Commit Graph

139 Commits

Author SHA1 Message Date
Rupert Swarbrick ee2b5b7ed1 Generate an RTLIL representation of bind constructs
This code now takes the AST nodes of type AST_BIND and generates a
representation in the RTLIL for them.

This is a little tricky, because a binding of the form:

    bind baz foo_t foo_i (.arg (1 + bar));

means "make an instance of foo_t called foo_i, instantiate it inside
baz and connect the port arg to the result of the expression 1+bar".
Of course, 1+bar needs a cell for the addition. Where should that cell
live?

With this patch, the Binding structure that represents the construct
is itself an AST::AstModule module. This lets us put the adder cell
inside it. We'll pull the contents out and plonk them into 'baz' when
we actually do the binding operation as part of the hierarchy pass.

Of course, we don't want RTLIL::Binding to contain an
AST::AstModule (since kernel code shouldn't depend on a frontend), so
we define RTLIL::Binding as an abstract base class and put the
AST-specific code into an AST::Binding subclass. This is analogous to
the AST::AstModule class.
2021-08-13 17:11:35 -06:00
Marcelina Kościelnicka 8bdc019730 verilog: Emit $meminit_v2 cell.
Fixes #2447.
2021-07-28 23:18:38 +02:00
Rupert Swarbrick 414154dd27 Add support for parsing the SystemVerilog 'bind' construct
This doesn't do anything useful yet: the patch just adds support for
the syntax to the lexer and parser and adds some tests to check the
syntax parses properly. This generates AST nodes, but doesn't yet
generate RTLIL.

Since our existing hierarchical_identifier parser doesn't allow bit
selects (so you can't do something like foo[1].bar[2].baz), I've also
not added support for a trailing bit select (the "constant_bit_select"
non-terminal in "bind_target_instance" in the spec). If we turn out to
need this in future, we'll want to augment hierarchical_identifier and
its other users too.

Note that you can't easily use the BNF from the spec:

    bind_directive ::=
        "bind" bind_target_scope [ : bind_target_instance_list]
               bind_instantiation ;
      | "bind" bind_target_instance bind_instantiation ;

even if you fix the lookahead problem, because code like this matches
both branches in the BNF:

    bind a b b_i (.*);

The problem is that 'a' could either be a module name or a degenerate
hierarchical reference. This seems to be a genuine syntactic
ambiguity, which the spec resolves (p739) by saying that we have to
wait until resolution time (the hierarchy pass) and take whatever is
defined, treating 'a' as an instance name if it names both an instance
and a module.

To keep the parser simple, it currently accepts this invalid syntax:

    bind a.b : c d e (.*);

This is invalid because we're in the first branch of the BNF above, so
the "a.b" term should match bind_target_scope: a module or interface
identifier, not an arbitrary hierarchical identifier.

