xref: /freebsd-10.2-release/contrib/llvm/patches/patch-r275633-llvm-r223171-fix-vectorizer.diff

Pull in r223170 from upstream llvm trunk (by Michael Zolotukhin):

  Apply loop-rotate to several vectorizer tests.

  Such loops shouldn't be vectorized due to the loops form.
  After applying loop-rotate (+simplifycfg) the tests again start to check
  what they are intended to check.

Pull in r223171 from upstream llvm trunk (by Michael Zolotukhin):

  PR21302. Vectorize only bottom-tested loops.

  rdar://problem/18886083

This fixes a bug in the llvm vectorizer, which could sometimes cause
vectorized loops to perform an additional iteration, leading to possible
buffer overruns.  Symptoms of this, which are usually segfaults, were
first noticed when building gcc ports, here:

https://lists.freebsd.org/pipermail/freebsd-ports/2014-September/095466.html
https://lists.freebsd.org/pipermail/freebsd-toolchain/2014-September/001211.html

Introduced here: http://svnweb.freebsd.org/changeset/base/275633

Index: lib/Transforms/Vectorize/LoopVectorize.cpp
===================================================================
--- lib/Transforms/Vectorize/LoopVectorize.cpp
+++ lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -2864,6 +2864,14 @@ bool LoopVectorizationLegality::canVectorize() {
   if (!TheLoop->getExitingBlock())
     return false;
 
+  // We only handle bottom-tested loops, i.e. loop in which the condition is
+  // checked at the end of each iteration. With that we can assume that all
+  // instructions in the loop are executed the same number of times.
+  if (TheLoop->getExitingBlock() != TheLoop->getLoopLatch()) {
+    DEBUG(dbgs() << "LV: loop control flow is not understood by vectorizer\n");
+    return false;
+  }
+
   // We need to have a loop header.
   DEBUG(dbgs() << "LV: Found a loop: " <<
         TheLoop->getHeader()->getName() << '\n');
Index: test/Transforms/LoopVectorize/loop-form.ll
===================================================================
--- test/Transforms/LoopVectorize/loop-form.ll
+++ test/Transforms/LoopVectorize/loop-form.ll
@@ -0,0 +1,31 @@
+; RUN: opt -S -loop-vectorize < %s | FileCheck %s
+target datalayout = "e-i64:64-f80:128-n8:16:32:64-S128"
+
+; Check that we vectorize only bottom-tested loops.
+; This is a reduced testcase from PR21302.
+;
+; rdar://problem/18886083
+
+%struct.X = type { i32, i16 }
+; CHECK-LABEL: @foo(
+; CHECK-NOT: vector.body
+
+define void @foo(i32 %n) {
+entry:
+  br label %for.cond
+
+for.cond:
+  %i = phi i32 [ 0, %entry ], [ %inc, %for.body ]
+  %cmp = icmp slt i32 %i, %n
+  br i1 %cmp, label %for.body, label %if.end
+
+for.body:
+  %iprom = sext i32 %i to i64
+  %b = getelementptr inbounds %struct.X* undef, i64 %iprom, i32 1
+  store i16 0, i16* %b, align 4
+  %inc = add nsw i32 %i, 1
+  br label %for.cond
+
+if.end:
+  ret void
+}
Index: test/Transforms/LoopVectorize/runtime-check-address-space.ll
===================================================================
--- test/Transforms/LoopVectorize/runtime-check-address-space.ll
+++ test/Transforms/LoopVectorize/runtime-check-address-space.ll
@@ -31,25 +31,23 @@ define void @foo(i32 addrspace(1)* %a, i32 addrspa
 ; CHECK: ret
 
 entry:
-  br label %for.cond
+  %cmp1 = icmp slt i32 0, %n
+  br i1 %cmp1, label %for.body, label %for.end
 
