Commit graph

236 commits

Author SHA1 Message Date
Eric Anholt
f7561e8ecd glsl: Turn UBO variable declarations into ir_variables and check qualifiers.
Fixes piglit layout-*-non-uniform and layout-*-within-block.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2012-07-20 10:43:12 -07:00
Kenneth Graunke
d43f4181e1 glsl: Remove open coded version of ir_variable::interpolation_string().
Presumably the function didn't exist when we wrote this code.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2012-07-19 11:00:00 -07:00
Eric Anholt
2d03f48a65 glsl: Add parsing for GLSL uniform blocks.
This doesn't do anything with the uniform block declarations yet, so
usage of those uniforms finds them to be undeclared.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2012-07-09 11:13:33 -07:00
Ian Romanick
adfe531841 glsl: Remove spurious printf messages
These look like debug messages from the switch-statement development.

NOTE: This is a candidate for the 8.0 release branch.

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
2012-06-01 12:27:04 -07:00
Eric Anholt
aa5ec13775 glsl: Drop the extra NULL specifiction on ir_assignment constructors.
It's an implied argument, and I don't think being explicit about it
helps.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2012-05-17 10:05:24 -07:00
Eric Anholt
9c4e9ce051 glsl: Fix assertion failure on handling switch on uint expressions.
Fixes piglit glsl-1.30/execution/switch/fs-uint.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2012-05-17 10:05:24 -07:00
Eric Anholt
bbbc7c7d56 glsl: Reject non-scalar switch expressions.
The comment quotes spec saying that only scalar integers are allowed,
but we only checked for integer.

Fixes piglit switch-expression-const-ivec2.vert

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2012-05-17 10:05:24 -07:00
Eric Anholt
5d6ea16dfe glsl: Let the constructor figure out the types of switch-related expressions.
I noticed this while unindenting the code.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2012-05-17 10:05:24 -07:00
Eric Anholt
5462f3679a glsl: Fix indentation of switch code.
I managed to completely trash it in 22d81f15.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2012-05-17 10:05:23 -07:00
Eric Anholt
b2ee5a08ba glsl: Don't consider unused FS out variables as being statically assigned.
I only considered var->assigned for FragColor and FragData, but
ignored when it was false for out vars.  Fixes piglit
write-gl_FragColor-and-not-user-output.frag

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=49068
2012-05-04 14:00:32 -07:00
Eric Anholt
4b2a4cb7c2 glsl: Properly throw compile-time errors for conflicting FS output writes.
We were checking for these at link time previously, which is not as
early as mandated, and would actually fail to detect conflicting
writes if dead code removal removed some writes.

Fixes failures in piglit
glsl-*/compiler/fragment-outputs/write-gl_Frag*

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
2012-04-19 16:33:45 -07:00
Eric Anholt
f2475ca424 glsl: Track in each ir_variable whether it was ever assigned.
This will be used for some compile-and-link-time error checking, where
currently we've been doing error checking only at link time.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
2012-04-19 16:33:36 -07:00
Dave Airlie
1256a5dcc8 glsl: add support for ARB_blend_func_extended (v3)
This adds index support to the GLSL compiler.

I'm not 100% sure of my approach here, esp without how output ordering
happens wrt location, index pairs, in the "mark" function.

Since current hw doesn't ever have a location > 0 with an index > 0,
we don't have to work out if the output ordering the hw requires is
location, index, location, index or location, location, index, index.
But we have no hw to know, so punt on it for now.

v2: index requires layout - catch and error
    setup explicit index properly.

