申请号：US13833844

申请日：2013-03-15

Applicant: QUALCOMM INCORPORATED

Inventor： Rodney Wayne Smith ,  Jeffery M. Schottmiller ,  Michael Scott McIlvaine ,  Brian Michael Stempel ,  Melinda J. Brown ,  Daren Eugene Streett

IPC: G06F9/30

CPC classification number: G06F9/30058 ,  G06F9/30054 ,  G06F9/3806

Abstract: An apparatus and method for executing call branch and return branch instructions in a processor by utilizing a link register stack. The processor includes a branch counter that is initialized to zero, and is set to zero each time the processor decodes a link register manipulating instruction other than a call branch instruction. The branch counter is incremented by one each time a call branch instruction is decoded and an address is pushed onto the link register stack. In response to decoding a return branch instruction and provided the branch counter is not zero, a target address for the decoded return branch instruction is popped off the link register stack, the branch counter is decremented, and there is no need to check the target address for correctness.

Abstract translation: 一种用于通过利用链路寄存器堆栈在处理器中执行呼叫分支和返回分支指令的装置和方法。 处理器包括初始化为零的分支计数器，并且每当处理器解码除了呼叫分支指令之外的链接寄存器操作指令时，该分支计数器被设置为零。 每当一个呼叫转移指令被解码并且一个地址被推到链路寄存器堆栈上时，分支计数器递增1。 响应于解码返回分支指令并且提供的分支计数器不为零，解码的返回分支指令的目标地址从链接寄存器堆栈中弹出，分支计数器递减，并且不需要检查目标地址 为正确。

公开(公告)号：US20190294443A1

公开(公告)日：2019-09-26

申请号：US15926429

申请日：2018-03-20

Applicant: QUALCOMM Incorporated

Inventor： Sandeep Suresh Navada ,  Michael Scott McIlvaine ,  Rodney Wayne Smith ,  Robert Douglas Clancy ,  Yusuf Cagatay Tekmen ,  Niket Choudhary ,  Daren Eugene Streett ,  Richard Doing ,  Ankita Upreti

IPC: G06F9/38

Abstract: Providing early pipeline optimization of conditional instructions in processor-based systems is disclosed. In one aspect, an instruction pipeline of a processor-based system detects a mispredicted branch (i.e., following a misprediction of a condition associated with a speculatively executed conditional branch instruction), and records a current state of one or more condition flags as a condition flags snapshot. After a pipeline flush is initiated and a corrected fetch path is restarted, an instruction decode stage of the instruction pipeline uses the condition flags snapshot to apply optimizations to conditional instructions detected within the corrected fetch path. According to some aspects, the condition flags snapshot is subsequently invalidated upon encountering a condition-flag-writing instruction within the corrected fetch path. In this manner, the condition flags snapshot enables non-speculative (with respect to the corrected fetch path) resolution of conditional instructions earlier within the instruction pipeline, thus conserving system resources and improving processor performance.

公开(公告)号：US09514061B1

公开(公告)日：2016-12-06

申请号：US14716947

申请日：2015-05-20

Applicant: QUALCOMM Incorporated

Inventor： Henry Arthur Pellerin, III ,  Thomas Philip Speier ,  Thomas Andrew Sartorius ,  Michael William Morrow ,  James Norris Dieffenderfer ,  Kenneth Alan Dockser ,  Michael Scott McIlvaine

IPC: G06F12/00 ,  G06F12/12 ,  G06F12/08

CPC classification number: G06F12/128 ,  G06F12/0855 ,  G06F12/0864 ,  G06F12/0875 ,  G06F12/0895 ,  G06F2212/1016 ,  G06F2212/401 ,  G06F2212/6032 ,  G06F2212/621

Abstract: A memory structure compresses a portion of a memory tag using an indexed tag compression structure. A set of higher order bits of the memory tag may be stored in the indexed tag compression structure, where the set of higher order bits are identified by an index value. A tag array stores a set of lower order bits of the memory tag and the index value identifying the entry in the tag compression structure storing the set of higher order bits of the memory tag. The memory tag may comprise at least a portion of a memory address of a data element stored in a data array.

