SPEC CPU®2026 Flag Description
Supermicro SuperServer SYS-112HA-TN (X14SBH-AP , Intel Xeon 6990E+)

Base Optimization Flags

C benchmarks

• • -m64
  • 
  • intel_icc,intel_icpc,intel_ifort,intel_icx,intel_icpx,intel_ifx
  • CC, LD

  • Compiles for a 64-bit (LP64) data model.

• • -std=c18
  • 
  • intel_icx,intel_icpx
  • CC, LD

  • Sets the language standard to the specified version, for example c18, c++17, f2008.

• • -Wl,-z,muldefs
  • 
  • EXTRA_LDFLAGS

  • Enable SmartHeap and/or other library usage by forcing the linker to ignore multiple definitions if present

• • -Wl,-plugin-opt=-inline-threshold=1500
  • 
  • EXTRA_LDFLAGS

  • Controls the compiler's inlining threshold by adjusting the value passed as an argument

• • -xclearwaterforest
  • 
  • COPTIMIZE

  • May generate instructions for processors that support the specified Intel processor or microarchitecture code name. Optimizes for the specified Intel processor or microarchitecture code name.

• • -O3
  • 
  • COPTIMIZE

  • Enable O2 optimizations plus more aggressive optimizations, such as prefetching, scalar replacement, and loop and memory access transformations. Enable optimizations for maximum speed, such as:

    • Loop unrolling, including instruction scheduling
    • Code replication to eliminate branches
    • Padding the size of certain power-of-two arrays to allow more efficient cache use.
    
    

    On IA-32 and Intel EM64T processors, when O3 is used with options -ax or -x (Linux) or with options /Qax or /Qx (Windows), the compiler performs more aggressive data dependency analysis than for O2, which may result in longer compilation times. The O3 optimizations may not cause higher performance unless loop and memory access transformations take place. The optimizations may slow down code in some cases compared to O2 optimizations. The O3 option is recommended for applications that have loops that heavily use floating-point calculations and process large data sets.

  • Includes:
    • -O2
      • -O1
        • -funroll-loops
        • -fno-builtin
        • -mno-ieee-fp
        • -fomit-framepointer
        • -ffunction-sections
        • -ftz
• • -ffp-model=fast
  • 
  • COPTIMIZE

  • Tells the compiler to use more aggressive optimizations when implementing floating-point calculations. These optimizations increase speed, but they may affect the accuracy or reproducibility of floating-point computations.

    Specifying fast is the same as specifying fast=1. Setting fast=1 (the default) recognizes and supports NaN and infinite values.

• • -flto
  • 
  • COPTIMIZE

  • Performs link time optimizations, which is also known as Interprocedural Optimizations.

• • -mfpmath=sse
  • 
  • COPTIMIZE

  • Generate floating-point arithmetic for the selected unit. When set to "sse" use scalar floating-point instructions present in the SSE instruction set.

• • -funroll-loops
  • 
  • COPTIMIZE

  • Tells the compiler the maximum number of times to unroll loops. For example -funroll-loops0 would disable unrolling of loops.

• • -qopt-mem-layout-trans=4
  • 
  • COPTIMIZE

  • Controls the level of memory layout transformations performed by the compiler. This option can improve cache reuse and cache locality.

    • 0: Disables memory layout transformations. This is the same as specifying -qno-opt-mem-layout-trans
    • 1: Enable basic memory layout transformations like structure splitting, structure peeling, field inlining, field reordering, array field transpose, increase field alignment etc.
    • 2: Enable more memory layout transformations like advanced structure splitting. This is the same as specifying -qopt-mem-layout-trans
    • 3: Enable more memory layout transformations like copy-in/copy-out of structures for a region of code. You should only use this setting if your system has more than 4GB of physical memory per core.
    • 4: Compiler is more aggressive in using memory layout transformations. You should only use this setting if your system has more than 4GB of physical memory per core.
• • -fno-strict-aliasing
  • 
  • EXTRA_CFLAGS

  • Disable use of strict aliasing rules in optimizations.

• • -fiopenmp
  • 
  • Yes
  • EXTRA_COPTIMIZE

  • Enable the compiler to generate multi-threaded code based on the OpenMP* directives.

• • -DSPEC_OPENMP
  • 
  • EXTRA_COPTIMIZE

  • Definition of this macro indicates that compilation for parallel operation is enabled, and that any OpenMP directives or pragmas will be visible to the compiler. The behavior of this macro is overridden if -DSPEC_SUPPRESS_OPENMP also appears in the list of compilation flags.

