289 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			289 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			LLVM
		
	
	
	
| ; RUN: opt -loop-accesses -analyze < %s | FileCheck %s
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| ; RUN: opt -passes='require<scalar-evolution>,require<aa>,loop(print-access-info)' -disable-output  < %s 2>&1 | FileCheck %s
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| 
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| target datalayout = "e-m:e-i64:64-i128:128-n32:64-S128"
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| target triple = "aarch64--linux-gnueabi"
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| 
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| ; 3 reads and 3 writes should need 12 memchecks
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| ; CHECK: function 'testf':
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| ; CHECK: Memory dependences are safe with run-time checks
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| 
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| ; Memory dependencies have labels starting from 0, so in
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| ; order to verify that we have n checks, we look for
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| ; (n-1): and not n:.
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| 
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| ; CHECK: Run-time memory checks:
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| ; CHECK-NEXT: Check 0:
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| ; CHECK: Check 11:
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| ; CHECK-NOT: Check 12:
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| 
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| define void @testf(i16* %a,
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|                i16* %b,
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|                i16* %c,
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|                i16* %d,
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|                i16* %e,
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|                i16* %f) {
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| entry:
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|   br label %for.body
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| 
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| for.body:                                         ; preds = %for.body, %entry
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|   %ind = phi i64 [ 0, %entry ], [ %add, %for.body ]
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| 
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|   %add = add nuw nsw i64 %ind, 1
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| 
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|   %arrayidxA = getelementptr inbounds i16, i16* %a, i64 %ind
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|   %loadA = load i16, i16* %arrayidxA, align 2
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| 
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|   %arrayidxB = getelementptr inbounds i16, i16* %b, i64 %ind
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|   %loadB = load i16, i16* %arrayidxB, align 2
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| 
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|   %arrayidxC = getelementptr inbounds i16, i16* %c, i64 %ind
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|   %loadC = load i16, i16* %arrayidxC, align 2
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| 
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|   %mul = mul i16 %loadB, %loadA
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|   %mul1 = mul i16 %mul, %loadC
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| 
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|   %arrayidxD = getelementptr inbounds i16, i16* %d, i64 %ind
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|   store i16 %mul1, i16* %arrayidxD, align 2
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| 
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|   %arrayidxE = getelementptr inbounds i16, i16* %e, i64 %ind
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|   store i16 %mul, i16* %arrayidxE, align 2
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| 
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|   %arrayidxF = getelementptr inbounds i16, i16* %f, i64 %ind
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|   store i16 %mul1, i16* %arrayidxF, align 2
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| 
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|   %exitcond = icmp eq i64 %add, 20
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|   br i1 %exitcond, label %for.end, label %for.body
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| 
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| for.end:                                          ; preds = %for.body
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|   ret void
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| }
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| 
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| ; The following (testg and testh) check that we can group
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| ; memory checks of accesses which differ by a constant value.
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| ; Both tests are based on the following C code:
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| ;
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| ; void testh(short *a, short *b, short *c) {
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| ;   unsigned long ind = 0;
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| ;   for (unsigned long ind = 0; ind < 20; ++ind) {
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| ;     c[2 * ind] = a[ind] * a[ind + 1];
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| ;     c[2 * ind + 1] = a[ind] * a[ind + 1] * b[ind];
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| ;   }
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| ; }
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| ;
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| ; It is sufficient to check the intervals
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| ; [a, a + 21], [b, b + 20] against [c, c + 41].
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| 
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| ; 3 reads and 2 writes - two of the reads can be merged,
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| ; and the writes can be merged as well. This gives us a
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| ; total of 2 memory checks.
