Oracle America, Inc.

Sun Microsystems, Inc.

Marvell Asia Pte., Ltd.

Oracle International Corporation

Fu-Hwa Wang

Sheldon M Lobo

Maksim V Panchenko

Chandrashekhar R Garud

Ulf Hanebutte

Senad Durakovic

Kurt J Goebel

Raj Prakash

Chien-Chun Chou

Dmitri Shtilman

Harri Hakkarainen

Mohana Tandyala

Veena Karthikeyan

A method includes receiving a high-level function in a first high-level code; compiling the high-level function into a first set of low-level instructions to be executed on a hardware or a simulator; transmitting the first set of low-level instructions to the hardware or the simulator; receiving a plurality of statistical data generated by the hardware or the simulator in response to execution of the first set of low-level instructions, wherein the plurality of statistical data is performance related; determining whether to make changes to the compilation associated with the high-level function in the first high-level code based on the plurality of statistical data; recompiling the high-level function into a second set of low-level instructions to be executed on the hardware or the simulator based on the changes to the compilation; and transmitting the second set of low-level instructions to the hardware or the simulator.

Method and system for code optimization based on statistical data

A system includes a compiler including a plurality of compiler blocks. The compiler blocks of the plurality of compiler blocks are compossible. The compiler is configured to identify one or more resources in a hardware to execute a set of low-level instructions that is generated from a high-level function in a high-level code. The compiler is further configured to determine one or more processing operations to be performed that is associated with the high-level function in the high-level code. The determining of the one or more processing operations occurs based on architecture of the hardware. The compiler is configured to compile the high-level function in the high-level code of the application into the set of low-level instructions to be executed on the hardware.

Multistage compiler architecture

Duplicative code found in modules of high level computer code can be eliminated at link-time. A compiler forms a plurality of object files from a software program in which each object file includes one or more functions associated with the software program. An analyzer examines each function to ascertain whether any of the plurality of object files include functional duplicates. In addition, call and caller routing references are determined for each of the object files and functions contained therein. Responsive to determining that a functional equivalence exists, the routing of duplicative functions is altered to reference a golden copy of the same function. Once the call and caller information has been re-routed, the duplicative function(s) is(are) deleted.

Link-time redundant code elimination using functional equivalence

A system performs operations comprising creating a call graph for a program translated from source code, identifying redundant exception handling code in the program utilizing the call graph, and removing the redundant exception handling code. The operation of identifying redundant exception handling code may comprise identifying at least one function or callsite by determining that a first function in the at least one function's or callsite's callee chain throws an exception and that the exception is handled by a second function in the function's or callsite's callee chain or by determining that an exception is not thrown in the at least one function's or callsite's callee chain. The operation of removing the redundant exception handling code may comprise removing redundant exception handling code included in at least one function or callsite and/or removing at least one entry for the at least one function or callsite from an exception lookup table.

Redundant exception handling code removal

A system and method for performing efficient program instrumentation for memory profiling. A computing system comprises a memory profiler comprising a static binary instrumentation (SBI) tool and a dynamic binary analysis (DBA) tool. The profiler is configured to selectively instrument memory access operations of a software application. Instrumentation may be bypassed completely for an instruction if the instruction satisfies some predetermined conditions. Some sample conditions include the instruction accesses an address within a predetermined read-only area, the instruction accesses an address within a user-specified address range, and/or the instruction is a load instruction accessing a memory location determined from a data flow graph to store an initialized value. An instrumented memory access instruction may have memory checking analysis performed only upon an initial execution of the instruction in response to determining during initial execution that a read data value of the instruction is initialized. Both unnecessary instrumentation and memory checking analysis may be reduced.

Method and system for efficient tracing and profiling of memory accesses during program execution

A method and system for providing a binary instrumentation tool to detect memory problems in a runtime application executing on a computer system includes identifying one or more functions or statements in the runtime application. A plurality of compiler annotations defining essential functional characteristic data of each of the plurality of functions is generated by a compiler when compiling the user program from source code to an executable binary code. A program error detector is configured to provide a checker code based on guidelines provided by of the plurality of compiler annotations associated with the function. The program error detector generates a modified function code for the identified function by inserting the checker code into a function code for the corresponding function. A modified executable binary code for the runtime application is then generated by replacing the function code for the function with the corresponding modified function code. When the modified executable binary code is run, the checker code associated with the function invokes a checker. The invoked checker provides performance data analysis that allows identification of program errors including memory errors in the runtime application.

Method and system for detecting memory problems in user programs

It has been discovered that a control transfer table can be structured to reduce the overhead resulting from its use (e.g., misses from accessing the control transfer table). Entries of a control transfer table (e.g., a jump table or a procedure linkage table) can be organized in accordance with their respective use frequencies, as well as other parameters. For example, entries can be organized in a manner that would group the most frequently used entries, thus facilitating their contemporaneous availability in a memory (e.g., cache). The use frequencies may be determined from profile information for a code that references the control transfer table.