v3: drop idx_offset stuff, assume index follow location

Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-04-13 17:19:01 +01:00
Eric Anholt
eb7a71dea7 glsl: Drop the round-trip through ast_type_specifier for many builtin types.
We have lexer recognition of a bunch of our types based on the
handling.  This code was mapping those recognized tokens to an enum
and then to a string of their name.  Just drop the enums and provide
the string directly in the parser.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
2012-04-09 14:30:46 -07:00
Kenneth Graunke
807e967c61 glsl: Use ir_rvalue to represent generic error_type values.
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>
2012-04-02 14:15:34 -07:00
Kenneth Graunke
dca19a7711 glsl: Explicitly NULL-check variables before making a dereference.
The constructor currently returns a ir_dereference_variable of error
type when provided NULL, but that's about to change in the next commit.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
2012-03-26 10:21:55 -07:00
Eric Anholt
ead3589aa2 glsl: Avoid extra if statements for logic and/or with no side effects.
This avoids extra if statements in the common case of just comparing
two expressions that don't involve assignments or function calls,
along with simplifying the handling of constant expressions.  Reduces
i965 instructions generated in unigine tropics and sanctuary,
yofrankie, warsow, gstreamer shaders, and the weston compositor.

shader-db results:
Total instructions: 213052 -> 212752
38/1246 programs affected (3.0%)
14309 -> 14009 instructions in affected programs (2.1% reduction)
2012-03-13 13:50:08 -07:00
Eric Anholt
57e44371a5 glsl: Add error case for switch() with two default cases.
Fixes piglit switch-case-duplicated.vert.

NOTE: This is a candidate for the 8.0 branch.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2012-02-03 11:07:04 +01:00
Eric Anholt
140632190c glsl: Throw an error when faced with a duplicated switch() case label.
The error message I chose matches gcc's error.  Fixes piglit
switch-case-duplicated.vert.

NOTE: This is a candidate for the 8.0 branch.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2012-02-03 11:07:02 +01:00
Eric Anholt
2c3e10e719 glsl: Throw the required error when a case label is a non-constant.
It's not quite spelled out in the spec text, but the grammar indicates
that only constant values are allowed as switch() case labels (and
only constant values make sense, anyway).

Fixes piglit glsl-1.30/compiler/switch-statement/switch-case-uniform-int.vert.

NOTE: This is a candidate for the 8.0 branch.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2012-02-03 11:06:54 +01:00
Eric Anholt
22d81f154f glsl: Save and restore the whole switch state for nesting.
This stuffs them all in a struct for sanity.  Fixes piglit
glsl-1.30/execution/switch/fs-uniform-nested.

NOTE: This is a candidate for the 8.0 branch.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2012-02-03 11:06:50 +01:00
Eric Anholt
916e206ef0 glsl: Add error checking for applying interpolation qualifiers to other vars.
Fixes piglit
glsl-1.30/compiler/interpolation-qualifiers/local-smooth-01.frag.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
2012-01-10 16:44:16 -08:00
Ian Romanick
1f125374e7 glsl: Don't mark assignment temporaries as read-only
The various l-value errors this was designed to catch are now caught
by other means.  Marking the temporaries as read-only now just
prevents sensible error messages from being generated.  It's

0:0(0): error: function parameter 'out p' references the read-only variable '_post_incdec_tmp'

versus

0:13(5): error: function parameter 'out p' references a post-decrement operation

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Paul Berry <stereotype441@gmail.com>
2012-01-06 14:32:50 -08:00
Ian Romanick
e9015e99d0 glsl: Emit errors for assignments to non-l-value expressions
Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Paul Berry <stereotype441@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=42755
2012-01-06 14:32:50 -08:00
Ian Romanick
fa0a9ac5cd glsl: Track descriptions of some expressions that can't be l-values
Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Paul Berry <stereotype441@gmail.com>
2012-01-06 14:32:50 -08:00
Ian Romanick
3946448951 glsl: Don't use base type for bit-not when there's an error
Other parts of the compiler assume that expressions will have
well-formed types or the error type.  Just using the type of the thing
being operated on can cause expressions like ~3.14 or ~false to not
have a well-formed type.  This could then result in an assertion
failure in the context epxression handler.

If there is an error processing the expression, set the type of the IR
expression to error.

Fixes piglit's bit-not-0[789].frag tests.

NOTE: This is a candidate for the 7.11 branch.

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=42755
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Cc: Vinson Lee <vlee@vmware.com>
2012-01-04 12:43:10 -08:00
Marek Olšák
6b43d6fdda glsl: finish up ARB_conservative_depth (v2)
v2: updated an error message

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2011-11-22 20:56:50 +01:00
Dan McCabe
5c02e2e2de glsl: Generate IR for switch statements
Up until now modifying the GLSL compiler has been pretty straightforward.
This is where things get interesting. But still pretty straightforward.