Abstract translation: 存储器结构使用索引标签压缩结构压缩存储器标签的一部分。 存储器标签的一组较高位可以存储在索引标签压缩结构中，其中较高位的集合由索引值标识。 标签阵列存储存储器标签的一组较低位，以及标识在存储标签的较高位的集合的标签压缩结构中的条目的索引值。 存储器标签可以包括存储在数据阵列中的数据元素的存储器地址的至少一部分。

公开(公告)号：US09411590B2

公开(公告)日：2016-08-09

申请号：US13833844

申请日：2013-03-15

Applicant: QUALCOMM Incorporated

Inventor： Rodney Wayne Smith ,  Jeffery M. Schottmiller ,  Michael Scott McIlvaine ,  Brian Michael Stempel ,  Melinda J. Brown ,  Daren Eugene Streett

IPC: G06F9/30 ,  G06F9/38

CPC classification number: G06F9/30058 ,  G06F9/30054 ,  G06F9/3806

Abstract: An apparatus and method for executing call branch and return branch instructions in a processor by utilizing a link register stack. The processor includes a branch counter that is initialized to zero, and is set to zero each time the processor decodes a link register manipulating instruction other than a call branch instruction. The branch counter is incremented by one each time a call branch instruction is decoded and an address is pushed onto the link register stack. In response to decoding a return branch instruction and provided the branch counter is not zero, a target address for the decoded return branch instruction is popped off the link register stack, the branch counter is decremented, and there is no need to check the target address for correctness.

Abstract translation: 一种用于通过利用链路寄存器堆栈在处理器中执行呼叫分支和返回分支指令的装置和方法。 处理器包括初始化为零的分支计数器，并且每当处理器解码除了呼叫转移指令之外的链接寄存器操作指令时，该分支计数器被设置为零。 每当一个呼叫转移指令被解码并且一个地址被推到链路寄存器堆栈上时，分支计数器递增1。 响应于解码返回分支指令并且提供的分支计数器不为零，解码的返回分支指令的目标地址从链接寄存器堆栈中弹出，分支计数器递减，并且不需要检查目标地址 为正确。

公开(公告)号：US09317293B2

公开(公告)日：2016-04-19

申请号：US13792335

申请日：2013-03-11

Applicant: QUALCOMM Incorporated

Inventor： James Norris Dieffenderfer ,  Michael William Morrow ,  Michael Scott McIlvaine ,  Daren Eugene Streett ,  Vimal K. Reddy ,  Brian Michael Stempel

IPC: G06F9/38 ,  G06F9/30

CPC classification number: G06F9/3808 ,  G06F9/30054

Abstract: Establishing a branch target instruction cache (BTIC) entry for subroutine returns to reduce pipeline bubbles, and related systems, methods, and computer-readable media are disclosed. In one embodiment, a method of establishing a BTIC entry includes detecting a subroutine call in an execution pipeline. In response, at least one instruction fetched sequential to the subroutine call is written as a branch target instruction in a BTIC entry for a subroutine return. A next instruction fetch address is calculated, and is written into a next instruction fetch address field in the BTIC entry. In this manner, the BTIC may provide correct branch target instruction and next instruction fetch address data for the subroutine return, even if the subroutine return is encountered for the first time or the subroutine is called from different calling locations.

Abstract translation: 建立用于子程序的分支目标指令缓存（BTIC）条目返回以减少管道气泡，以及相关系统，方法和计算机可读介质。 在一个实施例中，建立BTIC条目的方法包括检测执行流水线中的子程序调用。 作为响应，在子程序返回的BTIC条目中写入与子程序调用顺序取得的至少一个指令作为分支目标指令。 计算下一个指令提取地址，并将其写入BTIC条目中的下一个指令获取地址字段。 以这种方式，即使第一次遇到子程序返回或从不同的呼叫位置调用子程序，BTIC可以为子程序返回提供正确的分支目标指令和下一个指令获取地址数据。

