8 files changed, 203 insertions, 26 deletions

diff --git a/src/mesa/shader/prog_parameter.c b/src/mesa/shader/prog_parameter.c
index 25bb4f3d44..aac488c79a 100644
--- a/src/mesa/shader/prog_parameter.c
+++ b/src/mesa/shader/prog_parameter.c
@@ -376,7 +376,8 @@ _mesa_add_sampler(struct gl_program_parameter_list *paramList,
  */
 GLint
 _mesa_add_varying(struct gl_program_parameter_list *paramList,
-                  const char *name, GLuint size, GLbitfield flags)
+                  const char *name, GLuint size, GLenum datatype,
+                  GLbitfield flags)
 {
    GLint i = _mesa_lookup_parameter_index(paramList, -1, name);
    if (i >= 0 && paramList->Parameters[i].Type == PROGRAM_VARYING) {
@@ -386,7 +387,7 @@ _mesa_add_varying(struct gl_program_parameter_list *paramList,
    else {
       /*assert(size == 4);*/
       i = _mesa_add_parameter(paramList, PROGRAM_VARYING, name,
-                              size, GL_NONE, NULL, NULL, flags);
+                              size, datatype, NULL, NULL, flags);
       return i;
    }
 }
diff --git a/src/mesa/shader/prog_parameter.h b/src/mesa/shader/prog_parameter.h
index 1111c85976..cc3378ae20 100644
--- a/src/mesa/shader/prog_parameter.h
+++ b/src/mesa/shader/prog_parameter.h
@@ -146,7 +146,8 @@ _mesa_add_sampler(struct gl_program_parameter_list *paramList,
 
 extern GLint
 _mesa_add_varying(struct gl_program_parameter_list *paramList,
-                  const char *name, GLuint size, GLbitfield flags);
+                  const char *name, GLuint size, GLenum datatype,
+                  GLbitfield flags);
 
 extern GLint
 _mesa_add_attribute(struct gl_program_parameter_list *paramList,
diff --git a/src/mesa/shader/shader_api.c b/src/mesa/shader/shader_api.c
index 36fe0a1bb7..4ff032d4ec 100644
--- a/src/mesa/shader/shader_api.c
+++ b/src/mesa/shader/shader_api.c
@@ -782,8 +782,11 @@ _mesa_detach_shader(GLcontext *ctx, GLuint program, GLuint shader)
 }
 
 
-static GLint
-sizeof_glsl_type(GLenum type)
+/**
+ * Return the size of the given GLSL datatype, in floats (components).
+ */
+GLint
+_mesa_sizeof_glsl_type(GLenum type)
 {
    switch (type) {
    case GL_FLOAT:
@@ -828,7 +831,7 @@ sizeof_glsl_type(GLenum type)
    case GL_FLOAT_MAT4x3:
       return 16;  /* four float[4] vectors */
    default:
-      _mesa_problem(NULL, "Invalid type in sizeof_glsl_type()");
+      _mesa_problem(NULL, "Invalid type in _mesa_sizeof_glsl_type()");
       return 1;
    }
 }
@@ -912,7 +915,7 @@ _mesa_get_active_attrib(GLcontext *ctx, GLuint program, GLuint index,
 
    if (size)
       *size = attribs->Parameters[index].Size
-         / sizeof_glsl_type(attribs->Parameters[index].DataType);
+         / _mesa_sizeof_glsl_type(attribs->Parameters[index].DataType);
 
    if (type)
       *type = attribs->Parameters[index].DataType;
@@ -987,7 +990,7 @@ _mesa_get_active_uniform(GLcontext *ctx, GLuint program, GLuint index,
    }
 
    if (size) {
-      GLint typeSize = sizeof_glsl_type(param->DataType);
+      GLint typeSize = _mesa_sizeof_glsl_type(param->DataType);
       if ((GLint) param->Size > typeSize) {
          /* This is an array.
           * Array elements are placed on vector[4] boundaries so they're
@@ -1519,6 +1522,12 @@ _mesa_link_program(GLcontext *ctx, GLuint program)
    if (!shProg)
       return;
 
+   if (ctx->TransformFeedback.Active && shProg == ctx->Shader.CurrentProgram) {
+      _mesa_error(ctx, GL_INVALID_OPERATION,
+                  "glLinkProgram(transform feedback active");
+      return;
+   }
+
    FLUSH_VERTICES(ctx, _NEW_PROGRAM);
 