Switch statements can be thought of a series of if/then/else statements.
Case labels are compared with the value of a test expression and the case
statements are executed if the comparison is true.

There are a couple of aspects of switch statements that complicate this simple
view of the world. The primary one is that cases can fall through sequentially
to subsequent case, unless a break statement is encountered, in which case,
the switch statement exits completely.

But break handling is further complicated by the fact that a break statement
can impact the exit of a loop. Thus, we need to coordinate break processing
between switch statements and loop statements.

The code generated by a switch statement maintains three temporary state
variables:
    int test_value;
    bool is_fallthru;
    bool is_break;

test_value is initialized to the value of the test expression at the head of
the switch statement. This is the value that case labels are compared against.

is_fallthru is used to sequentially fall through to subsequent cases and is
initialized to false. When a case label matches the test expression, this
state variable is set to true. It will also be forced to false if a break
statement has been encountered. This forcing to false on break MUST be
after every case test. In practice, we defer that forcing to immediately after
the last case comparison prior to executing a case statement, but that is
an optimization.

is_break is used to indicate that a break statement has been executed and is
initialized to false. When a break statement is encountered, it is set to true.
This state variable is then used to conditionally force is_fallthru to to false
to prevent subsequent case statements from executing.

Code generation for break statements depends on whether the break statement is
inside a switch statement or inside a loop statement. If it inside a loop
statement is inside a break statement, the same code as before gets generated.
But if a switch statement is inside a loop statement, code is emitted to set
the is_break state to true.

Just as ASTs for loop statements are managed in a stack-like
manner to handle nesting, we also add a bool to capture the innermost switch
or loop condition. Note that we still need to maintain a loop AST stack to
properly handle for-loop code generation on a continue statement. Technically,
we don't (yet) need a switch AST stack, but I am using one for orthogonality
with loop statements, in anticipation of future use. Note that a simple
boolean stack would have sufficed.

We will illustrate a switch statement with its analogous conditional code that
a switch statement corresponds to by examining an example.

Consider the following switch statement:
	switch (42) {
	case 0:
	case 1:
		gl_FragColor = vec4(1.0, 2.0, 3.0, 4.0);
	case 2:
	case 3:
		gl_FragColor = vec4(4.0, 3.0, 2.0, 1.0);
		break;
	case 4:
	default:
		gl_FragColor = vec4(0.0, 0.0, 0.0, 0.0);
	}

Note that case 0 and case 1 fall through to cases 2 and 3 if they occur.

Note that case 4 and the default case must be reached explicitly, since cases
2 and 3 break at the end of their case.

Finally, note that case 4 and the default case don't break but simply fall
through to the end of the switch.

For this code, the equivalent code can be expressed as:
	int test_val = 42; // capture value of test expression
	bool is_fallthru = false; // prevent initial fall through
	bool is_break = false; // capture the execution of a break stmt

	is_fallthru |= (test_val == 0); // enable fallthru on case 0
	is_fallthru |= (test_val == 1); // enable fallthru on case 1
	is_fallthru &= !is_break; // inhibit fallthru on previous break
	if (is_fallthru) {
		gl_FragColor = vec4(1.0, 2.0, 3.0, 4.0);
	}

	is_fallthru |= (test_val == 2); // enable fallthru on case 2
	is_fallthru |= (test_val == 3); // enable fallthru on case 3
	is_fallthru &= !is_break; // inhibit fallthru on previous break
	if (is_fallthru) {
		gl_FragColor = vec4(4.0, 3.0, 2.0, 1.0);
		is_break = true; // inhibit all subsequent fallthru for break
	}

	is_fallthru |= (test_val == 4); // enable fallthru on case 4
	is_fallthru = true; // enable fallthru for default case
	is_fallthru &= !is_break; // inhibit fallthru on previous break
	if (is_fallthru) {
		gl_FragColor = vec4(0.0, 0.0, 0.0, 0.0);
	}

The code generate for |= and &= uses the conditional assignment capabilities
of the IR.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
2011-11-07 16:31:22 -08:00
Dan McCabe
85beb39e14 glsl: Reference data structure ctors in grammar
We now tie the grammar to the ctors of the ASTs they reference.