-for.cond:                                         ; preds = %for.body, %entry
-  %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
-  %cmp = icmp slt i32 %i.0, %n
-  br i1 %cmp, label %for.body, label %for.end
-
-for.body:                                         ; preds = %for.cond
-  %idxprom = sext i32 %i.0 to i64
+for.body:                                         ; preds = %entry, %for.body
+  %i.02 = phi i32 [ %inc, %for.body ], [ 0, %entry ]
+  %idxprom = sext i32 %i.02 to i64
   %arrayidx = getelementptr inbounds i32 addrspace(1)* %b, i64 %idxprom
   %0 = load i32 addrspace(1)* %arrayidx, align 4
   %mul = mul nsw i32 %0, 3
-  %idxprom1 = sext i32 %i.0 to i64
+  %idxprom1 = sext i32 %i.02 to i64
   %arrayidx2 = getelementptr inbounds i32 addrspace(1)* %a, i64 %idxprom1
   store i32 %mul, i32 addrspace(1)* %arrayidx2, align 4
-  %inc = add nsw i32 %i.0, 1
-  br label %for.cond
+  %inc = add nsw i32 %i.02, 1
+  %cmp = icmp slt i32 %inc, %n
+  br i1 %cmp, label %for.body, label %for.end
 
-for.end:                                          ; preds = %for.cond
+for.end:                                          ; preds = %for.body, %entry
   ret void
 }
 
@@ -60,25 +58,23 @@ define void @bar0(i32* %a, i32 addrspace(1)* %b, i
 ; CHECK: ret
 
 entry:
-  br label %for.cond
+  %cmp1 = icmp slt i32 0, %n
+  br i1 %cmp1, label %for.body, label %for.end
 
-for.cond:                                         ; preds = %for.body, %entry
-  %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
-  %cmp = icmp slt i32 %i.0, %n
-  br i1 %cmp, label %for.body, label %for.end
-
-for.body:                                         ; preds = %for.cond
-  %idxprom = sext i32 %i.0 to i64
+for.body:                                         ; preds = %entry, %for.body
+  %i.02 = phi i32 [ %inc, %for.body ], [ 0, %entry ]
+  %idxprom = sext i32 %i.02 to i64
   %arrayidx = getelementptr inbounds i32 addrspace(1)* %b, i64 %idxprom
   %0 = load i32 addrspace(1)* %arrayidx, align 4
   %mul = mul nsw i32 %0, 3
-  %idxprom1 = sext i32 %i.0 to i64
+  %idxprom1 = sext i32 %i.02 to i64
   %arrayidx2 = getelementptr inbounds i32* %a, i64 %idxprom1
   store i32 %mul, i32* %arrayidx2, align 4
-  %inc = add nsw i32 %i.0, 1
-  br label %for.cond
+  %inc = add nsw i32 %i.02, 1
+  %cmp = icmp slt i32 %inc, %n
+  br i1 %cmp, label %for.body, label %for.end
 
-for.end:                                          ; preds = %for.cond
+for.end:                                          ; preds = %for.body, %entry
   ret void
 }
 
@@ -89,25 +85,23 @@ define void @bar1(i32 addrspace(1)* %a, i32* %b, i
 ; CHECK: ret
 
 entry:
-  br label %for.cond
+  %cmp1 = icmp slt i32 0, %n
+  br i1 %cmp1, label %for.body, label %for.end
 
-for.cond:                                         ; preds = %for.body, %entry
-  %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
-  %cmp = icmp slt i32 %i.0, %n
-  br i1 %cmp, label %for.body, label %for.end
-
-for.body:                                         ; preds = %for.cond
-  %idxprom = sext i32 %i.0 to i64
+for.body:                                         ; preds = %entry, %for.body
+  %i.02 = phi i32 [ %inc, %for.body ], [ 0, %entry ]
+  %idxprom = sext i32 %i.02 to i64
   %arrayidx = getelementptr inbounds i32* %b, i64 %idxprom
   %0 = load i32* %arrayidx, align 4
   %mul = mul nsw i32 %0, 3
-  %idxprom1 = sext i32 %i.0 to i64
+  %idxprom1 = sext i32 %i.02 to i64
   %arrayidx2 = getelementptr inbounds i32 addrspace(1)* %a, i64 %idxprom1
   store i32 %mul, i32 addrspace(1)* %arrayidx2, align 4
-  %inc = add nsw i32 %i.0, 1
-  br label %for.cond
+  %inc = add nsw i32 %i.02, 1
+  %cmp = icmp slt i32 %inc, %n
+  br i1 %cmp, label %for.body, label %for.end
 
-for.end:                                          ; preds = %for.cond
+for.end:                                          ; preds = %for.body, %entry
   ret void
 }
 