• • -L/usr/local/jemalloc-5.3.0/lib
  • 
  • EXTRA_LIBS

  • Build time link path for libraries supplied with the compiler (for example, the qkmalloc library).

• • -ljemalloc
  • 
  • EXTRA_LIBS

  • Linker toggle to specify jemalloc linker library. See jemalloc.net for more information.

C++ benchmarks

• • -m64
  • 
  • intel_icc,intel_icpc,intel_ifort,intel_icx,intel_icpx,intel_ifx
  • CXX, LD

  • Compiles for a 64-bit (LP64) data model.

• • -std=c++17
  • 
  • intel_icx,intel_icpx
  • CXX, LD

  • Sets the language standard to the specified version, for example c18, c++17, f2008.

• • -Wl,-z,muldefs
  • 
  • EXTRA_LDFLAGS

  • Enable SmartHeap and/or other library usage by forcing the linker to ignore multiple definitions if present

• • -Wl,-plugin-opt=-inline-threshold=1500
  • 
  • EXTRA_LDFLAGS

  • Controls the compiler's inlining threshold by adjusting the value passed as an argument

• • -xclearwaterforest
  • 
  • CXXOPTIMIZE

  • May generate instructions for processors that support the specified Intel processor or microarchitecture code name. Optimizes for the specified Intel processor or microarchitecture code name.

• • -O3
  • 
  • CXXOPTIMIZE

  • Enable O2 optimizations plus more aggressive optimizations, such as prefetching, scalar replacement, and loop and memory access transformations. Enable optimizations for maximum speed, such as:

    • Loop unrolling, including instruction scheduling
    • Code replication to eliminate branches
    • Padding the size of certain power-of-two arrays to allow more efficient cache use.
    
    

    On IA-32 and Intel EM64T processors, when O3 is used with options -ax or -x (Linux) or with options /Qax or /Qx (Windows), the compiler performs more aggressive data dependency analysis than for O2, which may result in longer compilation times. The O3 optimizations may not cause higher performance unless loop and memory access transformations take place. The optimizations may slow down code in some cases compared to O2 optimizations. The O3 option is recommended for applications that have loops that heavily use floating-point calculations and process large data sets.

  • Includes:
    • -O2
      • -O1
        • -funroll-loops
        • -fno-builtin
        • -mno-ieee-fp
        • -fomit-framepointer
        • -ffunction-sections
        • -ftz
• • -ffp-model=fast
  • 
  • CXXOPTIMIZE

  • Tells the compiler to use more aggressive optimizations when implementing floating-point calculations. These optimizations increase speed, but they may affect the accuracy or reproducibility of floating-point computations.

    Specifying fast is the same as specifying fast=1. Setting fast=1 (the default) recognizes and supports NaN and infinite values.

• • -flto
  • 
  • CXXOPTIMIZE

  • Performs link time optimizations, which is also known as Interprocedural Optimizations.

• • -mfpmath=sse
  • 
  • CXXOPTIMIZE

  • Generate floating-point arithmetic for the selected unit. When set to "sse" use scalar floating-point instructions present in the SSE instruction set.

• • -funroll-loops
  • 
  • CXXOPTIMIZE

  • Tells the compiler the maximum number of times to unroll loops. For example -funroll-loops0 would disable unrolling of loops.

• • -qopt-mem-layout-trans=4
  • 
  • CXXOPTIMIZE

  • Controls the level of memory layout transformations performed by the compiler. This option can improve cache reuse and cache locality.

    • 0: Disables memory layout transformations. This is the same as specifying -qno-opt-mem-layout-trans
    • 1: Enable basic memory layout transformations like structure splitting, structure peeling, field inlining, field reordering, array field transpose, increase field alignment etc.
    • 2: Enable more memory layout transformations like advanced structure splitting. This is the same as specifying -qopt-mem-layout-trans
    • 3: Enable more memory layout transformations like copy-in/copy-out of structures for a region of code. You should only use this setting if your system has more than 4GB of physical memory per core.
    • 4: Compiler is more aggressive in using memory layout transformations. You should only use this setting if your system has more than 4GB of physical memory per core.
• • -pthread
  • 
  • EXTRA_CXXOPTIMIZE

  • Enable support for Posix Threads. Note that C++ programs using std::thread may require this flag.

