From 45cfe9822d8d4401c7998351e54a159a19c09bad Mon Sep 17 00:00:00 2001
From: Matt Arsenault <Matthew.Arsenault@amd.com>
Date: Fri, 22 Feb 2019 19:03:31 +0000
Subject: [PATCH] LiveIntervals: Add removeAllRegUnitsForPhysReg

Convenience wrapper for removing the reg units of
a physical register.

llvm-svn: 354685
---
 llvm/include/llvm/CodeGen/LiveIntervals.h | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/llvm/include/llvm/CodeGen/LiveIntervals.h b/llvm/include/llvm/CodeGen/LiveIntervals.h
index d0791bec5c41..588b0f9cf39c 100644
--- a/llvm/include/llvm/CodeGen/LiveIntervals.h
+++ b/llvm/include/llvm/CodeGen/LiveIntervals.h
@@ -417,6 +417,15 @@ class VirtRegMap;
       RegUnitRanges[Unit] = nullptr;
     }
 
+    /// Remove associated live ranges for the register units associated with \p
+    /// Reg. Subsequent uses should rely on on-demand recomputation.  \note This
+    /// method can result in inconsistent liveness tracking if multiple phyical
+    /// registers share a regunit, and should be used cautiously.
+    void removeAllRegUnitsForPhysReg(unsigned Reg) {
+      for (MCRegUnitIterator Units(Reg, TRI); Units.isValid(); ++Units)
+        removeRegUnit(*Units);
+    }
+
     /// Remove value numbers and related live segments starting at position
     /// \p Pos that are part of any liverange of physical register \p Reg or one
     /// of its subregisters.