mesa: add skeleton code for DrawPixels/CopyPixels/Bitmap precomputed validation

This is for precomputing draw time validation in state changes.
The next commit will use this.

Reviewed-by: Zoltán Böszörményi <zboszor@gmail.com>
Reviewed-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8798>

src/mesa/main/draw_validate.c

@@ -249,14 +249,22 @@ _mesa_update_valid_to_render_state(struct gl_context *ctx)
 {
    struct gl_pipeline_object *shader = ctx->_Shader;
    unsigned mask = ctx->SupportedPrimMask;
+   bool drawpix_valid = true;
 
    if (_mesa_is_no_error_enabled(ctx)) {
       ctx->ValidPrimMask = mask;
+      ctx->DrawPixValid = drawpix_valid;
       return;
    }
 
    /* Start with an empty mask and set this to the trimmed mask at the end. */
    ctx->ValidPrimMask = 0;
+   ctx->DrawPixValid = false;
+
+   /* TODO: insert code here */
+
+   /* DrawPixels/CopyPixels/Bitmap is valid after this point. */
+   ctx->DrawPixValid = true;
 
    /* Section 11.2 (Tessellation) of the ES 3.2 spec says:
     *

src/mesa/main/drawpix.c

@@ -77,6 +77,11 @@ _mesa_DrawPixels( GLsizei width, GLsizei height,
       goto end;      /* the error code was recorded */
    }
 
+   if (!ctx->DrawPixValid) {
+      _mesa_error(ctx, GL_INVALID_OPERATION, "glDrawPixels");
+      goto end;
+   }
+
    /* GL 3.0 introduced a new restriction on glDrawPixels() over what was in
     * GL_EXT_texture_integer.  From section 3.7.4 ("Rasterization of Pixel
     * Rectangles) on page 151 of the GL 3.0 specification:
@@ -243,6 +248,11 @@ _mesa_CopyPixels( GLint srcx, GLint srcy, GLsizei width, GLsizei height,
       goto end;      /* the error code was recorded */
    }
 
+   if (!ctx->DrawPixValid) {
+      _mesa_error(ctx, GL_INVALID_OPERATION, "glCopyPixels");
+      goto end;
+   }
+
    /* Check read buffer's status (draw buffer was already checked) */
    if (ctx->ReadBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
       _mesa_error(ctx, GL_INVALID_FRAMEBUFFER_OPERATION_EXT,
@@ -327,6 +337,11 @@ _mesa_Bitmap( GLsizei width, GLsizei height,
       return;
    }
 
+   if (!ctx->DrawPixValid) {
+      _mesa_error(ctx, GL_INVALID_OPERATION, "glBitmap");
+      return;
+   }
+
    if (ctx->RasterDiscard)
       return;
 

src/mesa/main/mtypes.h

@@ -5234,6 +5234,11 @@ struct gl_context
     */
    GLbitfield ValidPrimMask;
 
+   /**
+    * Whether DrawPixels/CopyPixels/Bitmap are valid to render.
+    */
+   bool DrawPixValid;
+
    /** \name The various 4x4 matrix stacks */
    /*@{*/
    struct gl_matrix_stack ModelviewMatrixStack;