This will be necessary to implement EmitStreamVertex().
EmitVertex() will produce an ir_emit_vertex with the default stream 0.
Reviewed-by: Chris Forbes <chrisf@ijw.co.nz>
This patch replaces the ir_loop fields "from", "to", "increment",
"counter", and "cmp" with a single integer ("normative_bound") that
serves the same purpose.
I've used the name "normative_bound" to emphasize the fact that the
back-end is required to emit code to prevent the loop from running
more than normative_bound times. (By contrast, an "informative" bound
would be a bound that is informational only).
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
The compiler back-ends (i965's fs_visitor and brw_visitor,
ir_to_mesa_visitor, and glsl_to_tgsi_visitor) assume that when
ir_loop::counter is non-null, it points to a fresh ir_variable that
should be used as the loop counter (as opposed to an ir_variable that
exists elsewhere in the instruction stream).
However, previous to this patch:
(1) loop_control_visitor did not create a new variable for
ir_loop::counter; instead it re-used the existing ir_variable.
This caused the loop counter to be double-incremented (once
explicitly by the body of the loop, and once implicitly by
ir_loop::increment).
(2) ir_clone did not clone ir_loop::counter properly, resulting in the
cloned ir_loop pointing to the source ir_loop's counter.
(3) ir_hierarchical_visitor did not visit ir_loop::counter, resulting
in the ir_variable being missed by reparenting.
Additionally, most optimization passes (e.g. loop unrolling) assume
that the variable mentioned by ir_loop::counter is not accessed in the
body of the loop (an assumption which (1) violates).
The combination of these factors caused a perfect storm in which the
code worked properly nearly all of the time: for loops that got
unrolled, (1) would introduce a double-increment, but loop unrolling
would fail to notice it (since it assumes that ir_loop::counter is not
accessed in the body of the loop), so it would unroll the loop the
correct number of times. For loops that didn't get unrolled, (1)
would introduce a double-increment, but then later when the IR was
cloned for linking, (2) would prevent the loop counter from being
cloned properly, so it would look to further analysis stages like an
independent variable (and hence the double-increment would stop
occurring). At the end of linking, (3) would prevent the loop counter
from being reparented, so it would still belong to the shader object
rather than the linked program object. Provided that the client
program didn't delete the shader object, the memory would never get
reclaimed, and so the shader would function properly.
However, for loops that didn't get unrolled, if the client program did
delete the shader object, and the memory belonging to the loop counter
got re-used, this could cause a use-after-free bug, leading to a
crash.
This patch fixes loop_control_visitor, ir_clone, and
ir_hierarchical_visitor to treat ir_loop::counter the same way the
back-ends treat it: as a freshly allocated ir_variable that needs to
be visited and cloned independently of other ir_variables.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=72026
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
ARB_gpu_shader5 introduces new variants of textureGather* which have an
explicit component selector, rather than relying purely on the sampler's
swizzle state.
This patch adds the GLSL plumbing for the extra parameter.
Signed-off-by: Chris Forbes <chrisf@ijw.co.nz>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
These correspond to the EmitVertex and EndPrimitive functions in GLSL.
v2 (Paul Berry <stereotype441@gmail.com>): Add stub implementations of
new pure visitor functions to i965's vec4_visitor and fs_visitor
classes.
v3 (Paul Berry <stereotype441@gmail.com>): Rename classes to be more
consistent with the names used in the GL spec.
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
v2 [mattst88]:
- Rebase.
- #define GL_ARB_texture_query_lod to 1.
- Remove comma after ir_lod in ir.h for MSVC.
- Handled ir_lod in ir_hv_accept.cpp, ir_rvalue_visitor.cpp,
opt_tree_grafting.cpp.
- Rename textureQueryLOD to textureQueryLod, see
https://www.khronos.org/bugzilla/show_bug.cgi?id=821
- Fix ir_reader of (lod ...).
v3 [mattst88]:
- Rename textureQueryLod to textureQueryLOD, pending resolution of
Khronos 821.
- Add ir_lod case to ir_to_mesa.cpp.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
V2: - emit `sample` parameter properly for multisample texelFetch()
- fix spurious whitespace change
- introduce a new opcode ir_txf_ms rather than overloading the
existing ir_txf further. This makes doing the right thing in
the driver somewhat simpler.
V3: - fix weird whitespace
V4: - don't forget to include the new opcode in tex_opcode_strs[]
(thanks Kenneth for spotting this)
Signed-off-by: Chris Forbes <chrisf@ijw.co.nz>
[V2] Reviewed-by: Eric Anholt <eric@anholt.net>
[V2] Reviewed-by: Paul Berry <stereotype441@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Aside from ir_call, our IR is cleanly split into two classes:
- Statements (typeless; used for side effects, control flow)
- Values (deeply nestable, pure, typed expression trees)
Unfortunately, ir_call confused all this:
- For void functions, we placed ir_call directly in the instruction
stream, treating it as an untyped statement. Yet, it was a subclass
of ir_rvalue, and no other ir_rvalue could be used in this way.
- For functions with a return value, ir_call could be placed in
arbitrary expression trees. While this fit naturally with the source
language, it meant that expressions might not be pure, making it
difficult to transform and optimize them. To combat this, we always
emitted ir_call directly in the RHS of an ir_assignment, only using
a temporary variable in expression trees. Many passes relied on this
assumption; the acos and atan built-ins violated it.
This patch makes ir_call a statement (ir_instruction) rather than a
value (ir_rvalue). Non-void calls now take a ir_dereference of a
variable, and store the return value there---effectively a call and
assignment rolled into one. They cannot be embedded in expressions.
All expression trees are now pure, without exception.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Currently, ir_call can be used as either a statement (for void
functions) or a value (for non-void functions). This is rather awkward,
as it's the only class that can be used in both forms.
A number of places use ir_call::get_error_instruction() to construct a
generic value of error_type. If ir_call is to become a statement, it
can no longer serve this purpose.
Unfortunately, none of our classes are particularly well suited for
this, and creating a new one would be rather aggrandizing. So, this
patch introduces ir_rvalue::error_value(), a static method that creates
an instance of the base class, ir_rvalue. This has the nice property
that you can't accidentally try and access uninitialized fields (as it
doesn't have any). The downside is that the base class is no longer
abstract.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
This patch fixes a bug in ir_hirearchical_visitor: when traversing an
exec_list representing the formal or actual parameters of a function,
it modified base_ir to point to each parameter in turn, rather than
leaving it as a pointer to the enclosing statement. This was a
problem, since base_ir is used by visitor classes to locate the
statement containing the node being visited (usually so that
additional statements can be inserted before or after it). Without
this fix, visitors might attempt to insert statements into parameter
lists.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
One unique aspect of TXS is that it doesn't have a coordinate.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Having these as actual integer values makes it difficult to implement
the texture*Offset built-in functions, since the offset is actually a
function parameter (which doesn't have a constant value).
The original rationale was that some hardware needs these offset baked
into the instruction opcode. However, at least i965 should be able to
support non-constant offsets. Others should be able to rely on inlining
and constant propagation.
It now works correctly when nodes are removed, as it was originally
intended to do; it no longer processes nodes added to the list before
the current node, nor those added immediately after the current node.
This matches the behavior of Linux's list_for_each_safe.
