Revert r251492 "[IndVarSimplify] Rewrite loop exit values with their

[oota-llvm.git] / test / Transforms / LoopUnroll / scevunroll.ll

diff --git a/test/Transforms/LoopUnroll/scevunroll.ll b/test/Transforms/LoopUnroll/scevunroll.ll
index 9971f310ec452b75ab9f2250bf322a9c9231235e..a5c9a6efacf38fdcad66c97144ff5ff3040e2b32 100644 (file)
--- a/test/Transforms/LoopUnroll/scevunroll.ll
+++ b/test/Transforms/LoopUnroll/scevunroll.ll
@@ -7,7 +7,7 @@
 
 ; Completely unroll loops without a canonical IV.
 ;
-; CHECK: @sansCanonical
+; CHECK-LABEL: @sansCanonical(
 ; CHECK-NOT: phi
 ; CHECK-NOT: icmp
 ; CHECK: ret
@@ -19,8 +19,8 @@ while.body:
   %iv = phi i64 [ 10, %entry ], [ %iv.next, %while.body ]
   %sum = phi i32 [ 0, %entry ], [ %sum.next, %while.body ]
   %iv.next = add i64 %iv, -1
-  %adr = getelementptr inbounds i32* %base, i64 %iv.next
-  %tmp = load i32* %adr, align 8
+  %adr = getelementptr inbounds i32, i32* %base, i64 %iv.next
+  %tmp = load i32, i32* %adr, align 8
   %sum.next = add i32 %sum, %tmp
   %iv.narrow = trunc i64 %iv.next to i32
   %cmp.i65 = icmp sgt i32 %iv.narrow, 0
@@ -35,7 +35,7 @@ exit:
 ; latch block. Canonical unrolling incorrectly unrolls it, but SCEV
 ; unrolling does not.
 ;
-; CHECK: @earlyLoopTest
+; CHECK-LABEL: @earlyLoopTest(
 ; CHECK: tail:
 ; CHECK-NOT: br
 ; CHECK: br i1 %cmp2, label %loop, label %exit2
@@ -46,8 +46,8 @@ entry:
 loop:
   %iv = phi i64 [ 0, %entry ], [ %inc, %tail ]
   %s = phi i64 [ 0, %entry ], [ %s.next, %tail ]
-  %adr = getelementptr i64* %base, i64 %iv
-  %val = load i64* %adr
+  %adr = getelementptr i64, i64* %base, i64 %iv
+  %val = load i64, i64* %adr
   %s.next = add i64 %s, %val
   %inc = add i64 %iv, 1
   %cmp = icmp ne i64 %inc, 4
@@ -66,9 +66,9 @@ exit2:
 
 ; SCEV properly unrolls multi-exit loops.
 ;
-; CHECK: @multiExit
-; CHECK: getelementptr i32* %base, i64 10
-; CHECK-NEXT: load i32*
+; CHECK-LABEL: @multiExit(
+; CHECK: getelementptr i32, i32* %base, i32 10
+; CHECK-NEXT: load i32, i32*
 ; CHECK: br i1 false, label %l2.10, label %exit1
 ; CHECK: l2.10:
 ; CHECK-NOT: br
@@ -81,8 +81,8 @@ l1:
   %iv2 = phi i32 [ 0, %entry ], [ %inc2, %l2 ]
   %inc1 = add i32 %iv1, 1
   %inc2 = add i32 %iv2, 1
-  %adr = getelementptr i32* %base, i32 %iv1
-  %val = load i32* %adr
+  %adr = getelementptr i32, i32* %base, i32 %iv1
+  %val = load i32, i32* %adr
   %cmp1 = icmp slt i32 %iv1, 5
   br i1 %cmp1, label %l2, label %exit1
 l2:
@@ -100,7 +100,7 @@ exit2:
 ; LoopUnroll utility uses this assumption to optimize the latch
 ; block's branch.
 ;
-; CHECK: @multiExit
+; CHECK-LABEL: @multiExitIncomplete(
 ; CHECK: l3:
 ; CHECK-NOT: br
 ; CHECK:   br i1 %cmp3, label %l1, label %exit3
@@ -112,8 +112,8 @@ l1:
   %iv2 = phi i32 [ 0, %entry ], [ %inc2, %l3 ]
   %inc1 = add i32 %iv1, 1
   %inc2 = add i32 %iv2, 1
-  %adr = getelementptr i32* %base, i32 %iv1
-  %val = load i32* %adr
+  %adr = getelementptr i32, i32* %base, i32 %iv1
+  %val = load i32, i32* %adr
   %cmp1 = icmp slt i32 %iv1, 5
   br i1 %cmp1, label %l2, label %exit1
 l2:
@@ -134,7 +134,7 @@ exit3:
 ; When loop unroll merges a loop exit with one of its parent loop's
 ; exits, SCEV must forget its ExitNotTaken info.
 ;
-; CHECK: @nestedUnroll
+; CHECK-LABEL: @nestedUnroll(
 ; CHECK-NOT: br i1
 ; CHECK: for.body87:
 define void @nestedUnroll() nounwind {
@@ -170,3 +170,38 @@ for.body87:
   br label %for.body87
 }
 
+; PR16130: clang produces incorrect code with loop/expression at -O2
+; rdar:14036816 loop-unroll makes assumptions about undefined behavior
+;
+; The loop latch is assumed to exit after the first iteration because
+; of the induction variable's NSW flag. However, the loop latch's
+; equality test is skipped and the loop exits after the second
+; iteration via the early exit. So loop unrolling cannot assume that
+; the loop latch's exit count of zero is an upper bound on the number
+; of iterations.
+;
+; CHECK-LABEL: @nsw_latch(
+; CHECK: for.body:
+; CHECK: %b.03 = phi i32 [ 0, %entry ], [ %add, %for.cond ]
+; CHECK: return:
+; CHECK: %b.03.lcssa = phi i32 [ %b.03, %for.body ], [ %b.03, %for.cond ]
+define void @nsw_latch(i32* %a) nounwind {
+entry:
+  br label %for.body
+
+for.body:                                         ; preds = %for.cond, %entry
+  %b.03 = phi i32 [ 0, %entry ], [ %add, %for.cond ]
+  %tobool = icmp eq i32 %b.03, 0
+  %add = add nsw i32 %b.03, 8
+  br i1 %tobool, label %for.cond, label %return
+
+for.cond:                                         ; preds = %for.body
+  %cmp = icmp eq i32 %add, 13
+  br i1 %cmp, label %return, label %for.body
+
+return:                                           ; preds = %for.body, %for.cond
+  %b.03.lcssa = phi i32 [ %b.03, %for.body ], [ %b.03, %for.cond ]
+  %retval.0 = phi i32 [ 1, %for.body ], [ 0, %for.cond ]
+  store i32 %b.03.lcssa, i32* %a, align 4
+  ret void
+}