-; RUN: opt < %s -loop-interchange -verify-dom-info -verify-loop-info -S \
-; RUN: -pass-remarks=loop-interchange 2>&1 | FileCheck %s
-; CHECK: Loop interchanged with enclosing loop.
+; RUN: opt < %s -loop-interchange -simplifycfg -pass-remarks-output=%t \
+; RUN: -pass-remarks=loop-interchange -pass-remarks-missed=loop-interchange -stats -S 2>&1 \
+; RUN: | FileCheck -check-prefix=STATS %s
+; RUN: FileCheck -input-file %t %s
-; no_deps_interchange just access a single nested array and can be interchange.
-define i32 @no_deps_interchange([1024 x i32]* nocapture %Arr, i32 %k) local_unnamed_addr #0 {
+; no_deps_interchange just accesses a single nested array and can be interchange.
+; CHECK: Name: Interchanged
+; CHECK-NEXT: Function: no_deps_interchange
+define i32 @no_deps_interchange([1024 x i32]* nocapture %Arr) local_unnamed_addr #0 {
entry:
- br label %for.body
+ br label %for1.header
-for.body: ; preds = %entry, %for.cond.cleanup3
- %indvars.iv19 = phi i64 [ 0, %entry ], [ %indvars.iv.next20, %for.cond.cleanup3 ]
- br label %for.body4
+for1.header: ; preds = %entry, %for1.inc
+ %indvars.iv19 = phi i64 [ 0, %entry ], [ %indvars.iv.next20, %for1.inc ]
+ br label %for2
-for.body4: ; preds = %for.body, %for.body4
- %indvars.iv = phi i64 [ 0, %for.body ], [ %indvars.iv.next, %for.body4 ]
+for2: ; preds = %for1.header, %for2
+ %indvars.iv = phi i64 [ 0, %for1.header ], [ %indvars.iv.next, %for2 ]
%arrayidx6 = getelementptr inbounds [1024 x i32], [1024 x i32]* %Arr, i64 %indvars.iv, i64 %indvars.iv19
store i32 0, i32* %arrayidx6, align 4
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%exitcond = icmp ne i64 %indvars.iv.next, 1024
- br i1 %exitcond, label %for.body4, label %for.cond.cleanup3
+ br i1 %exitcond, label %for2, label %for1.inc
-for.cond.cleanup3: ; preds = %for.body4
+for1.inc:
%indvars.iv.next20 = add nuw nsw i64 %indvars.iv19, 1
%exitcond21 = icmp ne i64 %indvars.iv.next20, 1024
- br i1 %exitcond21, label %for.body, label %for.cond.cleanup
+ br i1 %exitcond21, label %for1.header, label %exit
+exit: ; preds = %for1.inc
+ ret i32 0
+
+}
+
+; Only the inner loop induction variable is used for memory accesses.
+; Interchanging is not beneficial.
+; CHECK: Name: InterchangeNotProfitable
+; CHECK-NEXT: Function: no_bad_order
+define i32 @no_bad_order(i32* %Arr) {
+entry:
+ br label %for1.header
+
+for1.header: ; preds = %entry, %for1.inc
+ %indvars.iv19 = phi i64 [ 0, %entry ], [ %indvars.iv.next20, %for1.inc ]
+ br label %for2
+
+for2: ; preds = %for1.header, %for2
+ %indvars.iv = phi i64 [ 0, %for1.header ], [ %indvars.iv.next, %for2 ]
+ %arrayidx6 = getelementptr inbounds i32, i32* %Arr, i64 %indvars.iv
+ store i32 0, i32* %arrayidx6, align 4
+ %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+ %exitcond = icmp ne i64 %indvars.iv.next, 1024
+ br i1 %exitcond, label %for2, label %for1.inc
-for.cond.cleanup: ; preds = %for.cond.cleanup3
+for1.inc:
+ %indvars.iv.next20 = add nuw nsw i64 %indvars.iv19, 1
+ %exitcond21 = icmp ne i64 %indvars.iv.next20, 1024
+ br i1 %exitcond21, label %for1.header, label %exit
+
+exit: ; preds = %for1.inc
ret i32 0
}
+
+; No memory access using any induction variables, interchanging not beneficial.
+; CHECK: Name: InterchangeNotProfitable
+; CHECK-NEXT: Function: no_mem_instrs
+define i32 @no_mem_instrs(i64* %ptr) {
+entry:
+ br label %for1.header
+
+for1.header: ; preds = %entry, %for1.inc
+ %indvars.iv19 = phi i64 [ 0, %entry ], [ %indvars.iv.next20, %for1.inc ]
+ br label %for2
+
+for2: ; preds = %for1.header, %for2
+ %indvars.iv = phi i64 [ 0, %for1.header ], [ %indvars.iv.next, %for2 ]
+ store i64 %indvars.iv, i64* %ptr, align 4
+ %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+ %exitcond = icmp ne i64 %indvars.iv.next, 1024
+ br i1 %exitcond, label %for2, label %for1.inc
+
+for1.inc:
+ %indvars.iv.next20 = add nuw nsw i64 %indvars.iv19, 1
+ %exitcond21 = icmp ne i64 %indvars.iv.next20, 1024
+ br i1 %exitcond21, label %for1.header, label %exit
+
+exit: ; preds = %for1.inc
+ ret i32 0
+}
+
+
+; Check stats, we interchanged 1 out of 3 loops.
+; STATS: 1 loop-interchange - Number of loops interchanged