• • -fiopenmp
  • 
  • Yes
  • EXTRA_CXXOPTIMIZE

  • Enable the compiler to generate multi-threaded code based on the OpenMP* directives.

• • -DSPEC_OPENMP
  • 
  • EXTRA_CXXOPTIMIZE

  • Definition of this macro indicates that compilation for parallel operation is enabled, and that any OpenMP directives or pragmas will be visible to the compiler. The behavior of this macro is overridden if -DSPEC_SUPPRESS_OPENMP also appears in the list of compilation flags.

• • -L/usr/local/jemalloc-5.3.0/lib
  • 
  • EXTRA_LIBS

  • Build time link path for libraries supplied with the compiler (for example, the qkmalloc library).

• • -ljemalloc
  • 
  • EXTRA_LIBS

  • Linker toggle to specify jemalloc linker library. See jemalloc.net for more information.

Benchmarks using both C and C++

• • -m64
  • 
  • intel_icc,intel_icpc,intel_ifort,intel_icx,intel_icpx,intel_ifx
  • CC, CXX, LD

  • Compiles for a 64-bit (LP64) data model.

• • -std=c++17
  • 
  • intel_icx,intel_icpx
  • CXX, LD

  • Sets the language standard to the specified version, for example c18, c++17, f2008.

• • -std=c18
  • 
  • intel_icx,intel_icpx
  • CC

  • Sets the language standard to the specified version, for example c18, c++17, f2008.

• • -Wl,-z,muldefs
  • 
  • EXTRA_LDFLAGS

  • Enable SmartHeap and/or other library usage by forcing the linker to ignore multiple definitions if present

• • -Wl,-plugin-opt=-inline-threshold=1500
  • 
  • EXTRA_LDFLAGS

  • Controls the compiler's inlining threshold by adjusting the value passed as an argument

• • -xclearwaterforest
  • 
  • COPTIMIZE, CXXOPTIMIZE

  • May generate instructions for processors that support the specified Intel processor or microarchitecture code name. Optimizes for the specified Intel processor or microarchitecture code name.

• • -O3
  • 
  • COPTIMIZE, CXXOPTIMIZE

  • Enable O2 optimizations plus more aggressive optimizations, such as prefetching, scalar replacement, and loop and memory access transformations. Enable optimizations for maximum speed, such as:

    • Loop unrolling, including instruction scheduling
    • Code replication to eliminate branches
    • Padding the size of certain power-of-two arrays to allow more efficient cache use.
    
    

    On IA-32 and Intel EM64T processors, when O3 is used with options -ax or -x (Linux) or with options /Qax or /Qx (Windows), the compiler performs more aggressive data dependency analysis than for O2, which may result in longer compilation times. The O3 optimizations may not cause higher performance unless loop and memory access transformations take place. The optimizations may slow down code in some cases compared to O2 optimizations. The O3 option is recommended for applications that have loops that heavily use floating-point calculations and process large data sets.

  • Includes:
    • -O2
      • -O1
        • -funroll-loops
        • -fno-builtin
        • -mno-ieee-fp
        • -fomit-framepointer
        • -ffunction-sections
        • -ftz
• • -ffp-model=fast
  • 
  • COPTIMIZE, CXXOPTIMIZE

  • Tells the compiler to use more aggressive optimizations when implementing floating-point calculations. These optimizations increase speed, but they may affect the accuracy or reproducibility of floating-point computations.

    Specifying fast is the same as specifying fast=1. Setting fast=1 (the default) recognizes and supports NaN and infinite values.

• • -flto
  • 
  • COPTIMIZE, CXXOPTIMIZE

  • Performs link time optimizations, which is also known as Interprocedural Optimizations.

• • -mfpmath=sse
  • 
  • COPTIMIZE, CXXOPTIMIZE

  • Generate floating-point arithmetic for the selected unit. When set to "sse" use scalar floating-point instructions present in the SSE instruction set.

• • -funroll-loops
  • 
  • COPTIMIZE, CXXOPTIMIZE

  • Tells the compiler the maximum number of times to unroll loops. For example -funroll-loops0 would disable unrolling of loops.

• • -qopt-mem-layout-trans=4
  • 
  • COPTIMIZE, CXXOPTIMIZE

  • Controls the level of memory layout transformations performed by the compiler. This option can improve cache reuse and cache locality.

