Add a new MergeFunctions pass. It finds identical functions and merges them.

This triggers only 60 times in llvm-test (look at .llvm.bc, not .linked.rbc)
and so it probably wont be turned on by default. Also, may of those are likely
to go away when PR2973 is fixed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@58557 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 61 insertions, 0 deletions

diff --git a/test/Transforms/MergeFunc/dg.exp b/test/Transforms/MergeFunc/dg.exp
new file mode 100644
index 0000000000..f2005891a5
--- /dev/null
+++ b/test/Transforms/MergeFunc/dg.exp
@@ -0,0 +1,3 @@
+load_lib llvm.exp
+
+RunLLVMTests [lsort [glob -nocomplain $srcdir/$subdir/*.{ll,c,cpp}]]
diff --git a/test/Transforms/MergeFunc/phi-speculation1.ll b/test/Transforms/MergeFunc/phi-speculation1.ll
new file mode 100644
index 0000000000..89f31e3ada
--- /dev/null
+++ b/test/Transforms/MergeFunc/phi-speculation1.ll
@@ -0,0 +1,29 @@
+; RUN: llvm-as < %s | opt -mergefunc -stats | 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
+}
diff --git a/test/Transforms/MergeFunc/phi-speculation2.ll b/test/Transforms/MergeFunc/phi-speculation2.ll
new file mode 100644
index 0000000000..1649100200
--- /dev/null
+++ b/test/Transforms/MergeFunc/phi-speculation2.ll
@@ -0,0 +1,29 @@
+; RUN: llvm-as < %s | opt -mergefunc -stats |& 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 %C, 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
+}