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| 
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| ; CHECK: function 'testg':
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| 
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| ; CHECK: Run-time memory checks:
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| ; CHECK-NEXT:   Check 0:
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| ; CHECK-NEXT:     Comparing group ([[ZERO:.+]]):
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| ; CHECK-NEXT:       %arrayidxC1 = getelementptr inbounds i16, i16* %c, i64 %store_ind_inc
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| ; CHECK-NEXT:       %arrayidxC = getelementptr inbounds i16, i16* %c, i64 %store_ind
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| ; CHECK-NEXT:     Against group ([[ONE:.+]]):
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| ; CHECK-NEXT:       %arrayidxA1 = getelementptr inbounds i16, i16* %a, i64 %add
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| ; CHECK-NEXT:       %arrayidxA = getelementptr inbounds i16, i16* %a, i64 %ind
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| ; CHECK-NEXT:   Check 1:
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| ; CHECK-NEXT:     Comparing group ({{.*}}[[ZERO]]):
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| ; CHECK-NEXT:       %arrayidxC1 = getelementptr inbounds i16, i16* %c, i64 %store_ind_inc
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| ; CHECK-NEXT:       %arrayidxC = getelementptr inbounds i16, i16* %c, i64 %store_ind
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| ; CHECK-NEXT:     Against group ([[TWO:.+]]):
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| ; CHECK-NEXT:       %arrayidxB = getelementptr inbounds i16, i16* %b, i64 %ind
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| ; CHECK-NEXT:   Grouped accesses:
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| ; CHECK-NEXT:    Group {{.*}}[[ZERO]]:
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| ; CHECK-NEXT:       (Low: %c High: (78 + %c))
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| ; CHECK-NEXT:         Member: {(2 + %c)<nsw>,+,4}
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| ; CHECK-NEXT:         Member: {%c,+,4}
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| ; CHECK-NEXT:     Group {{.*}}[[ONE]]:
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| ; CHECK-NEXT:       (Low: %a High: (40 + %a))
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| ; CHECK-NEXT:         Member: {(2 + %a)<nsw>,+,2}
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| ; CHECK-NEXT:         Member: {%a,+,2}
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| ; CHECK-NEXT:     Group {{.*}}[[TWO]]:
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| ; CHECK-NEXT:       (Low: %b High: (38 + %b))
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| ; CHECK-NEXT:         Member: {%b,+,2}
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| 
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| define void @testg(i16* %a,
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|                i16* %b,
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|                i16* %c) {
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| entry:
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|   br label %for.body
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| 
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| for.body:                                         ; preds = %for.body, %entry
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|   %ind = phi i64 [ 0, %entry ], [ %add, %for.body ]
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|   %store_ind = phi i64 [ 0, %entry ], [ %store_ind_next, %for.body ]
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| 
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|   %add = add nuw nsw i64 %ind, 1
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|   %store_ind_inc = add nuw nsw i64 %store_ind, 1
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|   %store_ind_next = add nuw nsw i64 %store_ind_inc, 1
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| 
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|   %arrayidxA = getelementptr inbounds i16, i16* %a, i64 %ind
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|   %loadA = load i16, i16* %arrayidxA, align 2
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| 
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|   %arrayidxA1 = getelementptr inbounds i16, i16* %a, i64 %add
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|   %loadA1 = load i16, i16* %arrayidxA1, align 2
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| 
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|   %arrayidxB = getelementptr inbounds i16, i16* %b, i64 %ind
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|   %loadB = load i16, i16* %arrayidxB, align 2
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| 
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|   %mul = mul i16 %loadA, %loadA1
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|   %mul1 = mul i16 %mul, %loadB
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| 
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|   %arrayidxC = getelementptr inbounds i16, i16* %c, i64 %store_ind
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|   store i16 %mul1, i16* %arrayidxC, align 2
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| 
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|   %arrayidxC1 = getelementptr inbounds i16, i16* %c, i64 %store_ind_inc
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|   store i16 %mul, i16* %arrayidxC1, align 2
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| 
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|   %exitcond = icmp eq i64 %add, 20
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|   br i1 %exitcond, label %for.end, label %for.body
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| 
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| for.end:                                          ; preds = %for.body
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|   ret void
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| }
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| 
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| ; 3 reads and 2 writes - the writes can be merged into a single
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| ; group, but the GEPs used for the reads are not marked as inbounds.
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| ; We can still merge them because we are using a unit stride for
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| ; accesses, so we cannot overflow the GEPs.
