[Attributor] Propagate known align from arguments to call sites arguments

Since the information is known we can simply use it at the call site.
This is especially useful for callbacks but also helps regular calls.

The test changes are mechanical.

1 files changed, 12 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/IPO/Attributor.cpp b/llvm/lib/Transforms/IPO/Attributor.cpp
index 9435dc72f96..c39e3ebcbeb 100644
--- a/llvm/lib/Transforms/IPO/Attributor.cpp
+++ b/llvm/lib/Transforms/IPO/Attributor.cpp
@@ -3666,6 +3666,18 @@ struct AAAlignCallSiteArgument final : AAAlignFloating {
     return AAAlignImpl::manifest(A);
   }
 
+  /// See AbstractAttribute::updateImpl(Attributor &A).
+  ChangeStatus updateImpl(Attributor &A) override {
+    ChangeStatus Changed = AAAlignFloating::updateImpl(A);
+    if (Argument *Arg = getAssociatedArgument()) {
+      const auto &ArgAlignAA = A.getAAFor<AAAlign>(
+          *this, IRPosition::argument(*Arg), /* TrackDependence */ false,
+          DepClassTy::OPTIONAL);
+      takeKnownMaximum(ArgAlignAA.getKnownAlign());
+    }
+    return Changed;
+  }
+
   /// See AbstractAttribute::trackStatistics()
   void trackStatistics() const override { STATS_DECLTRACK_CSARG_ATTR(aligned) }
 };