    • 0: Disables memory layout transformations. This is the same as specifying -qno-opt-mem-layout-trans
    • 1: Enable basic memory layout transformations like structure splitting, structure peeling, field inlining, field reordering, array field transpose, increase field alignment etc.
    • 2: Enable more memory layout transformations like advanced structure splitting. This is the same as specifying -qopt-mem-layout-trans
    • 3: Enable more memory layout transformations like copy-in/copy-out of structures for a region of code. You should only use this setting if your system has more than 4GB of physical memory per core.
    • 4: Compiler is more aggressive in using memory layout transformations. You should only use this setting if your system has more than 4GB of physical memory per core.
• • -fno-strict-aliasing
  • 
  • EXTRA_CFLAGS

  • Disable use of strict aliasing rules in optimizations.

• • -fiopenmp
  • 
  • Yes
  • EXTRA_COPTIMIZE, EXTRA_CXXOPTIMIZE

  • Enable the compiler to generate multi-threaded code based on the OpenMP* directives.

• • -DSPEC_OPENMP
  • 
  • EXTRA_COPTIMIZE, EXTRA_CXXOPTIMIZE

  • Definition of this macro indicates that compilation for parallel operation is enabled, and that any OpenMP directives or pragmas will be visible to the compiler. The behavior of this macro is overridden if -DSPEC_SUPPRESS_OPENMP also appears in the list of compilation flags.

• • -pthread
  • 
  • EXTRA_CXXOPTIMIZE

  • Enable support for Posix Threads. Note that C++ programs using std::thread may require this flag.

• • -L/usr/local/jemalloc-5.3.0/lib
  • 
  • EXTRA_LIBS

  • Build time link path for libraries supplied with the compiler (for example, the qkmalloc library).

• • -ljemalloc
  • 
  • EXTRA_LIBS

  • Linker toggle to specify jemalloc linker library. See jemalloc.net for more information.

Peak Optimization Flags

C benchmarks

854.graph500_s

• • basepeak = yes

C++ benchmarks

807.ntest_s

• • basepeak = yes

827.cppcheck_s

• • basepeak = yes

853.ns3_s

• • -m64
  • 
  • intel_icc,intel_icpc,intel_ifort,intel_icx,intel_icpx,intel_ifx
  • CXX, LD

  • Compiles for a 64-bit (LP64) data model.

• • -std=c++17
  • 
  • intel_icx,intel_icpx
  • CXX, LD

  • Sets the language standard to the specified version, for example c18, c++17, f2008.

• • -Wl,-z,muldefs
  • 
  • EXTRA_LDFLAGS

  • Enable SmartHeap and/or other library usage by forcing the linker to ignore multiple definitions if present

• • -Wl,-plugin-opt=-inline-threshold=1500
  • 
  • EXTRA_LDFLAGS

  • Controls the compiler's inlining threshold by adjusting the value passed as an argument

• • -fprofile-generate
  • 
  • PASS1_CXXFLAGS, PASS1_LDFLAGS

  • Instrument program for profiling for the first phase of two-phase profile guided optimization. This instrumentation gathers information about a program's execution paths and data values but does not gather information from hardware performance counters. The profile instrumentation also gathers data for optimizations which are unique to profile-feedback optimization.

• • -fprofile-use=default.profdata
  • 
  • PASS2_CXXFLAGS, PASS2_LDFLAGS

  • Instructs the compiler to produce a profile-optimized executable and merges available dynamic information.

• • -xCORE-AVX2
  • 
  • PASS1_CXXFLAGS, PASS1_LDFLAGS

  • Code is optimized for Intel(R) processors with support for AVX2 instructions. The resulting code may contain unconditional use of features that are not supported on other processors. This option also enables new optimizations in addition to Intel processor-specific optimizations including advanced data layout and code restructuring optimizations to improve memory accesses for Intel processors.

    Do not use this option if you are executing a program on a processor that is not an Intel processor. If you use this option on a non-compatible processor to compile the main program (in Fortran) or the function main() in C/C++, the program will display a fatal run-time error if they are executed on unsupported processors.

• • -ffp-model=fast
  • 
  • CXXOPTIMIZE, PASS1_LDFLAGS, PASS2_LDFLAGS

  • Tells the compiler to use more aggressive optimizations when implementing floating-point calculations. These optimizations increase speed, but they may affect the accuracy or reproducibility of floating-point computations.

    Specifying fast is the same as specifying fast=1. Setting fast=1 (the default) recognizes and supports NaN and infinite values.