@@ -119,25 +113,23 @@ define void @bar2(i32* noalias %a, i32 addrspace(1
 ; CHECK: ret
 
 entry:
-  br label %for.cond
+  %cmp1 = icmp slt i32 0, %n
+  br i1 %cmp1, label %for.body, label %for.end
 
-for.cond:                                         ; preds = %for.body, %entry
-  %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
-  %cmp = icmp slt i32 %i.0, %n
-  br i1 %cmp, label %for.body, label %for.end
-
-for.body:                                         ; preds = %for.cond
-  %idxprom = sext i32 %i.0 to i64
+for.body:                                         ; preds = %entry, %for.body
+  %i.02 = phi i32 [ %inc, %for.body ], [ 0, %entry ]
+  %idxprom = sext i32 %i.02 to i64
   %arrayidx = getelementptr inbounds i32 addrspace(1)* %b, i64 %idxprom
   %0 = load i32 addrspace(1)* %arrayidx, align 4
   %mul = mul nsw i32 %0, 3
-  %idxprom1 = sext i32 %i.0 to i64
+  %idxprom1 = sext i32 %i.02 to i64
   %arrayidx2 = getelementptr inbounds i32* %a, i64 %idxprom1
   store i32 %mul, i32* %arrayidx2, align 4
-  %inc = add nsw i32 %i.0, 1
-  br label %for.cond
+  %inc = add nsw i32 %i.02, 1
+  %cmp = icmp slt i32 %inc, %n
+  br i1 %cmp, label %for.body, label %for.end
 
-for.end:                                          ; preds = %for.cond
+for.end:                                          ; preds = %for.body, %entry
   ret void
 }
 
@@ -149,25 +141,23 @@ define void @arst0(i32* %b, i32 %n) #0 {
 ; CHECK: ret
 
 entry:
-  br label %for.cond
+  %cmp1 = icmp slt i32 0, %n
+  br i1 %cmp1, label %for.body, label %for.end
 
-for.cond:                                         ; preds = %for.body, %entry
-  %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
-  %cmp = icmp slt i32 %i.0, %n
-  br i1 %cmp, label %for.body, label %for.end
-
-for.body:                                         ; preds = %for.cond
-  %idxprom = sext i32 %i.0 to i64
+for.body:                                         ; preds = %entry, %for.body
+  %i.02 = phi i32 [ %inc, %for.body ], [ 0, %entry ]
+  %idxprom = sext i32 %i.02 to i64
   %arrayidx = getelementptr inbounds i32* %b, i64 %idxprom
   %0 = load i32* %arrayidx, align 4
   %mul = mul nsw i32 %0, 3
-  %idxprom1 = sext i32 %i.0 to i64
+  %idxprom1 = sext i32 %i.02 to i64
   %arrayidx2 = getelementptr inbounds [1024 x i32] addrspace(1)* @g_as1, i64 0, i64 %idxprom1
   store i32 %mul, i32 addrspace(1)* %arrayidx2, align 4
-  %inc = add nsw i32 %i.0, 1
-  br label %for.cond
+  %inc = add nsw i32 %i.02, 1
+  %cmp = icmp slt i32 %inc, %n
+  br i1 %cmp, label %for.body, label %for.end
 
-for.end:                                          ; preds = %for.cond
+for.end:                                          ; preds = %for.body, %entry
   ret void
 }
 
@@ -180,25 +170,23 @@ define void @arst1(i32* %b, i32 %n) #0 {
 ; CHECK: ret
 
 entry:
-  br label %for.cond
+  %cmp1 = icmp slt i32 0, %n
+  br i1 %cmp1, label %for.body, label %for.end
 
