Flip-flops are generally modelled in behavioural code using non-blocking
assignments. This change makes the synthesised code behave the same as
the behavioural code. It's a more realistic model of a real flip-flop
too, which will always have some clock-to-output delay.
The .scope needs to be aware of return types so that the %call/vec4
function knows how to intialize the return value. We also need to
extend the %ret/vec4 to support writing parts of the return value.
Create The %callf/* opcodes to invoke user defined functions in a
more specialized way. This allows for some sanity checking on the
way, and also is a step towards keeping return values on stacks.
"# include <string>" was added so "Microsoft Visual Studio Express 2015 RC Web" could compile it without error. "static void operator delete[](void*); was preprocessed so "Microsoft Visual Studio Express 2015 RC Web" could link it without error for a function not yet implemented.
"child->delay_delete = 1;" was added, for when building with "Microsoft Visual Studio Express 2015 RC Web" in DEBUG mode, so that pr2909555.v would pass with -strict, otherwise it would cause memory access error will trying to access the previously deleted "child" variable.
In the special case that a net is attached to an island port, values
driven onto the net via the VPI must go to the functor, not the filter,
so that they propagate through the island.
When putting a value onto a wire, the value needs to be sent to the
filter, not the functor (the functor may be part of the expression
that drives the wire).
Force and release weren't implemented properly (or at all in the
case of real values). They need to behave the same as the force
and release operations in vthread.cc.
vvp_net_t::force_vec4 propagates all bits of the forced value passed
to it, regardless of the mask value. I can't see any way to fix this
directly, so instead make sure anything that calls force_vec4 sets
the unforced bits of the passed value to the correct value.
This forces <stdout> to be unbuffered. This is useful when using the
mintty terminal emulator in Windows (as used by MSYS2 and CygWin),
which identifies as a pipe, not a tty.
Removed obsolete -m32 and -ivl options from iverilog-vpi man page
and revised description of -mingw option. Also removed duplicate
descriptions of --cflags, --ldflags, and --ldlibs options. Updated
link to main iverilog web page in all man pages.
Defining __USE_MINGW_ANSI_STDIO=1 provides C99 compatible printf
and scanf routines, which avoids the need for workarounds for the
various failings of the Microsoft C runtime library.
The Microsoft C runtime does not support the %zu and %zd formats.
Previously these were replaced with %u and %d, but for 64-bit we
need to use %llu and %lld.
__vpiVThrVec4Stack::vpi_get_value_int_ was always treating the thread variable
as unsigned, rather than observing the value of __vpiVThrVec4Stack::signed_flag_.
Not sure why this was done - none of the regression tests broke when I changed
this.
A disable statement can terminate a thread whilst it still has
local variables on the stack (e.g. the loop counter for a repeat
statement). We need to clear the thread stacks when this happens.
Using a UL constant in a unit64_t context does not work on a 32-bit
machine since UL is 32-bits. Instead create uint64_t constants using
static casts and the appropriate bit operators.
These bypass the vec4 stack in some common cases, saving instructions
and vec4 manipulations.
Also, minor improvement to the %flag/set/vec4 statement.
Kill a few warnings.
- Have %pushi/vec4 handle some special cases optimally.
- Eliminate some duplicated method calls in %load/vec4.
- Optimize the vvp_vector4_t::copy_from_ method by inlining
some parts.
The code to get the correct modpath delay for a given edge had the X and Z
entries swapped.
When putting a delay from the VPI the 2 delay to twelve delay mapping was
incorrect and the to/from X delays were also not being calculated correctly.
This adds the runtime support for class properties that are classes
to be arrayed. Add a means to define the dimensions of a property
in the vvp format, and add functions for setting/extracting elements
of a property.
This goes all the way down to the vvp level, where we create support
for arrays of objects, generate the new code in the -tvvp code
generator, and elaborate the arrays in the first place.
Internally, treat the "$" as a special expression type that takes
as an argument the signal that is being indexed. In the vvp target,
use the $last system function to implement this.
This works by translating it to a $size() system function call.
The $size function is already implemented for dynamic queues and
it is easy enough to expand it for queues.
When for example assigning to foo[<x>] within a contitional, and
doing synthesis, we need to create a NetSubstitute device to manage
the l-value bit selects.