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| 
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| ; CHECK: function 'testh':
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| ; CHECK: Run-time memory checks:
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| ; CHECK-NEXT:   Check 0:
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| ; CHECK-NEXT:     Comparing group ([[ZERO:.+]]):
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| ; CHECK-NEXT:         %arrayidxC1 = getelementptr inbounds i16, i16* %c, i64 %store_ind_inc
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| ; CHECK-NEXT:         %arrayidxC = getelementptr inbounds i16, i16* %c, i64 %store_ind
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| ; CHECK-NEXT:     Against group ([[ONE:.+]]):
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| ; CHECK-NEXT:         %arrayidxA1 = getelementptr i16, i16* %a, i64 %add
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| ; CHECK-NEXT:         %arrayidxA = getelementptr i16, i16* %a, i64 %ind
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| ; CHECK-NEXT:   Check 1:
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| ; CHECK-NEXT:     Comparing group ({{.*}}[[ZERO]]):
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| ; CHECK-NEXT:         %arrayidxC1 = getelementptr inbounds i16, i16* %c, i64 %store_ind_inc
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| ; CHECK-NEXT:         %arrayidxC = getelementptr inbounds i16, i16* %c, i64 %store_ind
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| ; CHECK-NEXT:     Against group ([[TWO:.+]]):
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| ; CHECK-NEXT:         %arrayidxB = getelementptr i16, i16* %b, i64 %ind
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| ; CHECK-NEXT:   Grouped accesses:
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| ; CHECK-NEXT:     Group {{.*}}[[ZERO]]:
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| ; CHECK-NEXT:       (Low: %c High: (78 + %c))
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| ; CHECK-NEXT:         Member: {(2 + %c)<nsw>,+,4}
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| ; CHECK-NEXT:         Member: {%c,+,4}
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| ; CHECK-NEXT:     Group {{.*}}[[ONE]]:
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| ; CHECK-NEXT:       (Low: %a High: (40 + %a))
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| ; CHECK-NEXT:         Member: {(2 + %a),+,2}
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| ; CHECK-NEXT:         Member: {%a,+,2}
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| ; CHECK-NEXT:     Group {{.*}}[[TWO]]:
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| ; CHECK-NEXT:       (Low: %b High: (38 + %b))
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| ; CHECK-NEXT:         Member: {%b,+,2}
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| 
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| define void @testh(i16* %a,
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|                i16* %b,
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|                i16* %c) {
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| entry:
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|   br label %for.body
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| 
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| for.body:                                         ; preds = %for.body, %entry
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|   %ind = phi i64 [ 0, %entry ], [ %add, %for.body ]
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|   %store_ind = phi i64 [ 0, %entry ], [ %store_ind_next, %for.body ]
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| 
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|   %add = add nuw nsw i64 %ind, 1
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|   %store_ind_inc = add nuw nsw i64 %store_ind, 1
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|   %store_ind_next = add nuw nsw i64 %store_ind_inc, 1
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| 
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|   %arrayidxA = getelementptr i16, i16* %a, i64 %ind
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|   %loadA = load i16, i16* %arrayidxA, align 2
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| 
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|   %arrayidxA1 = getelementptr i16, i16* %a, i64 %add
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|   %loadA1 = load i16, i16* %arrayidxA1, align 2
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| 
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|   %arrayidxB = getelementptr i16, i16* %b, i64 %ind
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|   %loadB = load i16, i16* %arrayidxB, align 2
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| 
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|   %mul = mul i16 %loadA, %loadA1
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|   %mul1 = mul i16 %mul, %loadB
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| 
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|   %arrayidxC = getelementptr inbounds i16, i16* %c, i64 %store_ind
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|   store i16 %mul1, i16* %arrayidxC, align 2
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| 
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|   %arrayidxC1 = getelementptr inbounds i16, i16* %c, i64 %store_ind_inc
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|   store i16 %mul, i16* %arrayidxC1, align 2
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| 
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|   %exitcond = icmp eq i64 %add, 20
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|   br i1 %exitcond, label %for.end, label %for.body
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| 
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| for.end:                                          ; preds = %for.body
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|   ret void
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| }
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| 
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| ; Don't merge pointers if we need to perform a check against a pointer
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| ; to the same underlying object (doing so would emit a check that could be
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| ; falsely invalidated) For example, in the following loop:
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| ;
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| ; for (i = 0; i < 5000; ++i)
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| ;   a[i + offset] = a[i] + a[i + 10000]
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| ;
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| ; we should not merge the intervals associated with the reads (0,5000) and
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| ; (10000, 15000) into (0, 15000) as this will pottentially fail the check
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| ; against the interval associated with the write.
