commit b6137063ebda8a99f6b6f7c0c94b1cd3ad1c67d4
author Ahmed Bougacha <ahmed.bougacha@gmail.com> Mon Jan 23 21:10:14 2017 +0000
committer Ahmed Bougacha <ahmed.bougacha@gmail.com> Mon Jan 23 21:10:14 2017 +0000
tree ac733a55e82ed71c51dd7535b23e5fc72dfc6e3d
parent cfb384d39d09e4bf4e79bb0436c25e77f5d4b063

[AArch64][GlobalISel] Legalize narrow scalar fp->int conversions.

Since we're now avoiding operations using narrow scalar integer types,
we have to legalize the integer side of the FP conversions.

This requires teaching the legalizer how to do that.

llvm-svn: 292828

llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp

diff --git a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
index f77d807..6da0264 100644
--- a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
@@ -273,6 +273,20 @@
     MI.eraseFromParent();
     return Legalized;
   }
+  case TargetOpcode::G_FPTOSI:
+  case TargetOpcode::G_FPTOUI: {
+    if (TypeIdx != 0)
+      return UnableToLegalize;
+
+    unsigned DstExt = MRI.createGenericVirtualRegister(WideTy);
+    MIRBuilder.buildInstr(MI.getOpcode())
+        .addDef(DstExt)
+        .addUse(MI.getOperand(1).getReg());
+
+    MIRBuilder.buildTrunc(MI.getOperand(0).getReg(), DstExt);
+    MI.eraseFromParent();
+    return Legalized;
+  }
   case TargetOpcode::G_SITOFP:
   case TargetOpcode::G_UITOFP: {
     if (TypeIdx != 1)

llvm/lib/Target/AArch64/AArch64LegalizerInfo.cpp

diff --git a/llvm/lib/Target/AArch64/AArch64LegalizerInfo.cpp b/llvm/lib/Target/AArch64/AArch64LegalizerInfo.cpp
index 9852607..871556c 100644
--- a/llvm/lib/Target/AArch64/AArch64LegalizerInfo.cpp
+++ b/llvm/lib/Target/AArch64/AArch64LegalizerInfo.cpp
@@ -151,9 +151,8 @@
     setAction({G_UITOFP, 1, Ty}, Legal);
   }
   for (auto Ty : { s1, s8, s16 }) {
-    // FIXME: These should be widened on types smaller than s32.
-    setAction({G_FPTOSI, 0, Ty}, Legal);
-    setAction({G_FPTOUI, 0, Ty}, Legal);
+    setAction({G_FPTOSI, 0, Ty}, WidenScalar);
+    setAction({G_FPTOUI, 0, Ty}, WidenScalar);
     setAction({G_SITOFP, 1, Ty}, WidenScalar);
     setAction({G_UITOFP, 1, Ty}, WidenScalar);
   }