[llvm] [X86] Use RORX over SHR imm (PR #77964)

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github-actions[bot] wrote:

<!--LLVM CODE FORMAT COMMENT: {clang-format}-->


:warning: C/C++ code formatter, clang-format found issues in your code. :warning:

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``````````bash
git-clang-format --diff fc6faa1113e9069f41b5500db051210af0eea843 8a4753177d47dbac3ce6a679065d7a11343a69c5 -- llvm/lib/Target/X86/X86ISelDAGToDAG.cpp
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View the diff from clang-format here.
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``````````diff
diff --git a/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp b/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp
index 09724363e1..e59b895df7 100644
--- a/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp
+++ b/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp
@@ -4237,28 +4237,38 @@ bool X86DAGToDAGISel::rightShiftUncloberFlags(SDNode *N) {
   printf("Not vector\n");
 
   unsigned OpSize;
-       if (VT == MVT::i64) OpSize = 64;
-  else if (VT == MVT::i32) OpSize = 32;
-  else if (VT == MVT::i16) OpSize = 16;
-  else if (VT == MVT::i8) return false; // i8 shift can't be truncated.
-  else llvm_unreachable("Unexpected shift size");
+  if (VT == MVT::i64)
+    OpSize = 64;
+  else if (VT == MVT::i32)
+    OpSize = 32;
+  else if (VT == MVT::i16)
+    OpSize = 16;
+  else if (VT == MVT::i8)
+    return false; // i8 shift can't be truncated.
+  else
+    llvm_unreachable("Unexpected shift size");
 
   printf("Good OpSize\n");
 
   unsigned TruncateSize = 0;
   // This only works when the result is truncated.
   for (const SDNode *User : N->uses()) {
-    //printf("Looking at a use. TargetOpcode is %u\n", User->isTargetOpcode());
+    // printf("Looking at a use. TargetOpcode is %u\n", User->isTargetOpcode());
     auto name = User->getOperationName(CurDAG);
-    printf("Looking at a thing %s %u %u\n", name.c_str(), User->getOpcode(), TargetOpcode::EXTRACT_SUBREG);
+    printf("Looking at a thing %s %u %u\n", name.c_str(), User->getOpcode(),
+           TargetOpcode::EXTRACT_SUBREG);
     if (User->getMachineOpcode() != TargetOpcode::EXTRACT_SUBREG)
       return false;
     printf("It's an EXTRACT_SUBREG\n");
     EVT TuncateType = User->getValueType(0);
-         if (TuncateType == MVT::i32) TruncateSize = std::max(TruncateSize, 32U);
-    else if (TuncateType == MVT::i16) TruncateSize = std::max(TruncateSize, 16U);
-    else if (TuncateType == MVT::i8)  TruncateSize = std::max(TruncateSize, 8U);
-    else return false;
+    if (TuncateType == MVT::i32)
+      TruncateSize = std::max(TruncateSize, 32U);
+    else if (TuncateType == MVT::i16)
+      TruncateSize = std::max(TruncateSize, 16U);
+    else if (TuncateType == MVT::i8)
+      TruncateSize = std::max(TruncateSize, 8U);
+    else
+      return false;
   }
   printf("Truncates are fine\n");
   if (TruncateSize >= OpSize)
@@ -4279,7 +4289,10 @@ bool X86DAGToDAGISel::rightShiftUncloberFlags(SDNode *N) {
   // Make the replacement.
   SDLoc DL(N);
   MVT RotateSize = OpSize == 64 ? MVT::i64 : MVT::i32;
-  SDNode* Replacement = CurDAG->getNode(ISD::ROTR, DL, RotateSize, N->getOperand(0), N->getOperand(1)).getNode();
+  SDNode *Replacement = CurDAG
+                            ->getNode(ISD::ROTR, DL, RotateSize,
+                                      N->getOperand(0), N->getOperand(1))
+                            .getNode();
   ReplaceNode(N, Replacement);
   CurDAG->RemoveDeadNode(N);
   SelectCode(Replacement);

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https://github.com/llvm/llvm-project/pull/77964