[fir][NFC] Update doc for pinned attr in fir.alloca
Add descritpion for the attribute added in D110815.
Reviewed By: kiranchandramohan
Differential Revision: https://reviews.llvm.org/D110877
GitOrigin-RevId: b04dd35f0e36e48aebf28798ad0bb42f1d3baff4
diff --git a/include/flang/Optimizer/Dialect/FIROps.td b/include/flang/Optimizer/Dialect/FIROps.td
index df4451b..7da7f20 100644
--- a/include/flang/Optimizer/Dialect/FIROps.td
+++ b/include/flang/Optimizer/Dialect/FIROps.td
@@ -123,6 +123,9 @@
allocated as stack space can often be limited. A legal implementation can
convert these large stack allocations to heap allocations regardless of
whether the procedure is recursive or not.
+
+ The pinned attribute is used to flag fir.alloca operation in a specific
+ region and avoid them being hoisted in an alloca hoisting pass.
}];
let arguments = (ins
