Copyright © 2016 Intel Corporation. All Rights Reserved.
![[user]](https://www.spec.org/auto/cpu2026/images/user.png)
Invoke the Intel oneAPI DPC++ C compiler.
Invoke the Intel oneAPI DPC++ C++ compiler.
Invoke the Intel oneAPI DPC++ C++ compiler.
Invoke the Intel oneAPI DPC++ C compiler.
![[suite]](https://www.spec.org/auto/cpu2026/images/suite.png)
This option is used to indicate that the host system's integers are 32-bits wide, and longs and pointers are 64-bits wide. Not all benchmarks recognize this macro, but the preferred practice for data model selection applies the flags to all benchmarks; this flag description is a placeholder for those benchmarks that do not recognize this macro.
This option is used to indicate that the host system's integers are 32-bits wide, and longs and pointers are 64-bits wide. Not all benchmarks recognize this macro, but the preferred practice for data model selection applies the flags to all benchmarks; this flag description is a placeholder for those benchmarks that do not recognize this macro.
This option is used to indicate that the host system's integers are 32-bits wide, and longs and pointers are 64-bits wide. Not all benchmarks recognize this macro, but the preferred practice for data model selection applies the flags to all benchmarks; this flag description is a placeholder for those benchmarks that do not recognize this macro.
This option is used to indicate that the host system's integers are 32-bits wide, and longs and pointers are 64-bits wide. Not all benchmarks recognize this macro, but the preferred practice for data model selection applies the flags to all benchmarks; this flag description is a placeholder for those benchmarks that do not recognize this macro.
This option is used to indicate that the host system's integers are 32-bits wide, and longs and pointers are 64-bits wide. Not all benchmarks recognize this macro, but the preferred practice for data model selection applies the flags to all benchmarks; this flag description is a placeholder for those benchmarks that do not recognize this macro.
This option is used to indicate that the host system's integers are 32-bits wide, and longs and pointers are 64-bits wide. Not all benchmarks recognize this macro, but the preferred practice for data model selection applies the flags to all benchmarks; this flag description is a placeholder for those benchmarks that do not recognize this macro.
This option is used to indicate that the host system's integers are 32-bits wide, and longs and pointers are 64-bits wide. Not all benchmarks recognize this macro, but the preferred practice for data model selection applies the flags to all benchmarks; this flag description is a placeholder for those benchmarks that do not recognize this macro.
This option is used to indicate that the host system's integers are 32-bits wide, and longs and pointers are 64-bits wide. Not all benchmarks recognize this macro, but the preferred practice for data model selection applies the flags to all benchmarks; this flag description is a placeholder for those benchmarks that do not recognize this macro.
This option is used to indicate that the host system's integers are 32-bits wide, and longs and pointers are 64-bits wide. Not all benchmarks recognize this macro, but the preferred practice for data model selection applies the flags to all benchmarks; this flag description is a placeholder for those benchmarks that do not recognize this macro.
This option is used to indicate that the host system's integers are 32-bits wide, and longs and pointers are 64-bits wide. Not all benchmarks recognize this macro, but the preferred practice for data model selection applies the flags to all benchmarks; this flag description is a placeholder for those benchmarks that do not recognize this macro.
This option is used to indicate that the host system's integers are 32-bits wide, and longs and pointers are 64-bits wide. Not all benchmarks recognize this macro, but the preferred practice for data model selection applies the flags to all benchmarks; this flag description is a placeholder for those benchmarks that do not recognize this macro.
This option is used to indicate that the host system's integers are 32-bits wide, and longs and pointers are 64-bits wide. Not all benchmarks recognize this macro, but the preferred practice for data model selection applies the flags to all benchmarks; this flag description is a placeholder for those benchmarks that do not recognize this macro.
This option is used to indicate that the host system's integers are 32-bits wide, and longs and pointers are 64-bits wide. Not all benchmarks recognize this macro, but the preferred practice for data model selection applies the flags to all benchmarks; this flag description is a placeholder for those benchmarks that do not recognize this macro.
Compiles for a 64-bit (LP64) data model.