• • -xclearwaterforest
  • 
  • PASS2_CXXFLAGS, PASS2_LDFLAGS

  • May generate instructions for processors that support the specified Intel processor or microarchitecture code name. Optimizes for the specified Intel processor or microarchitecture code name.

• • -flto
  • 
  • CXXOPTIMIZE, PASS1_LDFLAGS, PASS2_LDFLAGS

  • Performs link time optimizations, which is also known as Interprocedural Optimizations.

• • -qopt-mem-layout-trans=4
  • 
  • CXXOPTIMIZE, PASS1_LDFLAGS, PASS2_LDFLAGS

  • Controls the level of memory layout transformations performed by the compiler. This option can improve cache reuse and cache locality.

    • 0: Disables memory layout transformations. This is the same as specifying -qno-opt-mem-layout-trans
    • 1: Enable basic memory layout transformations like structure splitting, structure peeling, field inlining, field reordering, array field transpose, increase field alignment etc.
    • 2: Enable more memory layout transformations like advanced structure splitting. This is the same as specifying -qopt-mem-layout-trans
    • 3: Enable more memory layout transformations like copy-in/copy-out of structures for a region of code. You should only use this setting if your system has more than 4GB of physical memory per core.
    • 4: Compiler is more aggressive in using memory layout transformations. You should only use this setting if your system has more than 4GB of physical memory per core.
• • -O3
  • 
  • CXXOPTIMIZE

  • Enable O2 optimizations plus more aggressive optimizations, such as prefetching, scalar replacement, and loop and memory access transformations. Enable optimizations for maximum speed, such as:

    • Loop unrolling, including instruction scheduling
    • Code replication to eliminate branches
    • Padding the size of certain power-of-two arrays to allow more efficient cache use.
    
    

    On IA-32 and Intel EM64T processors, when O3 is used with options -ax or -x (Linux) or with options /Qax or /Qx (Windows), the compiler performs more aggressive data dependency analysis than for O2, which may result in longer compilation times. The O3 optimizations may not cause higher performance unless loop and memory access transformations take place. The optimizations may slow down code in some cases compared to O2 optimizations. The O3 option is recommended for applications that have loops that heavily use floating-point calculations and process large data sets.

  • Includes:
    • -O2
      • -O1
        • -funroll-loops
        • -fno-builtin
        • -mno-ieee-fp
        • -fomit-framepointer
        • -ffunction-sections
        • -ftz
• • -mfpmath=sse
  • 
  • CXXOPTIMIZE

  • Generate floating-point arithmetic for the selected unit. When set to "sse" use scalar floating-point instructions present in the SSE instruction set.

• • -funroll-loops
  • 
  • CXXOPTIMIZE

  • Tells the compiler the maximum number of times to unroll loops. For example -funroll-loops0 would disable unrolling of loops.

• • -pthread
  • 
  • EXTRA_CXXOPTIMIZE

  • Enable support for Posix Threads. Note that C++ programs using std::thread may require this flag.

• • -fiopenmp
  • 
  • Yes
  • EXTRA_CXXOPTIMIZE

  • Enable the compiler to generate multi-threaded code based on the OpenMP* directives.

• • -DSPEC_OPENMP
  • 
  • EXTRA_CXXOPTIMIZE

  • Definition of this macro indicates that compilation for parallel operation is enabled, and that any OpenMP directives or pragmas will be visible to the compiler. The behavior of this macro is overridden if -DSPEC_SUPPRESS_OPENMP also appears in the list of compilation flags.

• • -L/usr/local/jemalloc-5.3.0/lib
  • 
  • EXTRA_LIBS

  • Build time link path for libraries supplied with the compiler (for example, the qkmalloc library).

• • -ljemalloc
  • 
  • EXTRA_LIBS

  • Linker toggle to specify jemalloc linker library. See jemalloc.net for more information.

Benchmarks using both C and C++

801.xz_s

• • -m64
  • 
  • intel_icc,intel_icpc,intel_ifort,intel_icx,intel_icpx,intel_ifx
  • CC, CXX, LD

  • Compiles for a 64-bit (LP64) data model.

• • -std=c++17
  • 
  • intel_icx,intel_icpx
  • CXX, LD

  • Sets the language standard to the specified version, for example c18, c++17, f2008.

• • -std=c18
  • 
  • intel_icx,intel_icpx
  • CC

  • Sets the language standard to the specified version, for example c18, c++17, f2008.