This will fail in the hierarchy pass (when it's implemented in a
future patch).
2021-07-16 09:31:39 -04:00
Zachary Snow a9c8ca21d5 sv: fix two struct access bugs
- preserve signedness of struct members
- fix initial width detection of struct members (e.g., in case expressions)
2021-07-15 11:57:20 -04:00
Claire Xen 55e8f5061a
Merge pull request #2817 from YosysHQ/claire/fixemails
Fixing old e-mail addresses and deadnames
2021-06-09 13:22:52 +02:00
Zachary Snow 2e697f5655 verilog: check for module scope identifiers during width detection
The recent fix for case expression width detection causes the width of
the expressions to be queried before they are simplified. Because the
logic supporting module scope identifiers only existed in simplify,
looking them up would fail during width detection. This moves the logic
to a common helper used in both simplify() and detectSignWidthWorker().
2021-06-08 15:03:16 -04:00
Claire Xenia Wolf 72787f52fc Fixing old e-mail addresses and deadnames
s/((Claire|Xen|Xenia|Clifford)\s+)+(Wolf|Xen)\s+<(claire|clifford)@(symbioticeda.com|clifford.at|yosyshq.com)>/Claire Xenia Wolf <claire@yosyshq.com>/gi;
s/((Nina|Nak|N\.)\s+)+Engelhardt\s+<nak@(symbioticeda.com|yosyshq.com)>/N. Engelhardt <nak@yosyshq.com>/gi;
s/((David)\s+)+Shah\s+<(dave|david)@(symbioticeda.com|yosyshq.com|ds0.me)>/David Shah <dave@ds0.me>/gi;
s/((Miodrag)\s+)+Milanovic\s+<(miodrag|micko)@(symbioticeda.com|yosyshq.com)>/Miodrag Milanovic <micko@yosyshq.com>/gi;
s,https?://www.clifford.at/yosys/,http://yosyshq.net/yosys/,g;
2021-06-08 00:39:36 +02:00
Zachary Snow 0795b3ec07 verilog: fix case expression sign and width handling
- The case expression and case item expressions are extended to the
  maximum width among them, and are only interpreted as signed if all of
  them are signed
- Add overall width and sign detection for AST_CASE
- Add sign argument to genWidthRTLIL helper
- Coverage for both const and non-const case statements
2021-05-25 16:16:46 -04:00
Rupert Swarbrick 3421979f00 Change the type of current_module to Module
The current_module global is needed so that genRTLIL has somewhere to
put cells and wires that it generates as it makes sense of expressions
that it sees. However, that doesn't actually need to be an AstModule:
the Module base class is enough.

This patch should cause no functional change, but the point is that
it's now possible to call genRTLIL with a module that isn't an
AstModule as "current_module". This will be needed for 'bind' support.
2021-05-13 23:44:48 -04:00
Marcelina Kościelnicka 89c74ffd71 verilog: Use proc memory writes in the frontend. 2021-03-08 20:16:29 +01:00
Marcelina Kościelnicka f4f471f342 frontend: Make helper functions for printing locations. 2021-02-23 23:51:52 +01:00
whitequark ad2960adb7
Merge pull request #2594 from zachjs/func-arg-width
verilog: fix sizing of constant args for tasks/functions
2021-02-23 21:46:16 +00:00
Zachary Snow b6af90fe20 verilog: fix sizing of constant args for tasks/functions
- Simplify synthetic localparams for normal calls to update their width
    - This step was inadvertently removed alongside `added_mod_children`
- Support redeclaration of constant function arguments
    - `eval_const_function` never correctly handled this, but the issue
      was not exposed in the existing tests until the recent change to
      always attempt constant function evaluation when all-const args
      are used
- Check asserts in const_arg_loop and const_func tests
- Add coverage for width mismatch error cases
2021-02-21 15:44:43 -05:00
Zachary Snow 8de2e863af verilog: support recursive functions using ternary expressions
This adds a mechanism for marking certain portions of elaboration as
occurring within unevaluated ternary branches. To enable elaboration of
the overall ternary, this also adds width detection for these
unelaborated function calls.
2021-02-12 14:43:42 -05:00
Zachary Snow b93b6f4285 verilog: refactored constant function evaluation
Elaboration now attempts constant evaluation of any function call with
only constant arguments, regardless of the context or contents of the
function. This removes the concept of "recommended constant evaluation"
which previously applied to functions with `for` loops or which were
(sometimes erroneously) identified as recursive. Any function call in a
constant context (e.g., `localparam`) or which contains a constant-only
procedural construct (`while` or `repeat`) in its body will fail as
before if constant evaluation does not succeed.
2021-02-04 10:18:27 -05:00
Zachary Snow fe74b0cd95 verilog: significant block scoping improvements
This change set contains a number of bug fixes and improvements related to
scoping and resolution in generate and procedural blocks. While many of the
frontend changes are interdependent, it may be possible bring the techmap
changes in under a separate PR.

Declarations within unnamed generate blocks previously encountered issues
because the data declarations were left un-prefixed, breaking proper scoping.
The LRM outlines behavior for generating names for unnamed generate blocks. The
original goal was to add this implicit labelling, but doing so exposed a number
of issues downstream. Additional testing highlighted other closely related scope
resolution issues, which have been fixed. This change also adds support for
block item declarations within unnamed blocks in SystemVerilog mode.