-for.cond:                                         ; preds = %for.body, %entry
-  %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
-  %cmp = icmp slt i32 %i.0, %n
-  br i1 %cmp, label %for.body, label %for.end
-
-for.body:                                         ; preds = %for.cond
-  %idxprom = sext i32 %i.0 to i64
+for.body:                                         ; preds = %entry, %for.body
+  %i.02 = phi i32 [ %inc, %for.body ], [ 0, %entry ]
+  %idxprom = sext i32 %i.02 to i64
   %arrayidx = getelementptr inbounds [1024 x i32] addrspace(1)* @g_as1, i64 0, i64 %idxprom
   %0 = load i32 addrspace(1)* %arrayidx, align 4
   %mul = mul nsw i32 %0, 3
-  %idxprom1 = sext i32 %i.0 to i64
+  %idxprom1 = sext i32 %i.02 to i64
   %arrayidx2 = getelementptr inbounds i32* %b, i64 %idxprom1
   store i32 %mul, i32* %arrayidx2, align 4
-  %inc = add nsw i32 %i.0, 1
-  br label %for.cond
+  %inc = add nsw i32 %i.02, 1
+  %cmp = icmp slt i32 %inc, %n
+  br i1 %cmp, label %for.body, label %for.end
 
-for.end:                                          ; preds = %for.cond
+for.end:                                          ; preds = %for.body, %entry
   ret void
 }
 
@@ -210,25 +198,23 @@ define void @aoeu(i32 %n) #0 {
 ; CHECK: ret
 
 entry:
-  br label %for.cond
+  %cmp1 = icmp slt i32 0, %n
+  br i1 %cmp1, label %for.body, label %for.end
 
-for.cond:                                         ; preds = %for.body, %entry
-  %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
-  %cmp = icmp slt i32 %i.0, %n
-  br i1 %cmp, label %for.body, label %for.end
-
-for.body:                                         ; preds = %for.cond
-  %idxprom = sext i32 %i.0 to i64
+for.body:                                         ; preds = %entry, %for.body
+  %i.02 = phi i32 [ %inc, %for.body ], [ 0, %entry ]
+  %idxprom = sext i32 %i.02 to i64
   %arrayidx = getelementptr inbounds [1024 x i32] addrspace(2)* @q_as2, i64 0, i64 %idxprom
   %0 = load i32 addrspace(2)* %arrayidx, align 4
   %mul = mul nsw i32 %0, 3
-  %idxprom1 = sext i32 %i.0 to i64
+  %idxprom1 = sext i32 %i.02 to i64
   %arrayidx2 = getelementptr inbounds [1024 x i32] addrspace(1)* @g_as1, i64 0, i64 %idxprom1
   store i32 %mul, i32 addrspace(1)* %arrayidx2, align 4
-  %inc = add nsw i32 %i.0, 1
-  br label %for.cond
+  %inc = add nsw i32 %i.02, 1
+  %cmp = icmp slt i32 %inc, %n
+  br i1 %cmp, label %for.body, label %for.end
 
-for.end:                                          ; preds = %for.cond
+for.end:                                          ; preds = %for.body, %entry
   ret void
 }
 
Index: test/Transforms/LoopVectorize/runtime-check-readonly-address-space.ll
===================================================================
--- test/Transforms/LoopVectorize/runtime-check-readonly-address-space.ll
+++ test/Transforms/LoopVectorize/runtime-check-readonly-address-space.ll
@@ -8,26 +8,24 @@ define void @add_ints_1_1_1(i32 addrspace(1)* %a,
 ; CHECK-LABEL: @add_ints_1_1_1(
 ; CHECK: <4 x i32>
 ; CHECK: ret
+
 entry:
-  br label %for.cond
+  br label %for.body
 
-for.cond:                                         ; preds = %for.body, %entry
-  %i.0 = phi i64 [ 0, %entry ], [ %inc, %for.body ]
-  %cmp = icmp ult i64 %i.0, 200
-  br i1 %cmp, label %for.body, label %for.end
-
-for.body:                                         ; preds = %for.cond
-  %arrayidx = getelementptr inbounds i32 addrspace(1)* %b, i64 %i.0
+for.body:                                         ; preds = %entry, %for.body
+  %i.01 = phi i64 [ 0, %entry ], [ %inc, %for.body ]
+  %arrayidx = getelementptr inbounds i32 addrspace(1)* %b, i64 %i.01
   %0 = load i32 addrspace(1)* %arrayidx, align 4
-  %arrayidx1 = getelementptr inbounds i32 addrspace(1)* %c, i64 %i.0
+  %arrayidx1 = getelementptr inbounds i32 addrspace(1)* %c, i64 %i.01
   %1 = load i32 addrspace(1)* %arrayidx1, align 4
   %add = add nsw i32 %0, %1
-  %arrayidx2 = getelementptr inbounds i32 addrspace(1)* %a, i64 %i.0
+  %arrayidx2 = getelementptr inbounds i32 addrspace(1)* %a, i64 %i.01
   store i32 %add, i32 addrspace(1)* %arrayidx2, align 4
-  %inc = add i64 %i.0, 1
-  br label %for.cond
+  %inc = add i64 %i.01, 1
+  %cmp = icmp ult i64 %inc, 200
+  br i1 %cmp, label %for.body, label %for.end
 
