Disable statistics on Release builds and move tests that depend on -stats.

Summary:
Statistics are still available in Release+Asserts (any +Asserts builds),
and stats can also be turned on with LLVM_ENABLE_STATS.

Move some of the FastISel stats that were moved under DEBUG()
back out of DEBUG(), since stats are disabled across the board now.

Many tests depend on grepping "-stats" output.  Move those into
a orig_dir/Stats/. so that they can be marked as unsupported
when building without statistics.

Differential Revision: http://llvm-reviews.chandlerc.com/D486

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176733 91177308-0d34-0410-b5e6-96231b3b80d8

test/Transforms/MergeFunc/phi-speculation1.ll

@@ -1,29 +0,0 @@
-; RUN: opt < %s -mergefunc -stats -disable-output 2>&1 | not grep "functions merged"
-
-define i32 @foo1(i32 %x) {
-entry:
-  %A = add i32 %x, 1
-  %B = call i32 @foo1(i32 %A)
-  br label %loop
-loop:
-  %C = phi i32 [%B, %entry], [%D, %loop]
-  %D = add i32 %x, 2
-  %E = icmp ugt i32 %D, 10000
-  br i1 %E, label %loopexit, label %loop
-loopexit:
-  ret i32 %D
-}
-
-define i32 @foo2(i32 %x) {
-entry:
-  %0 = add i32 %x, 1
-  %1 = call i32 @foo2(i32 %0)
-  br label %loop
-loop:
-  %2 = phi i32 [%1, %entry], [%3, %loop]
-  %3 = add i32 %2, 2
-  %4 = icmp ugt i32 %3, 10000
-  br i1 %4, label %loopexit, label %loop
-loopexit:
-  ret i32 %3
-}