Testing with 32-bit clang 3.3, with additional compiler flags
-Wsign-compare -Wundef
this patch eliminates the following warnings:
config.h💯6: warning: 'UINT64_T_AND_ULONG_SAME' is not defined, evaluates to 0 [-Wundef]
vcd_priv2.cc:233:12: warning: duplicate 'extern' declaration specifier [-Wduplicate-decl-specifier]
parse.cc:6496:9: warning: comparison of 0 <= unsigned expression is always true [-Wtautological-compare]
parse.cc:6499:13: warning: comparison of 0 <= unsigned expression is always true [-Wtautological-compare]
parse.cc:6502:9: warning: comparison of 0 <= unsigned expression is always true [-Wtautological-compare]
parse.cc:6510:53: warning: comparison of integers of different signs: 'const unsigned int' and 'int' [-Wsign-compare]
Changing the vlltype elements from unsigned to int reconciles their
type with the native bison YYLTYPE structure.
Before this patch, WARNING_FLAGS applied to both C and C++,
and WARNING_FLAGS_CXX applied to C++ only.
This patch adds a WARNING_FLAGS_CC that applies to C only.
That change should be generally useful; in particular the C
code is almost ready for -Wstrict-prototypes, which does not
apply to C++.
-Wextra (or -W) used to only apply to C++ via WARNING_FLAGS_CXX.
This patch moves it to WARNING_FLAGS, to apply to both C and C++.
Unfortunately, that triggers a ton of warnings.
For now, cover most of the new warnings up by adding
-Wno-unused -Wno-sign-compare -Wno-type-limits
to WARNING_FLAGS_CC. In the long run, I want to change the C coding
style, and take off these disable-warning flags. But those changes
can dribble in as separate commits; this patch is big enough already.
Actually fix a couple missing-field-initializers in libveriuser/veriusertfs.c.
119 formal void parameters added to keep -Wstrict-prototypes happy.
Process found one real missing prototype in vpi/vcd_priv.h:
EXTERN void vcd_names_delete(struct vcd_names_list_s*tab);
8 such warnings left, all in Tony's code
This generates an EQZ LPM device that carries the case-z-ness to
the code generator.
Also add to the vvp code generator support for the EQZ device so
that the synthesis results can be simulated.
Account for the wildcard devices in the sizer.
Second try cleaning up cast-alignment problems surrounding need_result_buf().
Clang gave a bunch of warnings like
vvp/vpi_const.cc:196:34: warning: cast from 'char *' to 'p_vpi_vecval' (aka 't_vpi_vecval *') increases required alignment from 1 to 4 [-Wcast-align]
This version is verbose and changes the prototype for need_result_buf().
But it is semantically (c++) correct, and makes need_result_buf() feel like malloc().
This function was apparently not well tested, because any use of
acc_handle_object() triggered a use of vpi_handle_by_name that was
buggy.
The implementation was awkwardly written, to parts of it were redone.
%exec_ufunc assumed that because a function can never block, a call to
vthread_run() on the function code would only return when the final %end
instruction had been executed. This is not true if the function contains
a named block, which will be executed via a %fork instruction, allowing
the main function thread to suspend after a %join instruction. The fix
is to break %exec_ufunc into two instructions, the first setting the
function inputs and executing the function code, the second collecting
the function result. This provides the opportunity for the parent thread
to suspend after the %exec_ufunc instruction until all its children have
completed.
When performing the initial assignment for a procedural continuous
assignment, any previous continuous assignment to the destination
signal must be unlinked first, otherwise the initial value for the
assignment will propagate to any other nets that are driven by the
original source signal.
In the case that the RHS of a procedural continuous assignment is a simple
vector that is wider than the LHS, changes to the RHS vector cause the
entire vector to be sent to port 1 of the LHS vvp_fun_signal object. This
vector needs to be coerced to the size of the LHS. Note that this is a
stopgap fix until vvp handles arbitrary expressions on the RHS of a
procedural continuous assignment.
Signed vector power operations were being implemented using the double
pow() function. This gave inaccurate results when the operands or
result were not exactly representable by a 64-bit floating point number.
The vvp_vector2_t::pow() function is recursive, and performs a multiplication
operation on each step. The multiplication operator was expanding the result
vector to accomodate the maximum possible result value for the given operand
vectors, thus causing the execution time of the power operation to be
exponentially proportional to the exponent value. Both in this case and
in general, it is unnecessary for the multiplication result vector to be
expanded, as the compiler has already determined the required vector width
during elaboration, and sizes the operand vectors to match.
The vvp_vector2_t constructor that takes a vvp_vector4_t value was
documented as creating a NaN value if the supplied vector contained
any X or Z bits, but instead used the standard Verilog 4-state to
2-state conversion semantics (X or Z translate to 0). I've added an
optional second parameter to the constructor to allow the user to
choose which semantics they want, as both are needed.
Larry Doolittle
Martin Whitaker
Stephen Williams
Maciej Suminski
Cary R
Christian Taedcke
Frederick C. Kurz
Martin Whitaker