Add some basic documentation for gallivm code

diff --git a/src/gallium/auxiliary/gallivm/gallivm.h b/src/gallium/auxiliary/gallivm/gallivm.h
index 57912a952fb0c7d8e9f5477f42a493d173ea23cc..b4d6555d2fc5ed7bb59c5b41eba0d04fa261e548 100644 (file)
--- a/src/gallium/auxiliary/gallivm/gallivm.h
+++ b/src/gallium/auxiliary/gallivm/gallivm.h
@@ -33,6 +33,16 @@
 #ifndef GALLIVM_H
 #define GALLIVM_H
 
+/*
+  LLVM representation consists of two stages - layout independent
+  intermediate representation gallivm_ir and driver specific
+  gallivm_prog. TGSI is first being translated into gallivm_ir
+  after that driver can set number of options on gallivm_ir and
+  have it compiled into gallivm_prog. gallivm_prog can be either
+  executed (assuming there's LLVM JIT backend for the current
+  target) or machine code generation can be done (assuming there's
+  a LLVM code generator for thecurrent target)
+ */
 #if defined __cplusplus
 extern "C" {
 #endif