Fix a thinko that manifested as a crash on clamav last night.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60251 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/Scalar/DeadStoreElimination.cpp b/lib/Transforms/Scalar/DeadStoreElimination.cpp
index 1b6d85086280321dc65bf11c6762ad83de162f27..0acc995e8722f705b6a4f333ed157587e928d1d1 100644 (file)
--- a/lib/Transforms/Scalar/DeadStoreElimination.cpp
+++ b/lib/Transforms/Scalar/DeadStoreElimination.cpp
@@ -130,7 +130,7 @@ bool DSE::runOnBasicBlock(BasicBlock &BB) {
       
       // If we deleted a store, reinvestigate this instruction.
       if (deletedStore) {
-        if (!isa<TerminatorInst>(BB.begin()))
+        if (BBI != BB.begin())
           --BBI;
         continue;
       }
@@ -157,7 +157,7 @@ bool DSE::runOnBasicBlock(BasicBlock &BB) {
             (!dep.isNormal() || DT.dominates(dep.getInst(), L))) {
           
           DeleteDeadInstruction(S);
-          if (!isa<TerminatorInst>(BB.begin()))
+          if (BBI != BB.begin())
             --BBI;
           NumFastStores++;
           MadeChange = true;

diff --git a/test/Transforms/DeadStoreElimination/2008-11-29-OffEndOfBlock.ll b/test/Transforms/DeadStoreElimination/2008-11-29-OffEndOfBlock.ll
new file mode 100644 (file)
index 0000000..11e2ffd
--- /dev/null
+++ b/test/Transforms/DeadStoreElimination/2008-11-29-OffEndOfBlock.ll
@@ -0,0 +1,27 @@
+; RUN: llvm-as < %s | opt -dse | llvm-dis
+
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
+target triple = "i386-apple-darwin7"
+       %struct.cab_archive = type { i32, i16, i16, i16, i16, i8, %struct.cab_folder*, %struct.cab_file* }
+       %struct.cab_file = type { i32, i16, i64, i8*, i32, i32, i32, %struct.cab_folder*, %struct.cab_file*, %struct.cab_archive*, %struct.cab_state* }
+       %struct.cab_folder = type { i16, i16, %struct.cab_archive*, i64, %struct.cab_folder* }
+       %struct.cab_state = type { i8*, i8*, [38912 x i8], i16, i16, i8*, i16 }
+       %struct.lzx_stream = type { i32, i32, i8, i64, i64, i8*, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i8, i8, i8, i8, i8, i32, i8*, i8*, i8*, i8*, i8*, i32, i32, i32, [84 x i8], [720 x i8], [314 x i8], [72 x i8], [104 x i16], [5408 x i16], [4596 x i16], [144 x i16], [51 x i32], [51 x i8], [32768 x i8], %struct.cab_file*, i32 (%struct.cab_file*, i8*, i32)* }
+
+declare fastcc i32 @lzx_read_lens(%struct.lzx_stream*, i8*, i32, i32) nounwind
+
+define i32 @lzx_decompress(%struct.lzx_stream* %lzx, i64 %out_bytes) nounwind {
+bb13:          ; preds = %entry
+       %0 = getelementptr %struct.lzx_stream* %lzx, i32 0, i32 25              ; <i8**> [#uses=2]
+       %1 = getelementptr %struct.lzx_stream* %lzx, i32 0, i32 26              ; <i8**> [#uses=2]
+       %2 = getelementptr %struct.lzx_stream* %lzx, i32 0, i32 29              ; <i32*> [#uses=0]
+       br label %bb14
+
+bb14:          ; preds = %bb13
+       %3 = load i8** %0, align 4              ; <i8*> [#uses=1]
+       %4 = load i8** %1, align 4              ; <i8*> [#uses=1]
+       store i8* %3, i8** %0, align 4
+       store i8* %4, i8** %1, align 4
+       %5 = call fastcc i32 @lzx_read_lens(%struct.lzx_stream* %lzx, i8* null, i32 256, i32 0) nounwind                ; <i32> [#uses=0]
+       unreachable
+}