Mesa (master): mesa: use check_resources() to check program against limits

[Brian Paul]

Module: Mesa
Branch: master
Commit: 8cc84b3e454cf03c71282322e988f03bc4a1baa3
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=8cc84b3e454cf03c71282322e988f03bc4a1baa3

Author: Brian Paul <brianp at vmware.com>
Date:   Fri Mar 11 09:25:22 2011 -0700

mesa: use check_resources() to check program against limits

Without these checks we could create shaders with more samplers,
constants than the driver could handle.  Fail linking rather than
dying later.

---

 src/mesa/program/ir_to_mesa.cpp |   58 +++++++++++++++++++++++++++++++++++++++
 1 files changed, 58 insertions(+), 0 deletions(-)

diff --git a/src/mesa/program/ir_to_mesa.cpp b/src/mesa/program/ir_to_mesa.cpp
index 33c262f..9c77f38 100644
--- a/src/mesa/program/ir_to_mesa.cpp
+++ b/src/mesa/program/ir_to_mesa.cpp
@@ -2406,6 +2406,11 @@ print_program(struct prog_instruction *mesa_instructions,
    }
 }
 
+
+/**
+ * Count resources used by the given gpu program (number of texture
+ * samplers, etc).
+ */
 static void
 count_resources(struct gl_program *prog)
 {
@@ -2429,6 +2434,57 @@ count_resources(struct gl_program *prog)
    _mesa_update_shader_textures_used(prog);
 }
 
+
+/**
+ * Check if the given vertex/fragment/shader program is within the
+ * resource limits of the context (number of texture units, etc).
+ * If any of those checks fail, record a linker error.
+ *
+ * XXX more checks are needed...
+ */
+static void
+check_resources(const struct gl_context *ctx,
+                struct gl_shader_program *shader_program,
+                struct gl_program *prog)
+{
+   switch (prog->Target) {
+   case GL_VERTEX_PROGRAM_ARB:
+      if (_mesa_bitcount(prog->SamplersUsed) >
+          ctx->Const.MaxVertexTextureImageUnits) {
+         fail_link(shader_program, "Too many vertex shader texture samplers");
+      }
+      if (prog->Parameters->NumParameters >
+          ctx->Const.VertexProgram.MaxParameters) {
+         fail_link(shader_program, "Too many vertex shader constants");
+      }
+      break;
+   case MESA_GEOMETRY_PROGRAM:
+      if (_mesa_bitcount(prog->SamplersUsed) >
+          ctx->Const.GeometryProgram.MaxGeometryTextureImageUnits) {
+         fail_link(shader_program, "Too many geometry shader texture samplers");
+      }
+      if (prog->Parameters->NumParameters >
+          ctx->Const.GeometryProgram.MaxParameters) {
+         fail_link(shader_program, "Too many geometry shader constants");
+      }
+      break;
+   case GL_FRAGMENT_PROGRAM_ARB:
+      if (_mesa_bitcount(prog->SamplersUsed) >
+          ctx->Const.MaxTextureImageUnits) {
+         fail_link(shader_program, "Too many fragment shader texture samplers");
+      }
+      if (prog->Parameters->NumParameters >
+          ctx->Const.FragmentProgram.MaxParameters) {
+         fail_link(shader_program, "Too many fragment shader constants");
+      }
+      break;
+   default:
+      _mesa_problem(ctx, "unexpected program type in check_resources()");
+   }
+}
+
+
+
 struct uniform_sort {
    struct gl_uniform *u;
    int pos;
@@ -3026,6 +3082,8 @@ get_mesa_program(struct gl_context *ctx,
    do_set_program_inouts(shader->ir, prog);
    count_resources(prog);
 
+   check_resources(ctx, shader_program, prog);
+
    _mesa_reference_program(ctx, &shader->Program, prog);
 
    if ((ctx->Shader.Flags & GLSL_NO_OPT) == 0) {