From: Craig Topper <craig.topper@intel.com>
Date: Thu, 20 Dec 2018 01:32:06 +0000 (+0000)
Subject: [X86] Disable custom widening of signed/unsigned add/sub saturation intrinsics under... 
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=32e66b72648f066ac2c4aeda10ed0dcf36ac88ff;p=llvm

[X86] Disable custom widening of signed/unsigned add/sub saturation intrinsics under -x86-experimental-vector-widening-legalization.

Generic legalization should take care of this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349714 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index e381d0cace0..10d96131c81 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -837,13 +837,16 @@ X86TargetLowering::X86TargetLowering(const X86TargetMachine &TM,
     setOperationAction(ISD::SADDSAT,            MVT::v8i16, Legal);
     setOperationAction(ISD::USUBSAT,            MVT::v8i16, Legal);
     setOperationAction(ISD::SSUBSAT,            MVT::v8i16, Legal);
-    // Use widening instead of promotion.
-    for (auto VT : { MVT::v8i8, MVT::v4i8, MVT::v2i8,
-                     MVT::v4i16, MVT::v2i16 }) {
-      setOperationAction(ISD::UADDSAT, VT, Custom);
-      setOperationAction(ISD::SADDSAT, VT, Custom);
-      setOperationAction(ISD::USUBSAT, VT, Custom);
-      setOperationAction(ISD::SSUBSAT, VT, Custom);
+
+    if (!ExperimentalVectorWideningLegalization) {
+      // Use widening instead of promotion.
+      for (auto VT : { MVT::v8i8, MVT::v4i8, MVT::v2i8,
+                       MVT::v4i16, MVT::v2i16 }) {
+        setOperationAction(ISD::UADDSAT, VT, Custom);
+        setOperationAction(ISD::SADDSAT, VT, Custom);
+        setOperationAction(ISD::USUBSAT, VT, Custom);
+        setOperationAction(ISD::SSUBSAT, VT, Custom);
+      }
     }
 
     setOperationAction(ISD::INSERT_VECTOR_ELT,  MVT::v8i16, Custom);