On x86, it's safe to treat i32 load anyext as a normal i32 load. Ditto for i8 anyext load to i16.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51019 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 28 insertions, 2 deletions

diff --git a/lib/Target/X86/X86InstrInfo.td b/lib/Target/X86/X86InstrInfo.td
index 6b0a19bb4d..afe420625c 100644
--- a/lib/Target/X86/X86InstrInfo.td
+++ b/lib/Target/X86/X86InstrInfo.td
@@ -229,9 +229,35 @@ def i32immSExt8  : PatLeaf<(i32 imm), [{
 }]>;
 
 // Helper fragments for loads.
+// It's always safe to treat a anyext i16 load as a i32 load. Ditto for
+// i8 to i16.
+def loadi16 : PatFrag<(ops node:$ptr), (i16 (ld node:$ptr)), [{
+  if (LoadSDNode *LD = dyn_cast<LoadSDNode>(N)) {
+    if (LD->getAddressingMode() != ISD::UNINDEXED)
+      return false;
+    ISD::LoadExtType ExtType = LD->getExtensionType();
+    if (ExtType == ISD::NON_EXTLOAD)
+      return true;
+    if (ExtType == ISD::EXTLOAD)
+      return LD->getAlignment() >= 16;
+  }
+  return false;
+}]>;
+
+def loadi32 : PatFrag<(ops node:$ptr), (i32 (ld node:$ptr)), [{
+  if (LoadSDNode *LD = dyn_cast<LoadSDNode>(N)) {
+    if (LD->getAddressingMode() != ISD::UNINDEXED)
+      return false;
+    ISD::LoadExtType ExtType = LD->getExtensionType();
+    if (ExtType == ISD::NON_EXTLOAD)
+      return true;
+    if (ExtType == ISD::EXTLOAD)
+      return LD->getAlignment() >= 16;
+  }
+  return false;
+}]>;
+
 def loadi8  : PatFrag<(ops node:$ptr), (i8  (load node:$ptr))>;
-def loadi16 : PatFrag<(ops node:$ptr), (i16 (load node:$ptr))>;
-def loadi32 : PatFrag<(ops node:$ptr), (i32 (load node:$ptr))>;
 def loadi64 : PatFrag<(ops node:$ptr), (i64 (load node:$ptr))>;
 
 def loadf32 : PatFrag<(ops node:$ptr), (f32 (load node:$ptr))>;