commit fbc247367a86e8a711584801586ec9616268d889
author David Green <david.green@arm.com> Tue Mar 26 09:48:06 2024 +0000
committer GitHub <noreply@github.com> Tue Mar 26 09:48:06 2024 +0000
tree ffd2b9caab01a89344f730bbe7267ffcf92de334
parent 4fa736ba41fce885047bd5a242230b216ea85c70

[AArch64][GlobalISel] Legalization for small anyext/sext/zext (#86438)

Similar to #85625, some of the codegen is still far from optimal but
this helps fix quite a few fallback cases.

llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp

diff --git a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
index 1b25da8..c3a23ea 100644
--- a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
@@ -5421,14 +5421,22 @@
   case TargetOpcode::G_FPTOUI:
   case TargetOpcode::G_SITOFP:
   case TargetOpcode::G_UITOFP: {
-    if (TypeIdx != 0)
-      return UnableToLegalize;
     Observer.changingInstr(MI);
-    LLT SrcTy = LLT::fixed_vector(
-        MoreTy.getNumElements(),
-        MRI.getType(MI.getOperand(1).getReg()).getElementType());
-    moreElementsVectorSrc(MI, SrcTy, 1);
-    moreElementsVectorDst(MI, MoreTy, 0);
+    LLT SrcExtTy;
+    LLT DstExtTy;
+    if (TypeIdx == 0) {
+      DstExtTy = MoreTy;
+      SrcExtTy = LLT::fixed_vector(
+          MoreTy.getNumElements(),
+          MRI.getType(MI.getOperand(1).getReg()).getElementType());
+    } else {
+      DstExtTy = LLT::fixed_vector(
+          MoreTy.getNumElements(),
+          MRI.getType(MI.getOperand(0).getReg()).getElementType());
+      SrcExtTy = MoreTy;
+    }
+    moreElementsVectorSrc(MI, SrcExtTy, 1);
+    moreElementsVectorDst(MI, DstExtTy, 0);
     Observer.changedInstr(MI);
     return Legalized;
   }