From bf5a2c6a39f2a98a83f5fb668b8b35156b693471 Mon Sep 17 00:00:00 2001 From: Nadav Rotem Date: Wed, 19 Dec 2012 07:39:08 +0000 Subject: After reducing the size of an operation in the DAG we zero-extend the reduced bitwidth op back to the original size. If we reduce ANDs then this can cause an endless loop. This patch changes the ZEXT to ANY_EXTEND if the demanded bits are equal or smaller than the size of the reduced operation. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170505 91177308-0d34-0410-b5e6-96231b3b80d8 --- test/CodeGen/Generic/dag-combine-crash.ll | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) create mode 100644 test/CodeGen/Generic/dag-combine-crash.ll (limited to 'test/CodeGen/Generic') diff --git a/test/CodeGen/Generic/dag-combine-crash.ll b/test/CodeGen/Generic/dag-combine-crash.ll new file mode 100644 index 0000000..a7810b5 --- /dev/null +++ b/test/CodeGen/Generic/dag-combine-crash.ll @@ -0,0 +1,21 @@ +; RUN: llc < %s + +define void @main() { +if.end: + br label %block.i.i + +block.i.i: + %tmpbb = load i8* undef + %tmp54 = zext i8 %tmpbb to i64 + %tmp59 = and i64 %tmp54, 8 + %tmp60 = add i64 %tmp59, 3691045929300498764 + %tmp62 = sub i64 %tmp60, 3456506383779105993 + %tmp63 = xor i64 1050774804270620004, %tmp62 + %tmp65 = xor i64 %tmp62, 234539545521392771 + %tmp67 = or i64 %tmp65, %tmp63 + %tmp71 = xor i64 %tmp67, 6781485823212740913 + %tmp72 = trunc i64 %tmp71 to i32 + %tmp74 = lshr i32 2, %tmp72 + store i32 %tmp74, i32* undef + br label %block.i.i +} -- cgit v1.1