gallium: implement bounds checking for constant buffers

Plumb the constant buffer sizes down into the tgsi interpreter where
we can do bounds checking.  Optional debug code warns upon out-of-bounds
reading.  Plus add a few other assertions in the TGSI interpreter.

3 files changed, 7 insertions, 3 deletions

diff --git a/src/gallium/drivers/softpipe/sp_context.h b/src/gallium/drivers/softpipe/sp_context.h
index c5f53cfa61a..9361a3df09e 100644
--- a/src/gallium/drivers/softpipe/sp_context.h
+++ b/src/gallium/drivers/softpipe/sp_context.h
@@ -112,6 +112,7 @@ struct softpipe_context {
 
    /** Mapped constant buffers */
    const void *mapped_constants[PIPE_SHADER_TYPES][PIPE_MAX_CONSTANT_BUFFERS];
+   unsigned const_buffer_size[PIPE_SHADER_TYPES][PIPE_MAX_CONSTANT_BUFFERS];
 
    /** Vertex format */
    struct vertex_info vertex_info;
diff --git a/src/gallium/drivers/softpipe/sp_quad_fs.c b/src/gallium/drivers/softpipe/sp_quad_fs.c
index d240bcbf3bb..90f4787d599 100644
--- a/src/gallium/drivers/softpipe/sp_quad_fs.c
+++ b/src/gallium/drivers/softpipe/sp_quad_fs.c
@@ -111,9 +111,10 @@ shade_quads(struct quad_stage *qs,
    struct tgsi_exec_machine *machine = softpipe->fs_machine;
    unsigned i, nr_quads = 0;
 
-   for (i = 0; i < PIPE_MAX_CONSTANT_BUFFERS; i++) {
-      machine->Consts[i] = softpipe->mapped_constants[PIPE_SHADER_FRAGMENT][i];
-   }
+   tgsi_exec_set_constant_buffers(machine, PIPE_MAX_CONSTANT_BUFFERS,
+                         softpipe->mapped_constants[PIPE_SHADER_FRAGMENT],
+                         softpipe->const_buffer_size[PIPE_SHADER_FRAGMENT]);
+
    machine->InterpCoefs = quads[0]->coef;
 
    for (i = 0; i < nr; i++) {
diff --git a/src/gallium/drivers/softpipe/sp_state_fs.c b/src/gallium/drivers/softpipe/sp_state_fs.c
index 3fbf1f25781..ded242d3dc5 100644
--- a/src/gallium/drivers/softpipe/sp_state_fs.c
+++ b/src/gallium/drivers/softpipe/sp_state_fs.c
@@ -195,6 +195,8 @@ softpipe_set_constant_buffer(struct pipe_context *pipe,
    }
 
    softpipe->mapped_constants[shader][index] = data;
+   softpipe->const_buffer_size[shader][index] = size;
+
    softpipe->dirty |= SP_NEW_CONSTANTS;
 }