1. Unlabled generate blocks are now implicitly named according to the LRM in
   `label_genblks`, which is invoked at the beginning of module elaboration
2. The Verilog parser no longer wraps explicitly named generate blocks in a
   synthetic unnamed generate block to avoid creating extra hierarchy levels
   where they should not exist
3. The techmap phase now allows special control identifiers to be used outside
   of the topmost scope, which is necessary because such wires and cells often
   appear in unlabeled generate blocks, which now prefix the declarations within
4. Some techlibs required modifications because they relied on the previous
   invalid scope resolution behavior
5. `expand_genblock` has been simplified, now only expanding the outermost
   scope, completely deferring the inspection and elaboration of nested scopes;
   names are now resolved by looking in the innermost scope and stepping outward
6. Loop variables now always become localparams during unrolling, allowing them
   to be resolved and shadowed like any other identifier
7. Identifiers in synthetic function call scopes are now prefixed and resolved
   in largely the same manner as other blocks
     before: `$func$\func_01$tests/simple/scopes.blk.v:60$5$\blk\x`
      after: `\func_01$func$tests/simple/scopes.v:60$5.blk.x`
8. Support identifiers referencing a local generate scope nested more
   than 1 level deep, i.e. `B.C.x` while within generate scope `A`, or using a
   prefix of a current or parent scope, i.e. `B.C.D.x` while in `A.B`, `A.B.C`,
   or `A.B.C.D`
9. Variables can now be declared within unnamed blocks in SystemVerilog mode

Addresses the following issues: 656, 2423, 2493
2021-01-31 09:42:09 -05:00
Zachary Snow 2085d9a55d verilog: improved support for recursive functions 2020-12-31 18:33:59 -07:00
Udi Finkelstein b548722bee Added $high(), $low(), $left(), $right() 2020-09-15 20:49:52 +03:00
Zachary Snow c3e95eb1ab Fix generate scoping issues
- expand_genblock defers prefixing of items within named sub-blocks
- Allow partially-qualified references to local scopes
- Handle shadowing within generate blocks
- Resolve generate scope references within tasks and functions
- Apply generate scoping to genvars
- Resolves #2214, resolves #1456
2020-07-31 20:32:47 -06:00
Kazuki Sakamoto 185bbbe681 static cast: support changing size and signedness
Support SystemVerilog Static Cast
- size
- signedness
- (type is not supposted yet)

Fix #535
2020-06-19 17:39:20 -07:00
whitequark 7191dd16f9 Use C++11 final/override keywords. 2020-06-18 23:34:52 +00:00
Claire Wolf 7ad0c49905 Add latch detection for use_case_method in part-select write, fixes #2040
Signed-off-by: Claire Wolf <claire@symbioticeda.com>
2020-06-04 23:25:59 +02:00
Peter Crozier f482c9c016 Generalise structs and add support for packed unions. 2020-05-12 14:25:33 +01:00
Peter Crozier 0b6b47ca67 Implement SV structs. 2020-05-08 14:40:49 +01:00
Claire Wolf 589ed2d970 Add AST_SELFSZ and improve handling of bit slices
Signed-off-by: Claire Wolf <claire@symbioticeda.com>
2020-05-02 11:21:01 +02:00
Claire Wolf bbbce0d1c5 Add "nowrshmsk" attribute, fix shift-and-mask bit slice write for signed offset, fixes #1990
Signed-off-by: Claire Wolf <claire@symbioticeda.com>
2020-05-02 11:21:01 +02:00
Claire Wolf e1fb12a4b9 Add LookaheadRewriter for proper bitselwrite support
Signed-off-by: Claire Wolf <claire@symbioticeda.com>
2020-04-16 12:11:07 +02:00
Eddie Hung 4555b5b819 kernel: more pass by const ref, more speedups 2020-03-18 11:21:53 -07:00
Claire Wolf b597f85b13
Merge pull request #1718 from boqwxp/precise_locations
Closes #1717. Add more precise Verilog source location information to AST and RTLIL nodes.
2020-03-03 08:38:32 -08:00
Eddie Hung e79376d6cb ast: quiet down when deriving blackbox modules 2020-02-27 10:17:29 -08:00
Alberto Gonzalez f0afd65035
Closes #1717. Add more precise Verilog source location information to AST and RTLIL nodes. 2020-02-23 07:22:26 +00:00
Claire Wolf cd044a2bb6
Merge pull request #1642 from jjj11x/jjj11x/sv-enum
Enum support
2020-02-20 18:17:25 +01:00
David Shah 22c967e35e ast: Add support for $sformatf system function
Signed-off-by: David Shah <dave@ds0.me>
2020-01-19 21:20:17 +00:00
Jeff Wang 16ea4ea61a partial rebase of PeterCrozier's enum work onto current master
I tried to keep only the enum-related changes, and minimize the diff. (The
original commit also had a lot of work done to get typedefs working, but yosys
has diverged quite a bit since the 2018-03-09 commit, with a new typedef
implementation.) I did not include the import related changes either.

