[llvm] [DirectX][docs] Expand DXILArchitecture documentation (PR #84077)

[Justin Bogner via llvm-commits]

================
@@ -89,6 +89,52 @@ leverage LLVM's current bitcode libraries to do a lot of the work, but
 it's possible that at some point in the future it will need to be
 completely separate as modern LLVM bitcode evolves.
 
+DirectX Backend Flow
+--------------------
+
+The code generation flow for DXIL is broken into a series of passes. The passes
+are grouped into two flows:
+
+#. Generating DXIL IR.
+#. Generating DXIL Binary.
+
+The passes to generate DXIL IR follow the flow:
+
+DXILOpLowering -> DXILPrepare -> DXILTranslateMetadata
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bogner wrote:

This probably renders more readably if you indent it (it'll treat it as a block quote that way, rather than a paragraph)

https://github.com/llvm/llvm-project/pull/84077