    _slang_link(ctx, program, shProg);
@@ -1583,6 +1592,12 @@ _mesa_use_program(GLcontext *ctx, GLuint program)
 {
    struct gl_shader_program *shProg;
 
+   if (ctx->TransformFeedback.Active) {
+      _mesa_error(ctx, GL_INVALID_OPERATION,
+                  "glUseProgram(transform feedback active)");
+      return;
+   }
+
    if (ctx->Shader.CurrentProgram &&
        ctx->Shader.CurrentProgram->Name == program) {
       /* no-op */
@@ -1771,7 +1786,7 @@ set_program_uniform(GLcontext *ctx, struct gl_program *program,
       const GLboolean isUniformBool = is_boolean_type(param->DataType);
       const GLboolean areIntValues = is_integer_type(type);
       const GLint slots = (param->Size + 3) / 4;
-      const GLint typeSize = sizeof_glsl_type(param->DataType);
+      const GLint typeSize = _mesa_sizeof_glsl_type(param->DataType);
       GLsizei k, i;
 
       if ((GLint) param->Size > typeSize) {
@@ -1960,7 +1975,7 @@ set_program_uniform_matrix(GLcontext *ctx, struct gl_program *program,
    GLuint src = 0;
    const struct gl_program_parameter * param = &program->Parameters->Parameters[index];
    const GLuint slots = (param->Size + 3) / 4;
-   const GLint typeSize = sizeof_glsl_type(param->DataType);
+   const GLint typeSize = _mesa_sizeof_glsl_type(param->DataType);
    GLint nr, nc;
 
    /* check that the number of rows, columns is correct */
diff --git a/src/mesa/shader/shader_api.h b/src/mesa/shader/shader_api.h
index 3ed52747cd..597f0b8e75 100644
--- a/src/mesa/shader/shader_api.h
+++ b/src/mesa/shader/shader_api.h
@@ -47,6 +47,9 @@ extern void
 _mesa_copy_string(GLchar *dst, GLsizei maxLength,
                   GLsizei *length, const GLchar *src);
 
+extern GLint
+_mesa_sizeof_glsl_type(GLenum type);
+
 
 /*
 extern struct gl_shader_program *
diff --git a/src/mesa/shader/slang/slang_builtin.c b/src/mesa/shader/slang/slang_builtin.c
index 791e751526..b7bf4e06dc 100644
--- a/src/mesa/shader/slang/slang_builtin.c
+++ b/src/mesa/shader/slang/slang_builtin.c
@@ -752,7 +752,6 @@ static const struct input_info fragInputs[] = {
    { "gl_Color", FRAG_ATTRIB_COL0, GL_FLOAT_VEC4, SWIZZLE_NOOP },
    { "gl_SecondaryColor", FRAG_ATTRIB_COL1, GL_FLOAT_VEC4, SWIZZLE_NOOP },
    { "gl_TexCoord", FRAG_ATTRIB_TEX0, GL_FLOAT_VEC4, SWIZZLE_NOOP },
-   /* note: we're packing several quantities into the fogcoord vector */
    { "gl_FogFragCoord", FRAG_ATTRIB_FOGC, GL_FLOAT, SWIZZLE_XXXX },
    { "gl_FrontFacing", FRAG_ATTRIB_FACE, GL_FLOAT, SWIZZLE_XXXX },
    { "gl_PointCoord", FRAG_ATTRIB_PNTC, GL_FLOAT_VEC2, SWIZZLE_XYZW },
@@ -839,27 +838,28 @@ struct output_info
 {
    const char *Name;
    GLuint Attrib;
+   GLenum Type;
 };
 
 /** Predefined vertex shader outputs */
 static const struct output_info vertOutputs[] = {
-   { "gl_Position", VERT_RESULT_HPOS },
-   { "gl_FrontColor", VERT_RESULT_COL0 },
-   { "gl_BackColor", VERT_RESULT_BFC0 },
-   { "gl_FrontSecondaryColor", VERT_RESULT_COL1 },
-   { "gl_BackSecondaryColor", VERT_RESULT_BFC1 },
-   { "gl_TexCoord", VERT_RESULT_TEX0 },
-   { "gl_FogFragCoord", VERT_RESULT_FOGC },
-   { "gl_PointSize", VERT_RESULT_PSIZ },
-   { NULL, 0 }
+   { "gl_Position", VERT_RESULT_HPOS, GL_FLOAT_VEC4 },
+   { "gl_FrontColor", VERT_RESULT_COL0, GL_FLOAT_VEC4 },
+   { "gl_BackColor", VERT_RESULT_BFC0, GL_FLOAT_VEC4 },
+   { "gl_FrontSecondaryColor", VERT_RESULT_COL1, GL_FLOAT_VEC4 },
+   { "gl_BackSecondaryColor", VERT_RESULT_BFC1, GL_FLOAT_VEC4 },
+   { "gl_TexCoord", VERT_RESULT_TEX0, GL_FLOAT_VEC4 },
+   { "gl_FogFragCoord", VERT_RESULT_FOGC, GL_FLOAT },
+   { "gl_PointSize", VERT_RESULT_PSIZ, GL_FLOAT },
+   { NULL, 0, GL_NONE }
 };
 
