The $shift and $shiftx cells perform a left logical shift if the second
operand is negative. This change passes the sign of the second operand
of AST_SHIFT and AST_SHIFTX into $shift and $shiftx cells, respectively.
Compiling on GCC hid this bug as it optimized the nullptr call away as
undefined behavior, but running the SBY tests with a clang build hits
this error.
Instead of passing around in_lvalue/in_param flags to simplify, we make
the flags into properties of the AST nodes themselves. After the tree
is first parsed, we once do
ast->fixup_hierarchy_flags(true)
to walk the full hierarchy and set the flags to their initial correct
values. Then as long as one is using ->clone(), ->cloneInto() and the
AstNode constructor (with children passed to it) to modify the tree, the
flags will be kept in sync automatically. On the other hand if we are
modifying the children list of an existing node, we may need to call
node->fixup_hierarchy_flags()
to do a localized fixup. That fixup will update the flags on the node's
children, and will propagate the change down the tree if necessary.
clone() doesn't always retain the flags of the subtree being cloned. It
will produce a tree with a consistent setting of the flags, but the
root doesn't have in_param/in_lvalue set unless it's intrinsic to the
type of node being cloned (e.g. AST_PARAMETER). cloneInto() will make
sure the cloned subtree has the flags consistent with the new placement
in a hierarchy.
Add asserts to make sure the old and new way of determining the flags
agree.
The following commit will replace the way in_lvalue/in_param is being
tracked in the simplify code. Make tweaks in advance so that it will
be easier to make the old way and the new way agree.
These changes all should be innocuous.
- Add support for assignments within expressions, e.g., `x[y++] = z;` or
`x = (y *= 2) - 1;`. The logic is handled entirely within the parser
by injecting statements into the current procedural block.
- Add support for pre-increment/decrement statements, which are
behaviorally equivalent to post-increment/decrement statements.
- Fix non-standard attribute position used for post-increment/decrement
statements.
The correct way of using the 'at_zero' regime of simplify is to perform
the simplification on a cloned AST subtree, otherwise the "at_zero"
evaluation seeps into the main tree.
Move the effect of the 'at_zero' flag to the cloning itself, so that
the simplify flag can be retired. We assume we can rely on id2ast in
the new clone method.
It's a repeating pattern to print an error message tied to an AST
node. Start using an 'input_error' helper for that. Among other
things this is beneficial in shortening the print lines, which tend
to be long.
Martin Povišer
Dag Lem
Miodrag Milanovic
N. Engelhardt
Jannis Harder
Zachary Snow
Charlotte
whitequark