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| ;
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| ; We cannot have this check unless ShouldRetryWithRuntimeCheck is set,
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| ; and therefore the grouping algorithm would create a separate group for
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| ; each pointer.
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| 
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| ; CHECK: function 'testi':
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| ; CHECK: Run-time memory checks:
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| ; CHECK-NEXT:   Check 0:
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| ; CHECK-NEXT:     Comparing group ([[ZERO:.+]]):
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| ; CHECK-NEXT:       %storeidx = getelementptr inbounds i16, i16* %a, i64 %store_ind
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| ; CHECK-NEXT:     Against group ([[ONE:.+]]):
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| ; CHECK-NEXT:       %arrayidxA1 = getelementptr i16, i16* %a, i64 %ind
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| ; CHECK-NEXT:   Check 1:
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| ; CHECK-NEXT:     Comparing group ({{.*}}[[ZERO]]):
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| ; CHECK-NEXT:       %storeidx = getelementptr inbounds i16, i16* %a, i64 %store_ind
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| ; CHECK-NEXT:     Against group ([[TWO:.+]]):
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| ; CHECK-NEXT:       %arrayidxA2 = getelementptr i16, i16* %a, i64 %ind2
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| ; CHECK-NEXT:   Grouped accesses:
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| ; CHECK-NEXT:     Group {{.*}}[[ZERO]]:
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| ; CHECK-NEXT:       (Low: ((2 * %offset) + %a)<nsw> High: (9998 + (2 * %offset) + %a))
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| ; CHECK-NEXT:         Member: {((2 * %offset) + %a)<nsw>,+,2}<nsw><%for.body>
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| ; CHECK-NEXT:     Group {{.*}}[[ONE]]:
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| ; CHECK-NEXT:       (Low: %a High: (9998 + %a))
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| ; CHECK-NEXT:         Member: {%a,+,2}<%for.body>
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| ; CHECK-NEXT:     Group {{.*}}[[TWO]]:
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| ; CHECK-NEXT:       (Low: (20000 + %a) High: (29998 + %a))
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| ; CHECK-NEXT:         Member: {(20000 + %a),+,2}<%for.body>
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| 
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| define void @testi(i16* %a,
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|                    i64 %offset) {
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| entry:
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|   br label %for.body
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| 
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| for.body:                                         ; preds = %for.body, %entry
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|   %ind = phi i64 [ 0, %entry ], [ %add, %for.body ]
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|   %store_ind = phi i64 [ %offset, %entry ], [ %store_ind_inc, %for.body ]
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| 
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|   %add = add nuw nsw i64 %ind, 1
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|   %store_ind_inc = add nuw nsw i64 %store_ind, 1
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| 
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|   %arrayidxA1 = getelementptr i16, i16* %a, i64 %ind
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|   %ind2 = add nuw nsw i64 %ind, 10000
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|   %arrayidxA2 = getelementptr i16, i16* %a, i64 %ind2
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| 
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|   %loadA1 = load i16, i16* %arrayidxA1, align 2
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|   %loadA2 = load i16, i16* %arrayidxA2, align 2
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| 
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|   %addres = add i16 %loadA1, %loadA2
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| 
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|   %storeidx = getelementptr inbounds i16, i16* %a, i64 %store_ind
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|   store i16 %addres, i16* %storeidx, align 2
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| 
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|   %exitcond = icmp eq i64 %add, 5000
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|   br i1 %exitcond, label %for.end, label %for.body
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| 
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| for.end:                                          ; preds = %for.body
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|   ret void
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| }
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