 /** Predefined fragment shader outputs */
 static const struct output_info fragOutputs[] = {
-   { "gl_FragColor", FRAG_RESULT_COLOR },
-   { "gl_FragDepth", FRAG_RESULT_DEPTH },
-   { "gl_FragData", FRAG_RESULT_DATA0 },
-   { NULL, 0 }
+   { "gl_FragColor", FRAG_RESULT_COLOR, GL_FLOAT_VEC4 },
+   { "gl_FragDepth", FRAG_RESULT_DEPTH, GL_FLOAT },
+   { "gl_FragData", FRAG_RESULT_DATA0, GL_FLOAT_VEC4 },
+   { NULL, 0, GL_NONE }
 };
 
 
@@ -895,3 +895,43 @@ _slang_output_index(const char *name, GLenum target)
    }
    return -1;
 }
+
+
+/**
+ * Given a VERT_RESULT_x index, return the corresponding string name.
+ */
+const char *
+_slang_vertex_output_name(gl_vert_result index)
+{
+   if (index < Elements(vertOutputs))
+      return vertOutputs[index].Name;
+   else
+      return NULL;
+}
+
+
+/**
+ * Given a FRAG_RESULT_x index, return the corresponding string name.
+ */
+const char *
+_slang_fragment_output_name(gl_frag_result index)
+{
+   if (index < Elements(fragOutputs))
+      return fragOutputs[index].Name;
+   else
+      return NULL;
+}
+
+
+/**
+ * Given a VERT_RESULT_x index, return the corresponding varying
+ * var's datatype.
+ */
+GLenum
+_slang_vertex_output_type(gl_vert_result index)
+{
+   if (index < Elements(vertOutputs))
+      return vertOutputs[index].Type;
+   else
+      return GL_NONE;
+}
diff --git a/src/mesa/shader/slang/slang_builtin.h b/src/mesa/shader/slang/slang_builtin.h
index f814d11ac7..c3021ca33c 100644
--- a/src/mesa/shader/slang/slang_builtin.h
+++ b/src/mesa/shader/slang/slang_builtin.h
@@ -51,4 +51,14 @@ extern GLenum
 _slang_vert_attrib_type(GLuint attrib);
 
 
+const char *
+_slang_vertex_output_name(gl_vert_result index);
+
+const char *
+_slang_fragment_output_name(gl_frag_result index);
+
+GLenum
+_slang_vertex_output_type(gl_vert_result index);
+
+
 #endif /* SLANG_BUILTIN_H */
diff --git a/src/mesa/shader/slang/slang_codegen.c b/src/mesa/shader/slang/slang_codegen.c
index ecb2f6d5c1..fa79632c18 100644
--- a/src/mesa/shader/slang/slang_codegen.c
+++ b/src/mesa/shader/slang/slang_codegen.c
@@ -5130,7 +5130,7 @@ _slang_codegen_global_variable(slang_assemble_ctx *A, slang_variable *var,
             flags |= PROG_PARAM_BIT_INVARIANT;
 
          varyingLoc = _mesa_add_varying(prog->Varying, varName,
-                                        totalSize, flags);
+                                        totalSize, GL_NONE, flags);
          swizzle = _slang_var_swizzle(size, 0);
          store = _slang_new_ir_storage_swz(PROGRAM_VARYING, varyingLoc,
                                            totalSize, swizzle);
diff --git a/src/mesa/shader/slang/slang_link.c b/src/mesa/shader/slang/slang_link.c
index 7c7bfbdbc5..f71fde1d72 100644
--- a/src/mesa/shader/slang/slang_link.c
+++ b/src/mesa/shader/slang/slang_link.c
@@ -87,6 +87,107 @@ bits_agree(GLbitfield flags1, GLbitfield flags2, GLbitfield bit)
 
