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Diffstat (limited to 'CodingReadme')
| -rw-r--r-- | CodingReadme | 33 |
1 files changed, 24 insertions, 9 deletions
diff --git a/CodingReadme b/CodingReadme index bdadf821d..2349b2ee2 100644 --- a/CodingReadme +++ b/CodingReadme @@ -1,5 +1,10 @@ +This file contains some very brief documentation on things like programming APIs. +Also consult the Yosys manual and the section about programming in the presentation. +(Both can be downloaded as PDF from the yosys webpage.) + +--snip-- only the lines below this mark are included in the yosys manual --snip-- Getting Started =============== @@ -42,13 +47,21 @@ defined when "kernel/yosys.h" is included and USING_YOSYS_NAMESPACE is used. 1. Yosys Container Classes Yosys uses dict<K, T> and pool<T> as main container classes. dict<K, T> is -essentially a replacement for std::unordered_map<K, T> and pool<T> is -essentially a replacement for std::unordered_set<T>. The main differences are: +essentially a replacement for std::unordered_map<K, T> and pool<T> is a +replacement for std::unordered_set<T>. The main characteristics are: - dict<K, T> and pool<T> are about 2x faster than the std containers - references to elements in a dict<K, T> or pool<T> are invalidated by - insert operations (just like you are used from std::vector<T>). + insert and remove operations (similar to std::vector<T> on push_back()). + + - some iterators are invalidated by erase(). specifically, iterators + that have not passed the erased element yet are invalidated. (erase() + itself returns valid iterator to the next element.) + + - no iterators are invalidated by insert(). elements are inserted at + begin(). i.e. only a new iterator that starts at begin() will see the + inserted elements. - dict<K, T> and pool<T> will have the same order of iteration across all compilers and architectures. @@ -97,12 +110,12 @@ namespace. 4. SigMap and other Helper Classes There are a couple of additional helper classes that are in wide use -in Yosys. Most importantly there is SigMap (declared in kernel.sigtools.h). +in Yosys. Most importantly there is SigMap (declared in kernel/sigtools.h). -When a design has many wires in it that are connected to each other, then -a single signal bit can have multiple valid names. The SigMap object can -be used to map SigSpecs or SigBits to unique SigSpecs and SigBits that -consitently only uses one wire from a group of connected wires. For example: +When a design has many wires in it that are connected to each other, then a +single signal bit can have multiple valid names. The SigMap object can be used +to map SigSpecs or SigBits to unique SigSpecs and SigBits that consitently +only use one wire from such a group of connected wires. For example: SigBit a = module->addWire(NEW_ID); SigBit b = module->addWire(NEW_ID); @@ -162,7 +175,7 @@ C++ Langugage ------------- Yosys is written in C++11. At the moment only constructs supported by -gcc 4.6 is allowed in Yosys code. This will change in future releases. +gcc 4.6 are allowed in Yosys code. This will change in future releases. In general Yosys uses "int" instead of "size_t". To avoid compiler warnings for implicit type casts, always use "GetSize(foobar)" instead @@ -171,6 +184,8 @@ of "foobar.size()". (GetSize() is defined in kernel/yosys.h) Use range-based for loops whenever applicable. +--snap-- only the lines above this mark are included in the yosys manual --snap-- + Creating the Visual Studio Template Project =========================================== |