Index: llvm/trunk/test/Transforms/InstCombine/onehot_merge.ll
===================================================================
--- llvm/trunk/test/Transforms/InstCombine/onehot_merge.ll
+++ llvm/trunk/test/Transforms/InstCombine/onehot_merge.ll
@@ -18,14 +18,14 @@
 define i1 @foo1_and(i32 %k, i32 %c1, i32 %c2) {
 ; CHECK-LABEL: @foo1_and(
 ; CHECK-NEXT:    [[T:%.*]] = shl i32 1, [[C1:%.*]]
-; CHECK-NEXT:    [[T4:%.*]] = lshr i32 -2147483648, [[C2:%.*]]
+; CHECK-NEXT:    [[T4:%.*]] = shl i32 1, [[C2:%.*]]
 ; CHECK-NEXT:    [[TMP1:%.*]] = or i32 [[T]], [[T4]]
 ; CHECK-NEXT:    [[TMP2:%.*]] = and i32 [[TMP1]], [[K:%.*]]
 ; CHECK-NEXT:    [[TMP3:%.*]] = icmp ne i32 [[TMP2]], [[TMP1]]
 ; CHECK-NEXT:    ret i1 [[TMP3]]
 ;
   %t = shl i32 1, %c1
-  %t4 = lshr i32 -2147483648, %c2
+  %t4 = shl i32 1, %c2
   %t1 = and i32 %t, %k
   %t2 = icmp eq i32 %t1, 0
   %t5 = and i32 %t4, %k
@@ -39,7 +39,7 @@
 ; CHECK-LABEL: @foo1_and_commuted(
 ; CHECK-NEXT:    [[K2:%.*]] = mul i32 [[K:%.*]], [[K]]
 ; CHECK-NEXT:    [[T:%.*]] = shl i32 1, [[C1:%.*]]
-; CHECK-NEXT:    [[T4:%.*]] = lshr i32 -2147483648, [[C2:%.*]]
+; CHECK-NEXT:    [[T4:%.*]] = shl i32 1, [[C2:%.*]]
 ; CHECK-NEXT:    [[TMP1:%.*]] = or i32 [[T]], [[T4]]
 ; CHECK-NEXT:    [[TMP2:%.*]] = and i32 [[K2]], [[TMP1]]
 ; CHECK-NEXT:    [[TMP3:%.*]] = icmp ne i32 [[TMP2]], [[TMP1]]
@@ -47,7 +47,7 @@
 ;
   %k2 = mul i32 %k, %k ; to trick the complexity sorting
   %t = shl i32 1, %c1
-  %t4 = lshr i32 -2147483648, %c2
+  %t4 = shl i32 1, %c2
   %t1 = and i32 %k2, %t
   %t2 = icmp eq i32 %t1, 0
   %t5 = and i32 %t4, %k2
@@ -73,14 +73,14 @@
 define i1 @foo1_or(i32 %k, i32 %c1, i32 %c2) {
 ; CHECK-LABEL: @foo1_or(
 ; CHECK-NEXT:    [[T:%.*]] = shl i32 1, [[C1:%.*]]
-; CHECK-NEXT:    [[T4:%.*]] = lshr i32 -2147483648, [[C2:%.*]]
+; CHECK-NEXT:    [[T4:%.*]] = shl i32 1, [[C2:%.*]]
 ; CHECK-NEXT:    [[TMP1:%.*]] = or i32 [[T]], [[T4]]
 ; CHECK-NEXT:    [[TMP2:%.*]] = and i32 [[TMP1]], [[K:%.*]]
 ; CHECK-NEXT:    [[TMP3:%.*]] = icmp eq i32 [[TMP2]], [[TMP1]]
 ; CHECK-NEXT:    ret i1 [[TMP3]]
 ;
   %t = shl i32 1, %c1
-  %t4 = lshr i32 -2147483648, %c2
+  %t4 = shl i32 1, %c2
