Fix the bitcode reader to deserialize nuw/nsw/etc. bits properly in the case

of a forward-reference, which doesn't use an "abbrev" encoding.

llvm-svn: 94454

1 files changed, 27 insertions, 0 deletions

diff --git a/llvm/test/Bitcode/flags.ll b/llvm/test/Bitcode/flags.ll
new file mode 100644
index 00000000000..7b0c5b53889
--- /dev/null
+++ b/llvm/test/Bitcode/flags.ll
@@ -0,0 +1,27 @@
+; RUN: llvm-as < %s | llvm-dis > %t0
+; RUN: opt -S < %s > %t1
+; RUN: diff %t0 %t1
+; PR6140
+
+; Make sure the flags are serialized/deserialized properly for both
+; forward and backward references.
+
+define void @foo() nounwind {
+entry:
+  br label %first
+
+second:                                           ; preds = %first
+  %u = add nuw i32 %a, 0                          ; <i32> [#uses=0]
+  %s = add nsw i32 %a, 0                          ; <i32> [#uses=0]
+  %us = add nuw nsw i32 %a, 0                     ; <i32> [#uses=0]
+  %z = add i32 %a, 0                              ; <i32> [#uses=0]
+  unreachable
+
+first:                                            ; preds = %entry
+  %a = bitcast i32 0 to i32                       ; <i32> [#uses=8]
+  %uu = add nuw i32 %a, 0                         ; <i32> [#uses=0]
+  %ss = add nsw i32 %a, 0                         ; <i32> [#uses=0]
+  %uuss = add nuw nsw i32 %a, 0                   ; <i32> [#uses=0]
+  %zz = add i32 %a, 0                             ; <i32> [#uses=0]
+  br label %second
+}