From: Chris Lattner <sabre@nondot.org>
Date: Fri, 8 Sep 2006 20:21:31 +0000 (+0000)
Subject: Non-allocatable physregs can be killed and dead, but don't treat them as
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=0c5b8dac794b23ac7f84acdc6d2661edb28ed5c8;p=oota-llvm.git

Non-allocatable physregs can be killed and dead, but don't treat them as
safe for later allocation.  This fixes McCat/18-imp with llc-beta.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30204 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/RegAllocLocal.cpp b/lib/CodeGen/RegAllocLocal.cpp
index 8e7c1fe2a02..5b9186dbe35 100644
--- a/lib/CodeGen/RegAllocLocal.cpp
+++ b/lib/CodeGen/RegAllocLocal.cpp
@@ -580,6 +580,9 @@ void RA::AllocateBasicBlock(MachineBasicBlock &MBB) {
         unsigned &PhysRegSlot = getVirt2PhysRegMapSlot(VirtReg);
         PhysReg = PhysRegSlot;
         PhysRegSlot = 0;
+      } else if (PhysRegsUsed[PhysReg] == -2) {
+        // Unallocatable register dead, ignore.
+        continue;
       }
 
       if (PhysReg) {
@@ -669,6 +672,9 @@ void RA::AllocateBasicBlock(MachineBasicBlock &MBB) {
         PhysReg = PhysRegSlot;
         assert(PhysReg != 0);
         PhysRegSlot = 0;
+      } else if (PhysRegsUsed[PhysReg] == -2) {
+        // Unallocatable register dead, ignore.
+        continue;
       }
 
       if (PhysReg) {