Control transfer table structuring

Automatically executing commands to process code (e.g., compile commands, interpret commands, etc.) and recording code characteristic metric values (e.g., file size, execution time, etc.) allows automatic code tuning. The automatic turning system may execute predefined commands on codes, automatically intelligently build commands, both execute predefined commands and intelligently build upon those predefined commands, etc. With the automatic intelligent building of commands to build more effective commands, an automatic tuning system can efficiently and judiciously search through available code development tool options to find the more effective combinations of options to generate executable codes.

Automatic code tuning

Techniques for reliable binary instrumentation based on annotation information are described. A binary file that comprises a code section representing the executable code of a computer program is accessed. The binary file also comprises annotation information that indicates the boundaries of one or more portions of the computer program. Accurate data flow information and control flow information may be generated based on the annotation information included in the binary file. The binary file is instrumented by inserting a set of instrumentation code at one or more points in the code section of the computer program. The one or more points are determined based on the data flow information and the control flow information.

Binary profile instrumentation framework

A code, which may be a post-link binary or a pre-link object file, can be transformed to optimize code fragments that implement loading a constant from memory. A constant loading code fragment includes address computing operations that compute (or copy) an address representation of a constant for consumption by a memory access operation, and the memory access operation that loads the constant. Information from control flow analysis, data flow analysis, and binary structure/configuration analysis are examined to identify code fragments of a code that implement constant loading. A tool transforms the code to convert the identified code fragments. To optimize, the tool may convert operations, eliminate operations, convert indirect calls to direct calls, inline functions called indirectly, eliminate unused constant data, modify relocations, etc. This optimization can also be applied recursively. The same tool or another tool can subsequently analyze the transformed code one more times to identify additional opportunities for optimizations revealed by the transformation or to apply the transformation for a different profile of the application.

Code transformation to optimize fragments that implement constant loading

An application compiled to a binary executable according to a first set of binary interface rules has selected caller/callee pairs that present parameter passing improvement possibilities modified from compliance with the first set of binary interface rules to compliance with a second set of binary interface rules to improve the efficiency of parameter passing, such as by reducing the number of instructions used to pass the parameters. A binary executable search engine searches the binary executable to locate functions having parameter passing improvement possibilities. Identified caller/callee function pairs are updated with a function modifier to pass the parameters more efficiently. Selected of the identified callee functions are cloned so that a cloned function is modified instead of the original function, thus leaving the original function to pass parameters with functions beyond the view of the binary executable search engine.

System and method for binary translation to improve parameter passing

Techniques for reordering the data section of a computer program are provided for improving the run-time performance of the program. A computer program that comprises a data section and a code section is compiled. After the computer program has been compiled, the data section of the computer program is reordered based at least on annotation information that is included in a plurality of object files that represent the object code of the program. A specific binary file that is a specific executable version of the computer program is generated. The specific binary file includes the data section of the computer program that has been reordered. The data section of the computer program may be reordered during the linking of the plurality of the object files. Alternatively, the data section may be reordered after the computer program has been linked into a first binary file by rewriting the first binary file into the specific binary file.

Data reordering for improved cache operation

A system and method for optimizing compiler performance including outlining cold code at link time, rather than compile time, such that trampolines are not required. Branch instructions connecting a hot block to a cold block can be converted from a short branch distance limit to a longer branch distance limit, further optimizing code performance. Editors, implementing a plurality of windows that can be maintained for each function, can display the maximum distance that code blocks can be safely outlined. Other implementations allow the optimal placement of code that is significantly greater in size than the maximum possible branch distance.

Code outlining without trampolines

Performance information can be utilized for comparison of resolving an external object reference through a linking module against accessing the external object directly ('relocation processing'). With the performance information, a determination of whether performing relocation processing on a runtime linked external object reference provides improved runtime performance sufficient to outweigh the runtime linking overhead incurred from the relocation processing is made. If the improvement in runtime performance is sufficient, then the runtime linked external object reference, or the code section that includes the reference, is marked to indicate that relocation processing should be applied.

Intelligent processing of external object references for dynamic linking

Techniques for preparing a binary file for future instrumentation are provided. First object code and second object code are linked into a binary file. The first object code is created by compiling the source code of a computer program. The second object code comprises a first set of instrumentation code that is not referenced by any instructions in the object code of the computer program. The second object code stores commonly used instrumentation routines that are referenced by a second set of instrumentation code, which second set is inserted in the binary file when the binary file is subsequently instrumented.

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Fu-Hwa Wang