-for.end:                                          ; preds = %for.cond
+for.end:                                          ; preds = %for.body
   ret void
 }
 
@@ -35,26 +33,24 @@ define void @add_ints_as_1_0_0(i32 addrspace(1)* %
 ; CHECK-LABEL: @add_ints_as_1_0_0(
 ; CHECK-NOT: <4 x i32>
 ; CHECK: ret
+
 entry:
-  br label %for.cond
+  br label %for.body
 
-for.cond:                                         ; preds = %for.body, %entry
-  %i.0 = phi i64 [ 0, %entry ], [ %inc, %for.body ]
-  %cmp = icmp ult i64 %i.0, 200
-  br i1 %cmp, label %for.body, label %for.end
-
-for.body:                                         ; preds = %for.cond
-  %arrayidx = getelementptr inbounds i32* %b, i64 %i.0
+for.body:                                         ; preds = %entry, %for.body
+  %i.01 = phi i64 [ 0, %entry ], [ %inc, %for.body ]
+  %arrayidx = getelementptr inbounds i32* %b, i64 %i.01
   %0 = load i32* %arrayidx, align 4
-  %arrayidx1 = getelementptr inbounds i32* %c, i64 %i.0
+  %arrayidx1 = getelementptr inbounds i32* %c, i64 %i.01
   %1 = load i32* %arrayidx1, align 4
   %add = add nsw i32 %0, %1
-  %arrayidx2 = getelementptr inbounds i32 addrspace(1)* %a, i64 %i.0
+  %arrayidx2 = getelementptr inbounds i32 addrspace(1)* %a, i64 %i.01
   store i32 %add, i32 addrspace(1)* %arrayidx2, align 4
-  %inc = add i64 %i.0, 1
-  br label %for.cond
+  %inc = add i64 %i.01, 1
+  %cmp = icmp ult i64 %inc, 200
+  br i1 %cmp, label %for.body, label %for.end
 
-for.end:                                          ; preds = %for.cond
+for.end:                                          ; preds = %for.body
   ret void
 }
 
@@ -62,26 +58,24 @@ define void @add_ints_as_0_1_0(i32* %a, i32 addrsp
 ; CHECK-LABEL: @add_ints_as_0_1_0(
 ; CHECK-NOT: <4 x i32>
 ; CHECK: ret
+
 entry:
-  br label %for.cond
+  br label %for.body
 
-for.cond:                                         ; preds = %for.body, %entry
-  %i.0 = phi i64 [ 0, %entry ], [ %inc, %for.body ]
-  %cmp = icmp ult i64 %i.0, 200
-  br i1 %cmp, label %for.body, label %for.end
-
-for.body:                                         ; preds = %for.cond
-  %arrayidx = getelementptr inbounds i32 addrspace(1)* %b, i64 %i.0
+for.body:                                         ; preds = %entry, %for.body
+  %i.01 = phi i64 [ 0, %entry ], [ %inc, %for.body ]
+  %arrayidx = getelementptr inbounds i32 addrspace(1)* %b, i64 %i.01
   %0 = load i32 addrspace(1)* %arrayidx, align 4
-  %arrayidx1 = getelementptr inbounds i32* %c, i64 %i.0
+  %arrayidx1 = getelementptr inbounds i32* %c, i64 %i.01
   %1 = load i32* %arrayidx1, align 4
   %add = add nsw i32 %0, %1
-  %arrayidx2 = getelementptr inbounds i32* %a, i64 %i.0
+  %arrayidx2 = getelementptr inbounds i32* %a, i64 %i.01
   store i32 %add, i32* %arrayidx2, align 4
-  %inc = add i64 %i.0, 1
-  br label %for.cond
+  %inc = add i64 %i.01, 1
+  %cmp = icmp ult i64 %inc, 200
+  br i1 %cmp, label %for.body, label %for.end
 