• • -Wl,-z,muldefs
  • 
  • EXTRA_LDFLAGS

  • Enable SmartHeap and/or other library usage by forcing the linker to ignore multiple definitions if present

• • -Wl,-plugin-opt=-inline-threshold=1500
  • 
  • EXTRA_LDFLAGS

  • Controls the compiler's inlining threshold by adjusting the value passed as an argument

• • -fprofile-generate
  • 
  • PASS1_CFLAGS, PASS1_CXXFLAGS, PASS1_LDFLAGS

  • Instrument program for profiling for the first phase of two-phase profile guided optimization. This instrumentation gathers information about a program's execution paths and data values but does not gather information from hardware performance counters. The profile instrumentation also gathers data for optimizations which are unique to profile-feedback optimization.

• • -fprofile-use=default.profdata
  • 
  • PASS2_CFLAGS, PASS2_CXXFLAGS, PASS2_LDFLAGS

  • Instructs the compiler to produce a profile-optimized executable and merges available dynamic information.

• • -xCORE-AVX2
  • 
  • PASS1_CFLAGS, PASS1_CXXFLAGS, PASS1_LDFLAGS

  • Code is optimized for Intel(R) processors with support for AVX2 instructions. The resulting code may contain unconditional use of features that are not supported on other processors. This option also enables new optimizations in addition to Intel processor-specific optimizations including advanced data layout and code restructuring optimizations to improve memory accesses for Intel processors.

    Do not use this option if you are executing a program on a processor that is not an Intel processor. If you use this option on a non-compatible processor to compile the main program (in Fortran) or the function main() in C/C++, the program will display a fatal run-time error if they are executed on unsupported processors.

• • -ffp-model=fast
  • 
  • COPTIMIZE, CXXOPTIMIZE, PASS1_LDFLAGS, PASS2_LDFLAGS

  • Tells the compiler to use more aggressive optimizations when implementing floating-point calculations. These optimizations increase speed, but they may affect the accuracy or reproducibility of floating-point computations.

    Specifying fast is the same as specifying fast=1. Setting fast=1 (the default) recognizes and supports NaN and infinite values.

• • -xclearwaterforest
  • 
  • PASS2_CFLAGS, PASS2_CXXFLAGS, PASS2_LDFLAGS

  • May generate instructions for processors that support the specified Intel processor or microarchitecture code name. Optimizes for the specified Intel processor or microarchitecture code name.

• • -flto
  • 
  • COPTIMIZE, CXXOPTIMIZE, PASS1_LDFLAGS, PASS2_LDFLAGS

  • Performs link time optimizations, which is also known as Interprocedural Optimizations.

• • -qopt-mem-layout-trans=4
  • 
  • COPTIMIZE, CXXOPTIMIZE, PASS1_LDFLAGS, PASS2_LDFLAGS

  • Controls the level of memory layout transformations performed by the compiler. This option can improve cache reuse and cache locality.

    • 0: Disables memory layout transformations. This is the same as specifying -qno-opt-mem-layout-trans
    • 1: Enable basic memory layout transformations like structure splitting, structure peeling, field inlining, field reordering, array field transpose, increase field alignment etc.
    • 2: Enable more memory layout transformations like advanced structure splitting. This is the same as specifying -qopt-mem-layout-trans
    • 3: Enable more memory layout transformations like copy-in/copy-out of structures for a region of code. You should only use this setting if your system has more than 4GB of physical memory per core.
    • 4: Compiler is more aggressive in using memory layout transformations. You should only use this setting if your system has more than 4GB of physical memory per core.
• • -O3
  • 
  • COPTIMIZE, CXXOPTIMIZE

  • Enable O2 optimizations plus more aggressive optimizations, such as prefetching, scalar replacement, and loop and memory access transformations. Enable optimizations for maximum speed, such as:

    • Loop unrolling, including instruction scheduling
    • Code replication to eliminate branches
    • Padding the size of certain power-of-two arrays to allow more efficient cache use.
    
    

    On IA-32 and Intel EM64T processors, when O3 is used with options -ax or -x (Linux) or with options /Qax or /Qx (Windows), the compiler performs more aggressive data dependency analysis than for O2, which may result in longer compilation times. The O3 optimizations may not cause higher performance unless loop and memory access transformations take place. The optimizations may slow down code in some cases compared to O2 optimizations. The O3 option is recommended for applications that have loops that heavily use floating-point calculations and process large data sets.

