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      1 ; RUN: opt -S -o - -basicaa -domtree -gvn %s | FileCheck %s
      2 
      3 target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
      4 
      5 %struct.S1 = type { i32, i32 }
      6 
      7 @a2 = common global i32* null, align 8
      8 @a = common global i32* null, align 8
      9 @s1 = common global %struct.S1 zeroinitializer, align 8
     10 
     11 ; Check that GVN doesn't determine %2 is partially redundant.
     12 
     13 ; CHECK-LABEL: define i32 @volatile_load
     14 ; CHECK: for.body:
     15 ; CHECK: %2 = load i32*
     16 ; CHECK: %3 = load volatile i32*
     17 ; CHECK: for.cond.for.end_crit_edge:
     18 
     19 define i32 @volatile_load(i32 %n) {
     20 entry:
     21   %cmp6 = icmp sgt i32 %n, 0
     22   br i1 %cmp6, label %for.body.lr.ph, label %for.end
     23 
     24 for.body.lr.ph:
     25   %0 = load i32** @a2, align 8, !tbaa !1
     26   %1 = load i32** @a, align 8, !tbaa !1
     27   br label %for.body
     28 
     29 for.body:
     30   %indvars.iv = phi i64 [ 0, %for.body.lr.ph ], [ %indvars.iv.next, %for.body ]
     31   %s.09 = phi i32 [ 0, %for.body.lr.ph ], [ %add, %for.body ]
     32   %p.08 = phi i32* [ %0, %for.body.lr.ph ], [ %incdec.ptr, %for.body ]
     33   %2 = load i32* %p.08, align 4, !tbaa !5
     34   %arrayidx = getelementptr inbounds i32* %1, i64 %indvars.iv
     35   store i32 %2, i32* %arrayidx, align 4, !tbaa !5
     36   %3 = load volatile i32* %p.08, align 4, !tbaa !5
     37   %add = add nsw i32 %3, %s.09
     38   %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
     39   %incdec.ptr = getelementptr inbounds i32* %p.08, i64 1
     40   %lftr.wideiv = trunc i64 %indvars.iv.next to i32
     41   %exitcond = icmp ne i32 %lftr.wideiv, %n
     42   br i1 %exitcond, label %for.body, label %for.cond.for.end_crit_edge
     43 
     44 for.cond.for.end_crit_edge:
     45   %add.lcssa = phi i32 [ %add, %for.body ]
     46   br label %for.end
     47 
     48 for.end:
     49   %s.0.lcssa = phi i32 [ %add.lcssa, %for.cond.for.end_crit_edge ], [ 0, %entry ]
     50   ret i32 %s.0.lcssa
     51 }
     52 
     53 ; %1 is partially redundant if %0 can be widened to a 64-bit load.
     54 
     55 ; CHECK-LABEL: define i32 @overaligned_load
     56 ; CHECK: if.end:
     57 ; CHECK-NOT: %1 = load i32*
     58 
     59 define i32 @overaligned_load(i32 %a, i32* nocapture %b) {
     60 entry:
     61   %cmp = icmp sgt i32 %a, 0
     62   br i1 %cmp, label %if.then, label %if.else
     63 
     64 if.then:
     65   %0 = load i32* getelementptr inbounds (%struct.S1* @s1, i64 0, i32 0), align 8, !tbaa !5
     66   br label %if.end
     67 
     68 if.else:
     69   %arrayidx = getelementptr inbounds i32* %b, i64 2
     70   store i32 10, i32* %arrayidx, align 4, !tbaa !5
     71   br label %if.end
     72 
     73 if.end:
     74   %i.0 = phi i32 [ %0, %if.then ], [ 0, %if.else ]
     75   %p.0 = phi i32* [ getelementptr inbounds (%struct.S1* @s1, i64 0, i32 0), %if.then ], [ %b, %if.else ]
     76   %add.ptr = getelementptr inbounds i32* %p.0, i64 1
     77   %1 = load i32* %add.ptr, align 4, !tbaa !5
     78   %add1 = add nsw i32 %1, %i.0
     79   ret i32 %add1
     80 }
     81 
     82 !1 = metadata !{metadata !2, metadata !2, i64 0}
     83 !2 = metadata !{metadata !"any pointer", metadata !3, i64 0}
     84 !3 = metadata !{metadata !"omnipotent char", metadata !4, i64 0}
     85 !4 = metadata !{metadata !"Simple C/C++ TBAA"}
     86 !5 = metadata !{metadata !6, metadata !6, i64 0}
     87 !6 = metadata !{metadata !"int", metadata !3, i64 0}
     88