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SPDX-License-Identifier: CC-BY-SA-4.0
copyrights:
- Copyright (C) 2020 embedded brains GmbH & Co. KG
enabled-by: true
functional-type: function
links:
- role: interface-function
uid: ../if/predict-false
rationale: |
Example: ``if ( ${../if/predict-false:/name}( -1 == i ) ) { ... }``.
The GNU C compiler uses this information for branch optimization.
``builtin-expect-probability`` defaults to 90%.
references: []
requirement-type: functional
text: |
When the code is compiled with the GNU C compiler,
and the ${../if/predict-false:/name} macro is used as a conditional
in ``if``-expressions and loop expressions,
and ${../if/predict-false:/params[0]/name} after undergoing all possible C
pre-processor substitutions is an integral expression,
the macro shall cause the compiler to assume that by the percentage of
cases defined by ``builtin-expect-probability`` the expression evaluates
to 0.
type: requirement
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