   %t1 = and i32 %t, %k
   %t2 = icmp ne i32 %t1, 0
   %t5 = and i32 %t4, %k
@@ -94,7 +94,7 @@
 ; CHECK-LABEL: @foo1_or_commuted(
 ; CHECK-NEXT:    [[K2:%.*]] = mul i32 [[K:%.*]], [[K]]
 ; CHECK-NEXT:    [[T:%.*]] = shl i32 1, [[C1:%.*]]
-; CHECK-NEXT:    [[T4:%.*]] = lshr i32 -2147483648, [[C2:%.*]]
+; CHECK-NEXT:    [[T4:%.*]] = shl i32 1, [[C2:%.*]]
 ; CHECK-NEXT:    [[TMP1:%.*]] = or i32 [[T]], [[T4]]
 ; CHECK-NEXT:    [[TMP2:%.*]] = and i32 [[K2]], [[TMP1]]
 ; CHECK-NEXT:    [[TMP3:%.*]] = icmp eq i32 [[TMP2]], [[TMP1]]
@@ -102,7 +102,7 @@
 ;
   %k2 = mul i32 %k, %k ; to trick the complexity sorting
   %t = shl i32 1, %c1
-  %t4 = lshr i32 -2147483648, %c2
+  %t4 = shl i32 1, %c2
   %t1 = and i32 %k2, %t
   %t2 = icmp ne i32 %t1, 0
   %t5 = and i32 %t4, %k2
@@ -110,3 +110,41 @@
   %or = and i1 %t2, %t6
   ret i1 %or
 }
+
+define i1 @foo1_and_signbit_lshr(i32 %k, i32 %c1, i32 %c2) {
+; CHECK-LABEL: @foo1_and_signbit_lshr(
+; CHECK-NEXT:    [[T:%.*]] = shl i32 1, [[C1:%.*]]
+; CHECK-NEXT:    [[T4:%.*]] = lshr i32 -2147483648, [[C2:%.*]]
+; CHECK-NEXT:    [[TMP1:%.*]] = or i32 [[T]], [[T4]]
+; CHECK-NEXT:    [[TMP2:%.*]] = and i32 [[TMP1]], [[K:%.*]]
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp ne i32 [[TMP2]], [[TMP1]]
+; CHECK-NEXT:    ret i1 [[TMP3]]
+;
+  %t = shl i32 1, %c1
+  %t4 = lshr i32 -2147483648, %c2
+  %t1 = and i32 %t, %k
+  %t2 = icmp eq i32 %t1, 0
+  %t5 = and i32 %t4, %k
+  %t6 = icmp eq i32 %t5, 0
+  %or = or i1 %t2, %t6
+  ret i1 %or
+}
+
+define i1 @foo1_or_signbit_lshr(i32 %k, i32 %c1, i32 %c2) {
+; CHECK-LABEL: @foo1_or_signbit_lshr(
+; CHECK-NEXT:    [[T:%.*]] = shl i32 1, [[C1:%.*]]
+; CHECK-NEXT:    [[T4:%.*]] = lshr i32 -2147483648, [[C2:%.*]]
+; CHECK-NEXT:    [[TMP1:%.*]] = or i32 [[T]], [[T4]]
+; CHECK-NEXT:    [[TMP2:%.*]] = and i32 [[TMP1]], [[K:%.*]]
+; CHECK-NEXT:    [[TMP3:%.*]] = icmp eq i32 [[TMP2]], [[TMP1]]
+; CHECK-NEXT:    ret i1 [[TMP3]]
+;
+  %t = shl i32 1, %c1
+  %t4 = lshr i32 -2147483648, %c2
+  %t1 = and i32 %t, %k
+  %t2 = icmp ne i32 %t1, 0
+  %t5 = and i32 %t4, %k
+  %t6 = icmp ne i32 %t5, 0
+  %or = and i1 %t2, %t6
+  ret i1 %or
+}