 
 /**
+ * Examine the outputs/varyings written by the vertex shader and
+ * append the names of those outputs onto the Varyings list.
+ * This will only capture the pre-defined/built-in varyings like
+ * gl_Position, not user-defined varyings.
+ */
+static void
+update_varying_var_list(GLcontext *ctx, struct gl_shader_program *shProg)
+{
+   if (shProg->VertexProgram) {
+      GLbitfield64 written = shProg->VertexProgram->Base.OutputsWritten;
+      GLuint i;
+      for (i = 0; written && i < VERT_RESULT_MAX; i++) {
+         if (written & BITFIELD64_BIT(i)) {
+            const char *name = _slang_vertex_output_name(i);            
+            if (name)
+               _mesa_add_varying(shProg->Varying, name, 1, GL_FLOAT_VEC4, 0x0);
+            written &= ~BITFIELD64_BIT(i);
+         }
+      }
+   }
+}
+
+
+/**
+ * Do link error checking related to transform feedback.
+ */
+static GLboolean
+link_transform_feedback(GLcontext *ctx, struct gl_shader_program *shProg)
+{
+   GLbitfield varyingMask;
+   GLuint totalComps, maxComps, i;
+
+   if (shProg->TransformFeedback.NumVarying == 0) {
+      /* nothing to do */
+      return GL_TRUE;
+   }
+
+   /* Check that there's a vertex shader */
+   if (shProg->TransformFeedback.NumVarying > 0 &&
+       !shProg->VertexProgram) {
+      link_error(shProg, "Transform feedback without vertex shader");
+      return GL_FALSE;
+   }
+
+   /* Check that all named variables exist, and that none are duplicated.
+    * Also, build a count of the number of varying components to feedback.
+    */
+   totalComps = 0;
+   varyingMask = 0x0;
+   for (i = 0; i < shProg->TransformFeedback.NumVarying; i++) {
+      const GLchar *name = shProg->TransformFeedback.VaryingNames[i];
+      GLint v = _mesa_lookup_parameter_index(shProg->Varying, -1, name);
+      struct gl_program_parameter *p;
+
+      if (v < 0) {
+         char msg[100];
+         _mesa_snprintf(msg, sizeof(msg),
+                        "vertex shader does not emit %s", name);
+         link_error(shProg, msg);
+         return GL_FALSE;
+      }
+
+      assert(v < MAX_VARYING);
+
+      /* already seen this varying name? */
+      if (varyingMask & (1 << v)) {
+         char msg[100];
+         _mesa_snprintf(msg, sizeof(msg),
+                        "duplicated transform feedback varying name: %s",
+                        name);
+         link_error(shProg, msg);
+         return GL_FALSE;
+      }
+
+      varyingMask |= (1 << v);
+
+      p = &shProg->Varying->Parameters[v];
+      
+      totalComps += _mesa_sizeof_glsl_type(p->DataType);
+   }
+
+   if (shProg->TransformFeedback.BufferMode == GL_INTERLEAVED_ATTRIBS)
+      maxComps = ctx->Const.MaxTransformFeedbackInterleavedComponents;
+   else
+      maxComps = ctx->Const.MaxTransformFeedbackSeparateComponents;
+
+   /* check max varying components against the limit */
+   if (totalComps > maxComps) {
+      char msg[100];
+      _mesa_snprintf(msg, sizeof(msg),
+                     "Too many feedback components: %u, max is %u",
+                     totalComps, maxComps);
+      link_error(shProg, msg);
+      return GL_FALSE;
+   }
+
+   return GL_TRUE;
+}
+
+
+/**
  * Linking varying vars involves rearranging varying vars so that the
  * vertex program's output varyings matches the order of the fragment
  * program's input varyings.
@@ -157,7 +258,7 @@ link_varying_vars(GLcontext *ctx,
       else {
          /* not already in linked list */
          j = _mesa_add_varying(shProg->Varying, var->Name, var->Size,
-                               var->Flags);
+                               var->DataType, var->Flags);
       }
 
       if (shProg->Varying->NumParameters > ctx->Const.MaxVarying) {
@@ -866,6 +967,12 @@ _slang_link(GLcontext *ctx,
       }         
    }
 
+   update_varying_var_list(ctx, shProg);
+
+   /* checks related to transform feedback */
+   if (!link_transform_feedback(ctx, shProg)) {
+      return;
+   }
 
    if (fragProg && shProg->FragmentProgram) {
       /* Compute initial program's TexturesUsed info */