From 03698deb25215bf3b4aa2e3ff731ea38923a928c Mon Sep 17 00:00:00 2001
From: Lang Hames <lhames@gmail.com>
Date: Tue, 14 Feb 2012 19:17:48 +0000
Subject: [PATCH] Update MachineVerifier to check the new physreg live-in
 rules.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150496 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/MachineVerifier.cpp | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/lib/CodeGen/MachineVerifier.cpp b/lib/CodeGen/MachineVerifier.cpp
index 0a2c2f82967..065f2527ca2 100644
--- a/lib/CodeGen/MachineVerifier.cpp
+++ b/lib/CodeGen/MachineVerifier.cpp
@@ -75,6 +75,7 @@ namespace {
     const MachineInstr *FirstTerminator;
 
     BitVector regsReserved;
+    BitVector regsAllocatable;
     RegSet regsLive;
     RegVector regsDefined, regsDead, regsKilled;
     RegSet regsLiveInButUnused;
@@ -175,6 +176,10 @@ namespace {
       return Reg < regsReserved.size() && regsReserved.test(Reg);
     }
 
+    bool isAllocatable(unsigned Reg) {
+      return Reg < regsAllocatable.size() && regsAllocatable.test(Reg);
+    }
+
     // Analysis information if available
     LiveVariables *LiveVars;
     LiveIntervals *LiveInts;
@@ -380,6 +385,9 @@ void MachineVerifier::visitMachineFunctionBefore() {
       regsReserved.set(*Sub);
     }
   }
+
+  regsAllocatable = TRI->getAllocatableSet(*MF);
+
   markReachable(&MF->front());
 }
 
@@ -397,6 +405,20 @@ void
 MachineVerifier::visitMachineBasicBlockBefore(const MachineBasicBlock *MBB) {
   FirstTerminator = 0;
 
+  if (MRI->isSSA()) {
+    // If this block has allocatable physical registers live-in, check that
+    // it is an entry block or landing pad.
+    for (MachineBasicBlock::livein_iterator LI = MBB->livein_begin(),
+           LE = MBB->livein_end();
+         LI != LE; ++LI) {
+      unsigned reg = *LI;
+      if (isAllocatable(reg) && !MBB->isLandingPad() &&
+          MBB != MBB->getParent()->begin()) {
+        report("MBB has allocable live-in, but isn't entry or landing-pad.", MBB);
+      }
+    }
+  }
+
   // Count the number of landing pad successors.
   SmallPtrSet<MachineBasicBlock*, 4> LandingPadSuccs;
   for (MachineBasicBlock::const_succ_iterator I = MBB->succ_begin(),