From 6b0cd9b9c65dc8c91827ddd926e050738ea590fd Mon Sep 17 00:00:00 2001
From: Akira Hatanaka <ahatanaka@mips.com>
Date: Thu, 14 Jun 2012 20:51:13 +0000
Subject: [PATCH] Make machine verifier check the first instruction of the last
 bundle instead of the last instruction of a basic block.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158468 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/MachineVerifier.cpp      | 16 ++++++++--------
 test/CodeGen/Mips/machineverifier.ll | 21 +++++++++++++++++++++
 2 files changed, 29 insertions(+), 8 deletions(-)
 create mode 100644 test/CodeGen/Mips/machineverifier.ll

diff --git a/lib/CodeGen/MachineVerifier.cpp b/lib/CodeGen/MachineVerifier.cpp
index 7c64fc65e60..f6858543b3a 100644
--- a/lib/CodeGen/MachineVerifier.cpp
+++ b/lib/CodeGen/MachineVerifier.cpp
@@ -476,8 +476,8 @@ MachineVerifier::visitMachineBasicBlockBefore(const MachineBasicBlock *MBB) {
         report("MBB exits via unconditional fall-through but its successor "
                "differs from its CFG successor!", MBB);
       }
-      if (!MBB->empty() && MBB->back().isBarrier() &&
-          !TII->isPredicated(&MBB->back())) {
+      if (!MBB->empty() && getBundleStart(&MBB->back())->isBarrier() &&
+          !TII->isPredicated(getBundleStart(&MBB->back()))) {
         report("MBB exits via unconditional fall-through but ends with a "
                "barrier instruction!", MBB);
       }
@@ -497,10 +497,10 @@ MachineVerifier::visitMachineBasicBlockBefore(const MachineBasicBlock *MBB) {
       if (MBB->empty()) {
         report("MBB exits via unconditional branch but doesn't contain "
                "any instructions!", MBB);
-      } else if (!MBB->back().isBarrier()) {
+      } else if (!getBundleStart(&MBB->back())->isBarrier()) {
         report("MBB exits via unconditional branch but doesn't end with a "
                "barrier instruction!", MBB);
-      } else if (!MBB->back().isTerminator()) {
+      } else if (!getBundleStart(&MBB->back())->isTerminator()) {
         report("MBB exits via unconditional branch but the branch isn't a "
                "terminator instruction!", MBB);
       }
@@ -520,10 +520,10 @@ MachineVerifier::visitMachineBasicBlockBefore(const MachineBasicBlock *MBB) {
       if (MBB->empty()) {
         report("MBB exits via conditional branch/fall-through but doesn't "
                "contain any instructions!", MBB);
-      } else if (MBB->back().isBarrier()) {
+      } else if (getBundleStart(&MBB->back())->isBarrier()) {
         report("MBB exits via conditional branch/fall-through but ends with a "
                "barrier instruction!", MBB);
-      } else if (!MBB->back().isTerminator()) {
+      } else if (!getBundleStart(&MBB->back())->isTerminator()) {
         report("MBB exits via conditional branch/fall-through but the branch "
                "isn't a terminator instruction!", MBB);
       }
@@ -540,10 +540,10 @@ MachineVerifier::visitMachineBasicBlockBefore(const MachineBasicBlock *MBB) {
       if (MBB->empty()) {
         report("MBB exits via conditional branch/branch but doesn't "
                "contain any instructions!", MBB);
-      } else if (!MBB->back().isBarrier()) {
+      } else if (!getBundleStart(&MBB->back())->isBarrier()) {
         report("MBB exits via conditional branch/branch but doesn't end with a "
                "barrier instruction!", MBB);
-      } else if (!MBB->back().isTerminator()) {
+      } else if (!getBundleStart(&MBB->back())->isTerminator()) {
         report("MBB exits via conditional branch/branch but the branch "
                "isn't a terminator instruction!", MBB);
       }
diff --git a/test/CodeGen/Mips/machineverifier.ll b/test/CodeGen/Mips/machineverifier.ll
new file mode 100644
index 00000000000..c673fe557e6
--- /dev/null
+++ b/test/CodeGen/Mips/machineverifier.ll
@@ -0,0 +1,21 @@
+; RUN: llc < %s -march=mipsel -verify-machineinstrs
+; Make sure machine verifier understands the last instruction of a basic block
+; is not the terminator instruction after delay slot filler pass is run.
+
+@g = external global i32
+
+define void @foo() nounwind {
+entry:
+  %0 = load i32* @g, align 4
+  %tobool = icmp eq i32 %0, 0
+  br i1 %tobool, label %if.end, label %if.then
+
+if.then:                                          ; preds = %entry
+  %add = add nsw i32 %0, 10
+  store i32 %add, i32* @g, align 4
+  br label %if.end
+
+if.end:                                           ; preds = %entry, %if.then
+  ret void
+}
+