This requires that we actually have definitions of the ctors.

In addition, we also need to define "print" and "hir" methods for the AST
classes. The Print methods are pretty simple to flesh out. However, at this
stage of the development, we simply stub out the "hir" methods and flesh
them out later.

Also, since actual class instances get returned by the productions in the
grammar, we also need to designate the type of the productions that
reference those instances.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
2011-11-07 16:31:22 -08:00
Ian Romanick
f37b1ad937 linker: Check that initializers for global variables match
This requires tracking a couple extra fields in ir_variable:

 * A flag to indicate that a variable had an initializer.

 * For non-const variables, a field to track the constant value of the
   variable's initializer.

For variables non-constant initalizers, ir_variable::has_initializer
will be true, but ir_variable::constant_initializer will be NULL.  The
linker can use the values of these fields to check adherence to the
GLSL 4.20 rules for shared global variables:

    "If a shared global has multiple initializers, the initializers
    must all be constant expressions, and they must all have the same
    value. Otherwise, a link error will result. (A shared global
    having only one initializer does not require that initializer to
    be a constant expression.)"

Previous to 4.20 the GLSL spec simply said that initializers must have
the same value.  In this case of non-constant initializers, this was
impossible to determine.  As a result, no vendor actually implemented
that behavior.  The 4.20 behavior matches the behavior of NVIDIA's
shipping implementations.

NOTE: This is candidate for the 7.11 branch.  This patch also needs
the preceding patch "glsl: Refactor generate_ARB_draw_buffers_variables
to use add_builtin_constant"

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=34687
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Acked-by: Paul Berry <stereotype441@gmail.com>
2011-11-03 13:36:00 -07:00
Paul Berry
9abda92b27 glsl: Fix type mismatch when incrementing or decrementing uint.
When converting an expression like "++x" to GLSL IR we were failing to
account for the possibility that x might be an unsigned integral type.
As a result the user would receive a bogus error message "Could not
implicitly convert operands to arithmetic operator".

Fixes piglit tests {vs,fs}-{increment,decrement}-uint.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
2011-11-02 09:28:54 -07:00
Ian Romanick
f5ba4d055e glsl: Clean-up spurious error message on bad structure definitions
Previously a shader like

int X;
struct X { int i; };

void main() { gl_Position = vec4(0.0); }

would generate two error message:

0:2(19): error: struct `X' previously defined
0:2(20): error: incomplete declaration

The first one is the real error, and the second is spurious.

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
2011-10-28 13:28:55 -07:00
Ian Romanick
a04211ecb8 glsl: Generate an error for array-of-array declarations
Other parts of the code already caught things like 'float x[4][2]'.
However, nothing caught 'float [4] x[2]'.

Fixes piglit test array-multidimensional-new-syntax.vert.

NOTE: This is candidate for the 7.11 branch.

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
2011-10-28 13:28:36 -07:00
Paul Berry
c488150dea glsl: Distinguish between no interpolation qualifier and 'smooth'
Previously, we treated the 'smooth' qualifier as equivalent to no
qualifier at all.  However, this is incorrect for the built-in color
variables (gl_FrontColor, gl_BackColor, gl_FrontSecondaryColor, and
gl_BackSecondaryColor).  For those variables, if there is no qualifier
at all, interpolation should be flat if the shade model is GL_FLAT,
and smooth if the shade model is GL_SMOOTH.

To make this possible, I added a new value to the
glsl_interp_qualifier enum, INTERP_QUALIFIER_NONE.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
2011-10-27 15:31:20 -07:00
Paul Berry
cf45949d6a mesa: Expose GLSL interpolation qualifiers in gl_fragment_program.
This patch makes GLSL interpolation qualifiers visible to drivers via
the array InterpQualifier[] in gl_fragment_program, so that they can
easily be used by driver back-ends to select the correct interpolation
mode.