  • Includes:
    • -O2
      • -O1
        • -funroll-loops
        • -fno-builtin
        • -mno-ieee-fp
        • -fomit-framepointer
        • -ffunction-sections
        • -ftz
• • -mfpmath=sse
  • 
  • COPTIMIZE, CXXOPTIMIZE

  • Generate floating-point arithmetic for the selected unit. When set to "sse" use scalar floating-point instructions present in the SSE instruction set.

• • -funroll-loops
  • 
  • COPTIMIZE, CXXOPTIMIZE

  • Tells the compiler the maximum number of times to unroll loops. For example -funroll-loops0 would disable unrolling of loops.

• • -fno-strict-aliasing
  • 
  • EXTRA_CFLAGS

  • Disable use of strict aliasing rules in optimizations.

• • -fiopenmp
  • 
  • Yes
  • EXTRA_COPTIMIZE, EXTRA_CXXOPTIMIZE

  • Enable the compiler to generate multi-threaded code based on the OpenMP* directives.

• • -DSPEC_OPENMP
  • 
  • EXTRA_COPTIMIZE, EXTRA_CXXOPTIMIZE

  • Definition of this macro indicates that compilation for parallel operation is enabled, and that any OpenMP directives or pragmas will be visible to the compiler. The behavior of this macro is overridden if -DSPEC_SUPPRESS_OPENMP also appears in the list of compilation flags.

• • -pthread
  • 
  • EXTRA_CXXOPTIMIZE

  • Enable support for Posix Threads. Note that C++ programs using std::thread may require this flag.

• • -L/usr/local/jemalloc-5.3.0/lib
  • 
  • EXTRA_LIBS

  • Build time link path for libraries supplied with the compiler (for example, the qkmalloc library).

• • -ljemalloc
  • 
  • EXTRA_LIBS

  • Linker toggle to specify jemalloc linker library. See jemalloc.net for more information.

817.flac_s

• • Same as 801.xz_s

821.gcc_s

• • -m64
  • 
  • intel_icc,intel_icpc,intel_ifort,intel_icx,intel_icpx,intel_ifx
  • CC, CXX, LD

  • Compiles for a 64-bit (LP64) data model.

• • -std=c++17
  • 
  • intel_icx,intel_icpx
  • CXX, LD

  • Sets the language standard to the specified version, for example c18, c++17, f2008.

• • -std=c18
  • 
  • intel_icx,intel_icpx
  • CC

  • Sets the language standard to the specified version, for example c18, c++17, f2008.

• • -Wl,-z,muldefs
  • 
  • EXTRA_LDFLAGS

  • Enable SmartHeap and/or other library usage by forcing the linker to ignore multiple definitions if present

• • -fprofile-generate
  • 
  • PASS1_CFLAGS, PASS1_CXXFLAGS, PASS1_LDFLAGS

  • Instrument program for profiling for the first phase of two-phase profile guided optimization. This instrumentation gathers information about a program's execution paths and data values but does not gather information from hardware performance counters. The profile instrumentation also gathers data for optimizations which are unique to profile-feedback optimization.

• • -fprofile-use=default.profdata
  • 
  • PASS2_CFLAGS, PASS2_CXXFLAGS, PASS2_LDFLAGS

  • Instructs the compiler to produce a profile-optimized executable and merges available dynamic information.

• • -xCORE-AVX2
  • 
  • PASS1_CFLAGS, PASS1_CXXFLAGS, PASS1_LDFLAGS

  • Code is optimized for Intel(R) processors with support for AVX2 instructions. The resulting code may contain unconditional use of features that are not supported on other processors. This option also enables new optimizations in addition to Intel processor-specific optimizations including advanced data layout and code restructuring optimizations to improve memory accesses for Intel processors.

    Do not use this option if you are executing a program on a processor that is not an Intel processor. If you use this option on a non-compatible processor to compile the main program (in Fortran) or the function main() in C/C++, the program will display a fatal run-time error if they are executed on unsupported processors.

• • -ffp-model=fast
  • 
  • COPTIMIZE, CXXOPTIMIZE, PASS1_LDFLAGS, PASS2_LDFLAGS

  • Tells the compiler to use more aggressive optimizations when implementing floating-point calculations. These optimizations increase speed, but they may affect the accuracy or reproducibility of floating-point computations.

    Specifying fast is the same as specifying fast=1. Setting fast=1 (the default) recognizes and supports NaN and infinite values.

