summaryrefslogtreecommitdiff
path: root/test
diff options
context:
space:
mode:
authorJuergen Ributzka <juergen@apple.com>2014-02-06 04:09:06 +0000
committerJuergen Ributzka <juergen@apple.com>2014-02-06 04:09:06 +0000
commit58bc0ca37b66bf49bc20661fd2748319a06808c3 (patch)
tree8eeca97141e70f357a7aca2a01af8b3f85f86528 /test
parentc7ac256d525988388c79c8c821a6c2e5d144ae68 (diff)
downloadllvm-58bc0ca37b66bf49bc20661fd2748319a06808c3.tar.gz
llvm-58bc0ca37b66bf49bc20661fd2748319a06808c3.tar.bz2
llvm-58bc0ca37b66bf49bc20661fd2748319a06808c3.tar.xz
[DAG] Don't pull the binary operation though the shift if the operands have opaque constants.
During DAGCombine visitShiftByConstant assumes that certain binary operations with only constant operands can always be folded successfully. This is no longer true when the constant is opaque. This commit fixes visitShiftByConstant by not performing the optimization for opaque constants. Otherwise we would end up in an infinite DAGCombine loop. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200900 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test')
-rw-r--r--test/CodeGen/Generic/2014-02-05-OpaqueConstants.ll19
1 files changed, 19 insertions, 0 deletions
diff --git a/test/CodeGen/Generic/2014-02-05-OpaqueConstants.ll b/test/CodeGen/Generic/2014-02-05-OpaqueConstants.ll
new file mode 100644
index 0000000000..5c1cd05325
--- /dev/null
+++ b/test/CodeGen/Generic/2014-02-05-OpaqueConstants.ll
@@ -0,0 +1,19 @@
+; Test that opaque constants are not creating an infinite DAGCombine loop
+; RUN: llc < %s
+; XFAIL: r600, xcore
+
+@a = common global i32* null, align 8
+@c = common global i32 0, align 4
+@b = common global i32* null, align 8
+
+; Function Attrs: nounwind ssp uwtable
+define void @fn() {
+ store i32* inttoptr (i64 68719476735 to i32*), i32** @a, align 8
+ %1 = load i32* @c, align 4
+ %2 = sext i32 %1 to i64
+ %3 = lshr i64 %2, 12
+ %4 = and i64 %3, 68719476735
+ %5 = getelementptr inbounds i32* null, i64 %4
+ store i32* %5, i32** @b, align 8
+ ret void
+}