[llvm-commits] [llvm] r132633 - /llvm/trunk/test/Transforms/GVN/phi-translate-partial-alias.ll

[Dan Gohman]

Author: djg
Date: Sat Jun  4 02:05:05 2011
New Revision: 132633

URL: http://llvm.org/viewvc/llvm-project?rev=132633&view=rev
Log:
Add a testcase to demonstrate the problem where phi translation is
ignored for clobbering partial-alias loads.

Added:
    llvm/trunk/test/Transforms/GVN/phi-translate-partial-alias.ll

Added: llvm/trunk/test/Transforms/GVN/phi-translate-partial-alias.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/GVN/phi-translate-partial-alias.ll?rev=132633&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/GVN/phi-translate-partial-alias.ll (added)
+++ llvm/trunk/test/Transforms/GVN/phi-translate-partial-alias.ll Sat Jun  4 02:05:05 2011
@@ -0,0 +1,27 @@
+; RUN: opt -basicaa -gvn -S < %s | FileCheck %s
+
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-f128:128:128-n8:16:32:64"
+
+; GVN shouldn't PRE the load around the loop backedge because it's
+; not actually redundant around the loop backedge, despite appearances
+; if phi-translation is ignored.
+
+; CHECK: define void @test0(i8* %begin)
+; CHECK: loop:
+; CHECK:   %l0 = load i8* %phi
+; CHECK:   call void @bar(i8 %l0)
+; CHECK:   %l1 = load i8* %phi
+define void @test0(i8* %begin) {
+entry:
+  br label %loop
+
+loop:
+  %phi = phi i8* [ %begin, %entry ], [ %next, %loop ]
+  %l0 = load i8* %phi
+  call void @bar(i8 %l0)
+  %l1 = load i8* %phi
+  %next = getelementptr inbounds i8* %phi, i8 %l1
+  br label %loop
+}
+
+declare void @bar(i8)