• • -xclearwaterforest
  • 
  • PASS2_CFLAGS, PASS2_CXXFLAGS, PASS2_LDFLAGS

  • May generate instructions for processors that support the specified Intel processor or microarchitecture code name. Optimizes for the specified Intel processor or microarchitecture code name.

• • -flto
  • 
  • COPTIMIZE, CXXOPTIMIZE, PASS1_LDFLAGS, PASS2_LDFLAGS

  • Performs link time optimizations, which is also known as Interprocedural Optimizations.

• • -qopt-mem-layout-trans=4
  • 
  • COPTIMIZE, CXXOPTIMIZE, PASS1_LDFLAGS, PASS2_LDFLAGS

  • Controls the level of memory layout transformations performed by the compiler. This option can improve cache reuse and cache locality.

    • 0: Disables memory layout transformations. This is the same as specifying -qno-opt-mem-layout-trans
    • 1: Enable basic memory layout transformations like structure splitting, structure peeling, field inlining, field reordering, array field transpose, increase field alignment etc.
    • 2: Enable more memory layout transformations like advanced structure splitting. This is the same as specifying -qopt-mem-layout-trans
    • 3: Enable more memory layout transformations like copy-in/copy-out of structures for a region of code. You should only use this setting if your system has more than 4GB of physical memory per core.
    • 4: Compiler is more aggressive in using memory layout transformations. You should only use this setting if your system has more than 4GB of physical memory per core.
• • -O3
  • 
  • COPTIMIZE, CXXOPTIMIZE

  • Enable O2 optimizations plus more aggressive optimizations, such as prefetching, scalar replacement, and loop and memory access transformations. Enable optimizations for maximum speed, such as:

    • Loop unrolling, including instruction scheduling
    • Code replication to eliminate branches
    • Padding the size of certain power-of-two arrays to allow more efficient cache use.
    
    

    On IA-32 and Intel EM64T processors, when O3 is used with options -ax or -x (Linux) or with options /Qax or /Qx (Windows), the compiler performs more aggressive data dependency analysis than for O2, which may result in longer compilation times. The O3 optimizations may not cause higher performance unless loop and memory access transformations take place. The optimizations may slow down code in some cases compared to O2 optimizations. The O3 option is recommended for applications that have loops that heavily use floating-point calculations and process large data sets.

  • Includes:
    • -O2
      • -O1
        • -funroll-loops
        • -fno-builtin
        • -mno-ieee-fp
        • -fomit-framepointer
        • -ffunction-sections
        • -ftz
• • -mfpmath=sse
  • 
  • COPTIMIZE, CXXOPTIMIZE

  • Generate floating-point arithmetic for the selected unit. When set to "sse" use scalar floating-point instructions present in the SSE instruction set.

• • -funroll-loops
  • 
  • COPTIMIZE, CXXOPTIMIZE

  • Tells the compiler the maximum number of times to unroll loops. For example -funroll-loops0 would disable unrolling of loops.

• • -fno-strict-aliasing
  • 
  • EXTRA_CFLAGS

  • Disable use of strict aliasing rules in optimizations.

• • -fiopenmp
  • 
  • Yes
  • EXTRA_COPTIMIZE, EXTRA_CXXOPTIMIZE

  • Enable the compiler to generate multi-threaded code based on the OpenMP* directives.

• • -DSPEC_OPENMP
  • 
  • EXTRA_COPTIMIZE, EXTRA_CXXOPTIMIZE

  • Definition of this macro indicates that compilation for parallel operation is enabled, and that any OpenMP directives or pragmas will be visible to the compiler. The behavior of this macro is overridden if -DSPEC_SUPPRESS_OPENMP also appears in the list of compilation flags.

• • -pthread
  • 
  • EXTRA_CXXOPTIMIZE

  • Enable support for Posix Threads. Note that C++ programs using std::thread may require this flag.

• • -L/usr/local/jemalloc-5.3.0/lib
  • 
  • EXTRA_LIBS

  • Build time link path for libraries supplied with the compiler (for example, the qkmalloc library).

• • -ljemalloc
  • 
  • EXTRA_LIBS

  • Linker toggle to specify jemalloc linker library. See jemalloc.net for more information.

823.llvm_s

• • Same as 821.gcc_s

829.abc_s

• • basepeak = yes

834.vpr_s

• • basepeak = yes

835.gem5_s

• • Same as 801.xz_s

838.diamond_s

• • Same as 801.xz_s

846.minizinc_s

• • Same as 801.xz_s