Original commit:
"Initial implementation of enum, typedef, import.  Still a WIP."
881833aa73
2020-01-16 13:51:47 -05:00
Clifford Wolf e84cedfae4 Use "(id)" instead of "id" for types as temporary hack
Signed-off-by: Clifford Wolf <clifford@clifford.at>
2019-10-14 05:24:31 +02:00
David Shah f6b5e47e40 sv: Switch parser to glr, prep for typedef
Signed-off-by: David Shah <dave@ds0.me>
2019-10-03 09:54:14 +01:00
Eddie Hung 08b55a20e3 module->derive() to be lazy and not touch ast if already derived 2019-09-30 14:11:01 -07:00
Clifford Wolf 8da0888bf6 Fix handling of read_verilog config in AstModule::reprocess_module(), fixes #1360
Signed-off-by: Clifford Wolf <clifford@clifford.at>
2019-09-20 12:16:20 +02:00
Clifford Wolf ec4565009a Add "read_verilog -pwires" feature, closes #1106
Signed-off-by: Clifford Wolf <clifford@clifford.at>
2019-06-19 14:38:50 +02:00
Clifford Wolf 211d85cfcc Fixes and cleanups in AST_TECALL handling
Signed-off-by: Clifford Wolf <clifford@clifford.at>
2019-06-07 12:41:09 +02:00
Clifford Wolf a3bbc5365b Merge branch 'pr_elab_sys_tasks' of https://github.com/udif/yosys into clifford/pr983 2019-06-07 12:08:42 +02:00
Stefan Biereigel 816082d5a1
Merge branch 'master' into wandwor 2019-05-27 19:07:46 +02:00
Stefan Biereigel cd12f2ddcf remove leftovers from ast data structures 2019-05-27 18:01:44 +02:00
Miodrag Milanovic 34417ce55f Added support for unsized constants, fixes #1022
Includes work from @sumit0190 and @AaronKel
2019-05-27 11:42:10 +02:00
Stefan Biereigel fd003e0e97 fix indentation across files 2019-05-23 13:57:27 +02:00
Stefan Biereigel 075a48d3fa implementation for assignments working 2019-05-23 13:57:27 +02:00
Stefan Biereigel 9df04d7e75 make lexer/parser aware of wand/wor net types 2019-05-23 13:57:27 +02:00
Udi Finkelstein ac10e7d96d Initial implementation of elaboration system tasks
(IEEE1800-2017 section 20.11)
This PR allows us to use $info/$warning/$error/$fatal **at elaboration time** within a generate block.
This is very useful to stop a synthesis of a parametrized block when an
illegal combination of parameters is chosen.
2019-05-03 03:10:43 +03:00
Clifford Wolf fb7f02be55 New behavior for front-end handling of whiteboxes
Signed-off-by: Clifford Wolf <clifford@clifford.at>
2019-04-20 22:24:50 +02:00
Clifford Wolf f4abc21d8a Add "whitebox" attribute, add "read_verilog -wb"
Signed-off-by: Clifford Wolf <clifford@clifford.at>
2019-04-18 17:45:47 +02:00