Sets the language standard to the specified version, for example c18, c++17, f2008.
Enable SmartHeap and/or other library usage by forcing the linker to ignore multiple definitions if present
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.
Specifies preferred vector width for auto-vectorization. Defaults to 'none' which allows target specific decisions.
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:
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.
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.
For Intel compiler options ffp-model=fast and fp-model=fast are interchangeable.
Performs link time optimizations, which is also known as Interprocedural Optimizations.
Generate floating-point arithmetic for selected unit unit. Here use scalar floating-point instructions present in the SSE instruction set
Tells the compiler the maximum number of times to unroll loops. For example -funroll-loops0 would disable unrolling of loops.
Controls the level of memory layout transformations performed by the compiler. This option can improve cache reuse and cache locality.
Enable the compiler to generate multi-threaded code based on the OpenMP* directives.
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.
Build time link path for libraries supplied with the compiler (for example, the qkmalloc library).
Linker toggle to specify jemalloc linker library. See jemalloc.net for more information.
Compiles for a 64-bit (LP64) data model.
Sets the language standard to the specified version, for example c18, c++17, f2008.
Enable SmartHeap and/or other library usage by forcing the linker to ignore multiple definitions if present
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.
Specifies preferred vector width for auto-vectorization. Defaults to 'none' which allows target specific decisions.
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:
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.
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.
For Intel compiler options ffp-model=fast and fp-model=fast are interchangeable.
Performs link time optimizations, which is also known as Interprocedural Optimizations.
Generate floating-point arithmetic for selected unit unit. Here use scalar floating-point instructions present in the SSE instruction set
Tells the compiler the maximum number of times to unroll loops. For example -funroll-loops0 would disable unrolling of loops.
Controls the level of memory layout transformations performed by the compiler. This option can improve cache reuse and cache locality.
Enable the compiler to generate multi-threaded code based on the OpenMP* directives.
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.
Build time link path for libraries supplied with the compiler (for example, the qkmalloc library).
Linker toggle to specify jemalloc linker library. See jemalloc.net for more information.
Compiles for a 64-bit (LP64) data model.
Sets the language standard to the specified version, for example c18, c++17, f2008.
Enable SmartHeap and/or other library usage by forcing the linker to ignore multiple definitions if present
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.
Specifies preferred vector width for auto-vectorization. Defaults to 'none' which allows target specific decisions.
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:
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.
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.
For Intel compiler options ffp-model=fast and fp-model=fast are interchangeable.
Performs link time optimizations, which is also known as Interprocedural Optimizations.
Generate floating-point arithmetic for selected unit unit. Here use scalar floating-point instructions present in the SSE instruction set
Tells the compiler the maximum number of times to unroll loops. For example -funroll-loops0 would disable unrolling of loops.
Controls the level of memory layout transformations performed by the compiler. This option can improve cache reuse and cache locality.
Enable support for Posix Threads. Note that C++ programs using std::thread may require this flag.
Build time link path for libraries supplied with the compiler (for example, the qkmalloc library).
Linker toggle to specify jemalloc linker library. See jemalloc.net for more information.
Compiles for a 64-bit (LP64) data model.
Sets the language standard to the specified version, for example c18, c++17, f2008.
Enable SmartHeap and/or other library usage by forcing the linker to ignore multiple definitions if present
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.
Specifies preferred vector width for auto-vectorization. Defaults to 'none' which allows target specific decisions.
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:
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.
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.
For Intel compiler options ffp-model=fast and fp-model=fast are interchangeable.
Performs link time optimizations, which is also known as Interprocedural Optimizations.
Generate floating-point arithmetic for selected unit unit. Here use scalar floating-point instructions present in the SSE instruction set
Tells the compiler the maximum number of times to unroll loops. For example -funroll-loops0 would disable unrolling of loops.
Controls the level of memory layout transformations performed by the compiler. This option can improve cache reuse and cache locality.
Build time link path for libraries supplied with the compiler (for example, the qkmalloc library).
Linker toggle to specify jemalloc linker library. See jemalloc.net for more information.
Compiles for a 64-bit (LP64) data model.
