make instcombine's instruction sinking more aggressive in the

presence of PHI nodes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84103 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 37 insertions, 1 deletions

diff --git a/test/Transforms/InstCombine/sink_instruction.ll b/test/Transforms/InstCombine/sink_instruction.ll
index c46d210548..e521de208f 100644
--- a/test/Transforms/InstCombine/sink_instruction.ll
+++ b/test/Transforms/InstCombine/sink_instruction.ll
@@ -3,7 +3,8 @@
 ;; This tests that the instructions in the entry blocks are sunk into each
 ;; arm of the 'if'.
 
-define i32 @foo(i1 %C, i32 %A, i32 %B) {
+define i32 @test1(i1 %C, i32 %A, i32 %B) {
+; CHECK: @test1
 entry:
         %tmp.2 = sdiv i32 %A, %B                ; <i32> [#uses=1]
         %tmp.9 = add i32 %B, %A         ; <i32> [#uses=1]
@@ -18,3 +19,38 @@ endif:          ; preds = %entry
         ret i32 %tmp.2
 }
 
+
+;; PHI use, sink divide before call.
+define i32 @test2(i32 %x) nounwind ssp {
+; CHECK: @test2
+; CHECK-NOT: sdiv i32
+entry:
+  br label %bb
+
+bb:                                               ; preds = %bb2, %entry
+  %x_addr.17 = phi i32 [ %x, %entry ], [ %x_addr.0, %bb2 ] ; <i32> [#uses=4]
+  %i.06 = phi i32 [ 0, %entry ], [ %4, %bb2 ]     ; <i32> [#uses=1]
+  %0 = add nsw i32 %x_addr.17, 1                  ; <i32> [#uses=1]
+  %1 = sdiv i32 %0, %x_addr.17                    ; <i32> [#uses=1]
+  %2 = icmp eq i32 %x_addr.17, 0                  ; <i1> [#uses=1]
+  br i1 %2, label %bb1, label %bb2
+
+bb1:                                              ; preds = %bb
+; CHECK: bb1:
+; CHECK-NEXT: add nsw i32 %x_addr.17, 1
+; CHECK-NEXT: sdiv i32
+; CHECK-NEXT: tail call i32 @bar()
+  %3 = tail call i32 @bar() nounwind       ; <i32> [#uses=0]
+  br label %bb2
+
+bb2:                                              ; preds = %bb, %bb1
+  %x_addr.0 = phi i32 [ %1, %bb1 ], [ %x_addr.17, %bb ] ; <i32> [#uses=2]
+  %4 = add nsw i32 %i.06, 1                       ; <i32> [#uses=2]
+  %exitcond = icmp eq i32 %4, 1000000             ; <i1> [#uses=1]
+  br i1 %exitcond, label %bb4, label %bb
+
+bb4:                                              ; preds = %bb2
+  ret i32 %x_addr.0
+}
+
+declare i32 @bar()