Previous to this patch, the GLSL compiler was using the enum
ir_variable_interpolation to represent interpolation types.  Rather
than make a duplicate enum in core mesa to represent the same thing, I
moved the enum into mtypes.h and renamed it to be more consistent with
the other enums defined there.

Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
2011-10-27 15:30:58 -07:00
Jason Wood
c475a54578 glsl: Remove version check when looking for identifiers containing "__".
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
2011-10-06 22:39:08 -07:00
Eric Anholt
684b701c12 glsl: Consider "__" in identifers as reserved.
Fixes double-underscore-*.frag.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
2011-10-05 12:49:17 -07:00
Kenneth Graunke
0fabf8e8dc glsl: Defer initialization of built-in functions until they're needed.
Very simple shaders don't actually use GLSL built-ins.  For example:
- gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;
- gl_FragColor = vec4(0.0);
Both of the shaders used by _mesa_meta_glsl_Clear() also qualify.

By waiting to initialize the built-ins until the first time we need to
look for a signature, we can avoid the overhead entirely in these cases.

Makes piglit run roughly 18% faster (255 vs. 312 seconds).

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
2011-09-23 17:12:47 -07:00
Paul Berry
00792e3586 glsl: Remove field array_lvalue from ir_variable.
The array_lvalue field was attempting to enforce the restriction that
whole arrays can't be used on the left-hand side of an assignment in
GLSL 1.10 or GLSL ES, and can't be used as out or inout parameters in
GLSL 1.10.

However, it was buggy (it didn't work properly for built-in arrays),
and it was clumsy (it unnecessarily kept track on a
variable-by-variable basis, and it didn't cover the GLSL ES case).

This patch removes the array_lvalue field completely in favor of
explicit checks in ast_parameter_declarator::hir() (this check is
added) and in do_assignment (this check was already present).

This causes a benign behavioral change: when the user attempts to pass
an array as an out or inout parameter of a function in GLSL 1.10, the
error is now flagged at the time the function definition is
encountered, rather than at the time of invocation.  Previously we
allowed such functions to be defined, and only flagged the error if
they were invoked.

Fixes Piglit tests
spec/glsl-1.10/compiler/qualifiers/fn-{out,inout}-array-prohibited*
and
spec/glsl-1.20/compiler/assignment-operators/assign-builtin-array-allowed.vert.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
2011-09-14 10:58:56 -07:00
Ian Romanick
9a3bd5e045 glsl: Silence several "warning: unused parameter" 2011-09-09 12:01:50 -07:00
Eric Anholt
525cec98a5 glsl: Clarify error message about whole-array assignment in GLSL 1.10.
Previously, it would produce:

    Failed to compile FS: 0:6(7): error: non-lvalue in assignment

and now it produces:

    Failed to compile FS: 0:5(7): error: whole array assignment is not
    allowed in GLSL 1.10 or GLSL ES 1.00.

Also, add spec quotation to the two places we have code for array
lvalues in GLSL 1.10.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2011-09-08 20:20:49 -07:00
Eric Anholt
407a1001ae glsl: When assiging from a whole array, mark it as used.
Fixes piglit link-uniform-array-size.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2011-09-08 20:20:49 -07:00
Paul Berry
37bb1c4de2 glsl: Check that gl_ClipDistance[] is not sized too large.
Fixes piglit tests
clip-distance-explicit-too-large-with-access.{frag,vert} and
clip-distance-explicit-too-large.{frag,vert}.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2011-09-08 09:37:45 -07:00
Paul Berry
93b9758d01 glsl: Rework oversize array check for gl_TexCoord.
The check now applies both when explicitly declaring the size of
gl_TexCoord and when implicitly setting the size of gl_TexCoord by
accessing it using integral constant expressions.

This is prep work for adding similar size checks to gl_ClipDistance.