公开(公告)号：US09195466B2

公开(公告)日：2015-11-24

申请号：US13676146

申请日：2012-11-14

Applicant: QUALCOMM Incorporated

Inventor： Melinda J. Brown ,  James Norris Dieffenderfer ,  Michael Scott McIlvaine ,  Brian Michael Stempel ,  Rodney Wayne Smith ,  Jeffery M. Schottmiller ,  Andrew S. Irwin ,  Michael William Morrow

IPC: G06F7/38 ,  G06F9/00 ,  G06F9/38 ,  G06F9/30

CPC classification number: G06F9/3867 ,  G06F9/30043 ,  G06F9/30072 ,  G06F9/3017

Abstract: Fusing conditional write instructions having opposite conditions in instruction processing circuits and related processor systems, methods, and computer-readable media are disclosed. In one embodiment, a first conditional write instruction writing a first value to a target register based on evaluating a first condition is detected by an instruction processing circuit. The circuit also detects a second conditional write instruction writing a second value to the target register based on evaluating a second condition that is a logical opposite of the first condition. Either the first condition or the second condition is selected as a fused instruction condition, and corresponding values are selected as if-true and if-false values. A fused instruction is generated for selectively writing the if-true value to the target register if the fused instruction condition evaluates to true, and selectively writing the if-false value to the target register if the fused instruction condition evaluates to false.

Abstract translation: 公开了在指令处理电路和相关处理器系统，方法和计算机可读介质中具有相反条件的条件写指令。 在一个实施例中，由指令处理电路检测基于评估第一条件将第一值写入目标寄存器的第一条件写入指令。 该电路还基于评估与第一条件逻辑相反的第二条件，检测向目标寄存器写入第二值的第二条件写入指令。 选择第一个条件或第二个条件作为融合指令条件，并将相应的值选为if-true和if-false值。 如果融合指令条件评估为真，则生成融合指令，以便如果融合指令条件评估为真，则将if-true值有选择地写入目标寄存器，如果融合指令条件评估为false，则选择性地将if-false值写入目标寄存器。

公开(公告)号：US10474462B2

公开(公告)日：2019-11-12

申请号：US15057116

申请日：2016-02-29

Applicant: QUALCOMM Incorporated

Inventor： Shivam Priyadarshi ,  Rami Mohammad Al Sheikh ,  Raguram Damodaran ,  Michael Scott McIlvaine ,  Jeffrey Todd Bridges

IPC: G06F9/30 ,  G06F9/38

Abstract: Systems and methods for operating a processor include determining confidence levels, such as high, low, and medium confidence levels, associated with in-flight branch instructions in an instruction pipeline of the processor, based on counters used for predicting directions of the in-flight branch instructions. Numbers of in-flight branch instructions associated with each of confidence levels are determined. A weighted sum of the numbers weighted with weights corresponding to the confidence levels is calculated and the weighted sum is compared with a threshold. A throttling signal may be asserted to indicate that instructions are to be throttled in a pipeline stage of the instruction pipeline based on the comparison.

公开(公告)号：US10318436B2

公开(公告)日：2019-06-11

申请号：US15658819

申请日：2017-07-25

Applicant: QUALCOMM Incorporated

Inventor： William McAvoy ,  Brian Stempel ,  Spencer Williams ,  Robert Douglas Clancy ,  Michael Scott McIlvaine ,  Thomas Philip Speier

IPC: G06F12/00 ,  G06F12/1045 ,  G06F12/0891 ,  G06F12/0895 ,  G06F13/00 ,  G06F13/28

Abstract: A translation lookaside buffer (TLB) index valid bit is set in a first line of a virtually indexed, virtually tagged (VIVT) cache. The first line of the VIVT cache is associated with a first TLB entry which stores a virtual address to physical address translation for the first cache line. The TLB index valid bit of the first line is cleared upon determining that the translation is no longer stored in the first TLB entry. An indication of a received invalidation instruction is stored. When a context synchronization instruction is received, the first line of the VIVT cache is cleared based on the TLB index valid bit being cleared and the stored indication of the invalidate instruction.