Commit graph

8 commits

Author SHA1 Message Date
Kenneth Graunke
3603fdcebf glsl: Hook up loop_variable_state destructor to plug a memory leak.
While ~loop_state() is already freeing the loop_variable_state objects
via ralloc_free(this->mem_ctx), the ~loop_variable_state() destructor
was never getting called, so the hash table inside loop_variable_state
was never getting destroyed.

Fixes a memory leak in any shader with loops.

NOTE: This is a candidate for stable release branches.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
2012-06-07 00:01:40 -07:00
Kenneth Graunke
0405bd08ca glsl: Don't trust loop analysis in the presence of function calls.
Function calls may have side effects that alter variables used inside
the loop.  In the fragment shader, they may even terminate the shader.
This means our analysis about loop-constant or induction variables may
be completely wrong.

In general it's impossible to determine whether they actually do or not
(due to the halting problem), so we'd need to perform conservative
static analysis.  For now, it's not worth the complexity: most functions
will be inlined, at which point we can unroll them successfully.

Fixes Piglit tests:
- shaders/glsl-fs-unroll-out-param
- shaders/glsl-fs-unroll-side-effect

NOTE: This is a candidate for release branches.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
2012-04-02 14:15:19 -07:00
Eric Anholt
58c988ada5 glsl: Skip the rest of loop unrolling if no loops were found.
Shaves 1.6% (+/- 1.0%) off of ff_fragment_shader glean texCombine time
(n=5).
2011-01-18 10:17:37 -08:00
Luca Barbieri
e591c4625c glsl: add several EmitNo* options, and MaxUnrollIterations
This increases the chance that GLSL programs will actually work.

Note that continues and returns are not yet lowered, so linking
will just fail if not supported.

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
2010-09-08 20:36:37 -07:00
Ian Romanick
de7c3fe31a glsl2: Add module to perform simple loop unrolling 2010-09-03 11:55:22 -07:00
Ian Romanick
3bcfafcf03 glsl2: Track the number of ir_loop_jump instructions that are in a loop 2010-09-03 11:55:22 -07:00
Ian Romanick
bfe3fbb38e glsl2: Add module to suss out loop control variables from loop analysis data
This is the next step on the road to loop unrolling
2010-09-03 11:55:21 -07:00
Ian Romanick
9434a0749f glsl2: Add module to analyze variables used in loops
This is the first step eventually leading to loop unrolling.
2010-09-03 11:55:21 -07:00