Fixes piglit tests texcoord/implicit-access-max.{frag,vert}.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2011-09-08 09:37:24 -07:00
Eric Anholt
a313c29c77 glsl: When assigning to a whole array, mark the array as accessed.
The vs-varying-array-mat2-col-row-wr test writes a mat2[3] constant to
a mat2[3] varying out array, and also statically accesses element 1 of
it on the VS and FS sides.  At link time it would get trimmed down to
just 2 elements, and then codegen of the VS would end up generating
assignments to the unallocated last entry of the array.  On the new
i965 VS backend, that happened to land on the vertex position.

Some issues remain in this test on softpipe, i965/old-vs and
i965/new-vs on visual inspection, but i965 is passing because only one
green pixel is probed, not the whole split green/red quad.
2011-08-15 17:54:27 -07:00
Paul Berry
d4144a123b glsl: Check array size is const before asserting that no IR was generated.
process_array_type() contains an assertion to verify that no IR
instructions are generated while processing the expression that
specifies the size of the array.  This assertion needs to happen
_after_ checking whether the expression is constant.  Otherwise we may
crash on an illegal shader rather than reporting an error.

Fixes piglit tests array-size-non-builtin-function.vert and
array-size-with-side-effect.vert.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
2011-08-08 12:43:53 -07:00
Paul Berry
0d81b0e184 glsl: Emit function signatures at toplevel, even for built-ins.
The ast-to-hir conversion needs to emit function signatures in two
circumstances: when a function declaration (or definition) is
encountered, and when a built-in function is encountered.

To avoid emitting a function signature in an illegal place (such as
inside a function), emit_function() checked whether we were inside a
function definition, and if so, emitted the signature before the
function definition.

However, this didn't cover the case of emitting function signatures
for built-in functions when those built-in functions are called from
inside the constant integer expression that specifies the length of a
global array.  This failed because when processing an array length, we
are emitting IR into a dummy exec_list (see process_array_type() in
ast_to_hir.cpp).  process_array_type() later checks (via an assertion)
that no instructions were emitted to the dummy exec_list, based on the
reasonable assumption that we shouldn't need to emit instructions to
calculate the value of a constant.

This patch changes emit_function() so that it emits function
signatures at toplevel in all cases.

This partially fixes bug 38625
(https://bugs.freedesktop.org/show_bug.cgi?id=38625).  The remainder
of the fix is in the patch that follows.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
2011-08-08 12:43:38 -07:00
Chia-I Wu
547212d963 glsl: empty declarations should be valid
Unlike C++, empty declarations such as

  float;

should be valid.  The spec is not explicit about this actually.

Some apps that generate their shader sources may rely on this.  This was
noted when porting one of them to Linux from Windows.

Reviewed-by: Chad Versace <chad@chad-versace.us>

Note: this is a candidate for the 7.11 branch.
2011-08-05 12:14:24 +09:00
Ian Romanick
02c5ae1b3f glsl: Reject shaders that contain static recursion
The GLSL 1.20 and later specs say:

    "Recursion is not allowed, not even statically. Static recursion is
    present if the static function call graph of the program contains
    cycles."

Recursion is detected and rejected both a compile-time and at
link-time.  The complie-time check happens to detect some cases that
may be removed by various optimization passes.  The spec doesn't seem
to allow this, but other vendors (e.g., NVIDIA) appear to only check
at link-time after all optimizations.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=33885
Reviewed-by: Paul Berry <stereotype441@gmail.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
2011-07-20 18:20:59 -07:00
Paul Berry
f07221056e glsl: Ensure that sampler declarations are always uniform or "in" parameters.
This brings us into compliance with page 17 (page 22 of the PDF) of
the GLSL 1.20 spec:

    "[Sampler types] can only be declared as function parameters or
    uniform variables (see Section 4.3.5 "Uniform"). ... [Samplers]
    cannot be used as out or inout function parameters."

The spec isn't explicit about whether this rule applies to
structs/arrays containing shaders, but the intent seems to be to
ensure that it can always be determined at compile time which sampler
is being used in each texture lookup.  So to avoid creating a
loophole, the rule needs to apply to structs/arrays containing shaders
as well.

Fixes piglit tests spec/glsl-1.10/compiler/samplers/*.frag, and fixes
bug 38987.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=38987
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2011-07-18 10:48:27 -07:00