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Catherine a33acb7cd9 cxxrtl: refactor the formatter and use a closure. This commit achieves three roughly equally important goals: 1. To bring the rendering code in kernel/fmt.cc and in cxxrtl.h as close together as possible, with an ideal of only having the bigint library as the difference between the render functions. 2. To make the treatment of `$time` and `$realtime` in CXXRTL closer to the Verilog semantics, at least in the formatting code. 3. To change the code generator so that all of the `$print`-to-`string` conversion code is contained inside of a closure. There are two reasons to aim for goal (3): a. Because output redirection through definition of a global ostream object is neither convenient nor useful for environments where the output is consumed by other code rather than being printed on a terminal. b. Because it may be desirable to, in some cases, ignore the `$print` cells that are present in the netlist based on a runtime decision. This is doubly true for an upcoming `$check` cell implementing assertions, since failing a `$check` would by default cause a crash.	2024-01-16 16:35:51 +00:00
..
cxxrtl	cxxrtl: refactor the formatter and use a closure.	2024-01-16 16:35:51 +00:00
README.txt	cxxrtl: reorganize runtime component files.	2023-11-28 15:32:36 +00:00

Catherine a33acb7cd9 cxxrtl: refactor the formatter and use a closure.

This commit achieves three roughly equally important goals:
1. To bring the rendering code in kernel/fmt.cc and in cxxrtl.h as close
   together as possible, with an ideal of only having the bigint library
   as the difference between the render functions.
2. To make the treatment of `$time` and `$realtime` in CXXRTL closer to
   the Verilog semantics, at least in the formatting code.
3. To change the code generator so that all of the `$print`-to-`string`
   conversion code is contained inside of a closure.

There are two reasons to aim for goal (3):
a. Because output redirection through definition of a global ostream
   object is neither convenient nor useful for environments where
   the output is consumed by other code rather than being printed on
   a terminal.
b. Because it may be desirable to, in some cases, ignore the `$print`
   cells that are present in the netlist based on a runtime decision.
   This is doubly true for an upcoming `$check` cell implementing
   assertions, since failing a `$check` would by default cause a crash.

2024-01-16 16:35:51 +00:00

cxxrtl

cxxrtl: refactor the formatter and use a closure.

2024-01-16 16:35:51 +00:00

README.txt

cxxrtl: reorganize runtime component files.

2023-11-28 15:32:36 +00:00

README.txt

This directory contains the runtime components of CXXRTL and should be placed on the include path
when building the simulation using the `-I${YOSYS}/backends/cxxrtl/runtime` option. These components
are not used in the Yosys binary; they are only built as a part of the simulation binary.

The interfaces declared in `cxxrtl_capi*.h` contain the stable C API. These interfaces will not be
changed in backward-incompatible ways unless no other option is available, and any breaking changes
will be made in a way that causes the downstream code to fail in a visible way. The ABI of these
interfaces is considered stable as well, and it will not use features complicating its use via
libraries such as libffi or ctypes.

The implementations in `cxxrtl_capi*.cc` are considered private; they are still placed in the include
path to enable build-system-less builds (where the CXXRTL runtime component is included in the C++
file of the simulation toplevel).

The interfaces declared in `cxxrtl*.h` (without `capi`) are unstable and may change without notice.

For clarity, all of the files in this directory and its subdirectories have unique names regardless
of the directory where they are placed.