ARCH
The ARCH option specifies the machine
architecture for which the executable program instructions are to
be generated.
Default is: 
ARCH(10)
Abbreviations are: None
If you specify a higher ARCH level, the compiler generates code
that uses newer and faster instructions. Your application might abend if it runs on a processor with
an architecture level lower than what you specified with the ARCH option. Use the
ARCH level that matches the lowest machine architecture where your application
runs, including any disaster recovery (DR) machines.
- 10
- Produces code that uses instructions available on the 2827-xxx (IBM®
zEnterprise® EC12) and 2828-xxx (IBM
zEnterprise BC12) models in IBM z/Architecture® mode. Specifically, these
ARCH(10)machines and their follow-ons add instructions supported by the following facilities:- Execution-Hint Facility
- Load-and-Trap Facility
- Miscellaneous-Instructions-Extension Facility
- Transactional-Execution Facility
- Enhanced Decimal Floating Point Facility that enables more efficient conversions between zoned decimal data items and decimal floating point data items. Instead of converting zoned decimal data items to packed decimal data items to perform arithmetic when conditions permit it and the optimization level is greater than 0, the compiler converts zoned decimal data items directly to decimal floating point data items, and then back again to zoned decimal data items after the computations are complete.
- 11
- Produces code that uses instructions available on 2964-xxx (IBM
z13®) and 2965-xxx (IBM
z13s®) models in IBM z/Architecture mode. Specifically, these
ARCH(11)machines and their follow-ons add instructions supported by the following facilities:- Enhanced Decimal Floating Point Facility that enables more efficient conversions between packed-decimal data items and decimal floating point intermediate result data items when the surrounding conditions are optimal and the optimization level is greater than 0.
- Exploitation of the Vector Extension Facility (SIMD) instructions for some
INSPECT REPLACINGandINSPECT TALLYINGstatements.To use the Vector Extension Facility (SIMD) instructions, the code must be executed on a machine running on z/OS® 2.2, or z/OS 2.1 with the PTFs for APARs OA43803 and PI12412 installed.
- 12
- Produces code that uses instructions available on 3906-xxx (IBM z14) and 3907-xxx (IBM z14 ZR1) models in IBM z/Architecture mode.
Specifically, these
ARCH(12)machines and their follow-ons add instructions supported by the Vector Packed Decimal Facility, which accelerates packed and zoned decimal computation by storing intermediate results in vector registers instead of in memory. - 13
- Produces code that uses instructions available on the 8561-xxx (IBM
z15) and 8562-xxx (IBM
z15 T02) models in IBM z/Architecture mode. Specifically, these
ARCH(13)machines and their follow-ons add instructions supported by the following facilities:- Vector Packed Decimal Enhancement Facility
- Vector-Enhancements Facility 2
- Miscellaneous Instruction-Extensions-Facility 3
- Aligned vector load/store hints
- 14
- Produces code that uses instructions available on the 3931-xxxx (IBM z16) model in IBM
z/Architecture mode.Specifically, this
ARCH(14)machine and its follow-ons add instructions supported by the new Vector Packed Decimal Enhancement Facility 2. This new facility adds performance improvements for COBOL programs that contain one or more of the following types of statements:- Exponentiation operations on packed or zoned decimal data items where the exponent is declared with one or more fractional digits
- Arithmetic statements involving mixed decimal and floating-point data items
- Statements using numeric-edited data items
ARCH level includes the facilities of the lower
ARCH levels. For example, ARCH(14)
includes all the facilities of the lower ARCH levels.For more information about these facilities, see IBM z/Architecture Principles of Operation.