-for.end:                                          ; preds = %for.cond
+for.end:                                          ; preds = %for.body
   ret void
 }
 
@@ -89,26 +83,24 @@ define void @add_ints_as_0_1_1(i32* %a, i32 addrsp
 ; CHECK-LABEL: @add_ints_as_0_1_1(
 ; CHECK-NOT: <4 x i32>
 ; CHECK: ret
+
 entry:
-  br label %for.cond
+  br label %for.body
 
-for.cond:                                         ; preds = %for.body, %entry
-  %i.0 = phi i64 [ 0, %entry ], [ %inc, %for.body ]
-  %cmp = icmp ult i64 %i.0, 200
-  br i1 %cmp, label %for.body, label %for.end
-
-for.body:                                         ; preds = %for.cond
-  %arrayidx = getelementptr inbounds i32 addrspace(1)* %b, i64 %i.0
+for.body:                                         ; preds = %entry, %for.body
+  %i.01 = phi i64 [ 0, %entry ], [ %inc, %for.body ]
+  %arrayidx = getelementptr inbounds i32 addrspace(1)* %b, i64 %i.01
   %0 = load i32 addrspace(1)* %arrayidx, align 4
-  %arrayidx1 = getelementptr inbounds i32 addrspace(1)* %c, i64 %i.0
+  %arrayidx1 = getelementptr inbounds i32 addrspace(1)* %c, i64 %i.01
   %1 = load i32 addrspace(1)* %arrayidx1, align 4
   %add = add nsw i32 %0, %1
-  %arrayidx2 = getelementptr inbounds i32* %a, i64 %i.0
+  %arrayidx2 = getelementptr inbounds i32* %a, i64 %i.01
   store i32 %add, i32* %arrayidx2, align 4
-  %inc = add i64 %i.0, 1
-  br label %for.cond
+  %inc = add i64 %i.01, 1
+  %cmp = icmp ult i64 %inc, 200
+  br i1 %cmp, label %for.body, label %for.end
 
-for.end:                                          ; preds = %for.cond
+for.end:                                          ; preds = %for.body
   ret void
 }
 
@@ -116,26 +108,24 @@ define void @add_ints_as_0_1_2(i32* %a, i32 addrsp
 ; CHECK-LABEL: @add_ints_as_0_1_2(
 ; CHECK-NOT: <4 x i32>
 ; CHECK: ret
+
 entry:
-  br label %for.cond
+  br label %for.body
 
-for.cond:                                         ; preds = %for.body, %entry
-  %i.0 = phi i64 [ 0, %entry ], [ %inc, %for.body ]
-  %cmp = icmp ult i64 %i.0, 200
-  br i1 %cmp, label %for.body, label %for.end
-
-for.body:                                         ; preds = %for.cond
-  %arrayidx = getelementptr inbounds i32 addrspace(1)* %b, i64 %i.0
+for.body:                                         ; preds = %entry, %for.body
+  %i.01 = phi i64 [ 0, %entry ], [ %inc, %for.body ]
+  %arrayidx = getelementptr inbounds i32 addrspace(1)* %b, i64 %i.01
   %0 = load i32 addrspace(1)* %arrayidx, align 4
-  %arrayidx1 = getelementptr inbounds i32 addrspace(2)* %c, i64 %i.0
+  %arrayidx1 = getelementptr inbounds i32 addrspace(2)* %c, i64 %i.01
   %1 = load i32 addrspace(2)* %arrayidx1, align 4
   %add = add nsw i32 %0, %1
-  %arrayidx2 = getelementptr inbounds i32* %a, i64 %i.0
+  %arrayidx2 = getelementptr inbounds i32* %a, i64 %i.01
   store i32 %add, i32* %arrayidx2, align 4
-  %inc = add i64 %i.0, 1
-  br label %for.cond
+  %inc = add i64 %i.01, 1
+  %cmp = icmp ult i64 %inc, 200
+  br i1 %cmp, label %for.body, label %for.end
 
-for.end:                                          ; preds = %for.cond
+for.end:                                          ; preds = %for.body
   ret void
 }