Sets the language standard to the specified version, for example c18, c++17, f2008.
Sets the language standard to the specified version, for example c18, c++17, f2008.
Enable SmartHeap and/or other library usage by forcing the linker to ignore multiple definitions if present
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.
Specifies preferred vector width for auto-vectorization. Defaults to 'none' which allows target specific decisions.
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:
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.
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.
For Intel compiler options ffp-model=fast and fp-model=fast are interchangeable.
Performs link time optimizations, which is also known as Interprocedural Optimizations.
Generate floating-point arithmetic for selected unit unit. Here use scalar floating-point instructions present in the SSE instruction set
Tells the compiler the maximum number of times to unroll loops. For example -funroll-loops0 would disable unrolling of loops.
Controls the level of memory layout transformations performed by the compiler. This option can improve cache reuse and cache locality.
Enable support for Posix Threads. Note that C++ programs using std::thread may require this flag.
Build time link path for libraries supplied with the compiler (for example, the qkmalloc library).
Linker toggle to specify jemalloc linker library. See jemalloc.net for more information.
Compiles for a 64-bit (LP64) data model.
Sets the language standard to the specified version, for example c18, c++17, f2008.
Sets the language standard to the specified version, for example c18, c++17, f2008.
Enable SmartHeap and/or other library usage by forcing the linker to ignore multiple definitions if present
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.
Specifies preferred vector width for auto-vectorization. Defaults to 'none' which allows target specific decisions.
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:
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.
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.
For Intel compiler options ffp-model=fast and fp-model=fast are interchangeable.
Performs link time optimizations, which is also known as Interprocedural Optimizations.
Generate floating-point arithmetic for selected unit unit. Here use scalar floating-point instructions present in the SSE instruction set
Tells the compiler the maximum number of times to unroll loops. For example -funroll-loops0 would disable unrolling of loops.
Controls the level of memory layout transformations performed by the compiler. This option can improve cache reuse and cache locality.
Build time link path for libraries supplied with the compiler (for example, the qkmalloc library).
Linker toggle to specify jemalloc linker library. See jemalloc.net for more information.
This section contains descriptions of flags that were included implicitly by other flags, but which do not have a permanent home at SPEC.
Enable optimizations for speed. This is the generally recommended
optimization level. This option also enables:
- Inlining of intrinsics
- Intra-file interprocedural optimizations, which include:
- inlining
- constant propagation
- forward substitution
- routine attribute propagation
- variable address-taken analysis
- dead static function elimination
- removal of unreferenced variables
- The following capabilities for performance gain:
- constant propagation
- copy propagation
- dead-code elimination
- global register allocation
- global instruction scheduling and control speculation
- loop unrolling
- optimized code selection
- partial redundancy elimination
- strength reduction/induction variable simplification
- variable renaming
- exception handling optimizations
- tail recursions
- peephole optimizations
- structure assignment lowering and optimizations
- dead store elimination
Enable optimizations for speed and disables some optimizations that increase code size and affect speed.
To limit code size, this option:
The O1 option may improve performance for applications with very large code size, many branches, and execution time not dominated by code within loops.
-O1 sets the following options:Tells the compiler the maximum number of times to unroll loops. For example -funroll-loops0 would disable unrolling of loops.
-fno-builtin disables inline expansion for all intrinsic functions.
This option trades off floating-point precision for speed by removing the restriction to conform to the IEEE standard.
EBP is used as a general-purpose register in optimizations.
Places each function in its own COMDAT section.
Flushes denormal results to zero.
Flag description origin markings:
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Indicates that the flag description came from the user flags file. |
|
Indicates that the flag description came from the suite-wide flags file. |
![[benchmark]](https://www.spec.org/auto/cpu2026/images/benchmark.png) |
Indicates that the flag description came from a per-benchmark flags file. |
For questions about the meanings of these flags, please contact the tester.
For other inquiries, please contact info@spec.org
Copyright 2026 Standard Performance Evaluation Corporation
Tested with SPEC CPU®2026 v0.902.0.
Report generated on 2026-05-04 23:28:53 by SPEC CPU®2026 flags formatter (5b352a85).