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diff --git a/docs/shading.html b/docs/shading.html index cb2c1c3209..40a6d7ac90 100644 --- a/docs/shading.html +++ b/docs/shading.html @@ -67,7 +67,7 @@ All other major features of the shading language should function. <li>The quality of generated code is pretty good, register usage is fair. <li>Shader error detection and reporting of errors (InfoLog) is not very good yet. -<li>There are massive memory leaks in the compiler. +<li>There are known memory leaks in the compiler. </ul> <p> @@ -236,6 +236,50 @@ The final vertex and fragment programs may be interpreted in software (see drivers/dri/i915/i915_fragprog.c for example). </p> +<h3>Code Generation Options</h3> + +<p> +Internally, there are several options that control the compiler's code +generation and instruction selection. +These options are seen in the gl_shader_state struct and may be set +by the device driver to indicate its preferences: + +<pre> +struct gl_shader_state +{ + ... + /** Driver-selectable options: */ + GLboolean EmitHighLevelInstructions; + GLboolean EmitCondCodes; + GLboolean EmitComments; +}; +</pre> + +<ul> +<li>EmitHighLevelInstructions +<br> +This option controls instruction selection for loops and conditionals. +If the option is set high-level IF/ELSE/ENDIF, LOOP/ENDLOOP, CONT/BRK +instructions will be emitted. +Otherwise, those constructs will be implemented with BRA instructions. +</li> + +<li>EmitCondCodes +<br> +If set, condition codes (ala GL_NV_fragment_program) will be used for +branching and looping. +Otherwise, ordinary registers will be used (the IF instruction will +examine the first operand's X component and do the if-part if non-zero). +This option is only relevant if EmitHighLevelInstructions is set. +</li> + +<li>EmitComments +<br> +If set, instructions will be annoted with comments to help with debugging. +Extra NOP instructions will also be inserted. +</br> + +</ul> </BODY> |