[PATCH] D107630: [docs][GlobalISel]Adding info for G_JUMP_TABLE generic opcode

[PoojaYadav via Phabricator via llvm-commits]

pooja2299 created this revision.
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Added description of jump table and G_JUMP_TABLE opcode.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D107630

Files:
  llvm/docs/GlobalISel/GenericOpcode.rst


Index: llvm/docs/GlobalISel/GenericOpcode.rst
===================================================================
--- llvm/docs/GlobalISel/GenericOpcode.rst
+++ llvm/docs/GlobalISel/GenericOpcode.rst
@@ -798,9 +798,21 @@
 G_JUMP_TABLE
 ^^^^^^^^^^^^
 
-.. caution::
+This generic jump table opcode generates a pointer to the address of the jump 
+table specified by the source operand, which is a jump table index. (A jump 
+table is an array of addresses the CPU should jump to based on certain 
+conditions.)
+It can be used in conjunction with G_BRJT opcode to support jump table codegen 
+with GlobalISel.
+
+.. code-block:: none
+
+  %dst:_(s32) = G_JUMP_TABLE %jump-table.0
+
+The above example shows assignment of pointer to jump table of given index.
+Source operand must be a jump table index.
+Destination operand must have a pointer type. 
 
-  I found no documentation for this instruction at the time of writing.
 
 G_INTRINSIC, G_INTRINSIC_W_SIDE_EFFECTS
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^


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