[llvm] improve debug messages in delinearization and dependence analysis (PR #156339)

[Ryotaro Kasuga via llvm-commits]

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@@ -11,10 +11,9 @@
 define void @foo(i64 %n, i64 %m, i64 %o, ptr nocapture %A) #0 {
 ; CHECK-LABEL: 'foo'
 ; CHECK-NEXT:  Inst: store i32 1, ptr %arrayidx11.us.us, align 4
-; CHECK-NEXT:  In Loop with Header: for.k
-; CHECK-NEXT:  AccessFunction: {{\{\{\{}}(28 + (4 * (-4 + (3 * %m)) * %o)),+,(8 * %m * %o)}<%for.i>,+,(12 * %o)}<%for.j>,+,20}<%for.k>
+; CHECK-NEXT:  LinearAccessFunction: {{\{\{\{}}(28 + (4 * (-4 + (3 * %m)) * %o)),+,(8 * %m * %o)}<%for.i>,+,(12 * %o)}<%for.j>,+,20}<%for.k>
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kasuga-fj wrote:

I think `LinearAccessFunction` is misleading. When I see the term "Linear Function," I imagine a [linear function](https://en.wikipedia.org/wiki/Linear_function_(calculus)), but that is not the case. E.g., an expression like `i * i` can also appear here.

https://github.com/llvm/llvm-project/pull/156339