Index: llvm/lib/Transforms/Scalar/GVNHoist.cpp
===================================================================
--- llvm/lib/Transforms/Scalar/GVNHoist.cpp
+++ llvm/lib/Transforms/Scalar/GVNHoist.cpp
@@ -936,10 +936,17 @@
     HoistingPointList HPL;
     computeInsertionPoints(II.getVNTable(), HPL, InsKind::Scalar);
     computeInsertionPoints(LI.getVNTable(), HPL, InsKind::Load);
-    computeInsertionPoints(SI.getVNTable(), HPL, InsKind::Store);
     computeInsertionPoints(CI.getScalarVNTable(), HPL, InsKind::Scalar);
     computeInsertionPoints(CI.getLoadVNTable(), HPL, InsKind::Load);
-    computeInsertionPoints(CI.getStoreVNTable(), HPL, InsKind::Store);
+
+    // Hoisting stores is difficult: see PR30216; disabled until either we fix
+    // the dependence analysis, or we decide to only sink the stores.  In
+    // principle stores should be by default sinked, unless doing so would
+    // increase the live range of stored values.
+    if (0) {
+      computeInsertionPoints(SI.getVNTable(), HPL, InsKind::Store);
+      computeInsertionPoints(CI.getStoreVNTable(), HPL, InsKind::Store);
+    }
     return hoist(HPL);
   }
 };
Index: llvm/test/Transforms/GVNHoist/hoist-md.ll
===================================================================
--- llvm/test/Transforms/GVNHoist/hoist-md.ll
+++ llvm/test/Transforms/GVNHoist/hoist-md.ll
@@ -18,8 +18,7 @@
   ret void
 }
 ; CHECK-LABEL: define void @test1(
-; CHECK: store i32 2, i32* %x, align 4
-; CHECK-NEXT: br i1 %b
+; Store hoisting is disabled.
 
 define void @test2(i1 %b, i32* %x) {
 entry:
@@ -39,9 +38,7 @@
   ret void
 }
 ; CHECK-LABEL: define void @test2(
-; CHECK: %[[gep:.*]] = getelementptr inbounds i32, i32* %x, i64 1
-; CHECK: store i32 2, i32* %[[gep]], align 4
-; CHECK-NEXT: br i1 %b
+; Store hoisting is disabled.
 
 define void @test3(i1 %b, i32* %x) {
 entry:
@@ -61,9 +58,7 @@
   ret void
 }
 ; CHECK-LABEL: define void @test3(
-; CHECK: %[[gep:.*]] = getelementptr i32, i32* %x, i64 1
-; CHECK: store i32 2, i32* %[[gep]], align 4
-; CHECK-NEXT: br i1 %b
+; Store hoisting is disabled.
 
 !1 = !{!2, !2, i64 0}
 !2 = !{!"int", !3, i64 0}
Index: llvm/test/Transforms/GVNHoist/hoist-mssa.ll
===================================================================
--- llvm/test/Transforms/GVNHoist/hoist-mssa.ll
+++ llvm/test/Transforms/GVNHoist/hoist-mssa.ll
@@ -1,9 +1,9 @@
 ; RUN: opt -S -gvn-hoist < %s | FileCheck %s
 
-; Check that store hoisting works: there should be only one store left.
+; Store hoisting is disabled.
 ; CHECK-LABEL: @getopt
 ; CHECK: store i32
-; CHECK-NOT: store i32
+; CHECK: store i32
 
 @optind = external global i32, align 4
 
@@ -49,10 +49,10 @@
 
 @GlobalVar = internal global float 1.000000e+00
 
-; Check that we hoist stores and remove the MSSA phi node.
+; Store hoisting is disabled.
 ; CHECK-LABEL: @hoistStoresUpdateMSSA
 ; CHECK: store float
-; CHECK-NOT: store float
+; CHECK: store float
 define float @hoistStoresUpdateMSSA(float %d) {
 entry:
   store float 0.000000e+00, float* @GlobalVar
Index: llvm/test/Transforms/GVNHoist/hoist-pr28606.ll
===================================================================
--- llvm/test/Transforms/GVNHoist/hoist-pr28606.ll
+++ llvm/test/Transforms/GVNHoist/hoist-pr28606.ll
@@ -17,9 +17,9 @@
 ; CHECK: alloca inalloca
 ; CHECK-NOT: alloca i8
 
-; Check that store instructions are hoisted.
+; Store hoisting is disabled.
+; CHECK: store i8
 ; CHECK: store i8
-; CHECK-NOT: store i8
 ; CHECK: stackrestore
 
 define void @test(i1 %b) {
Index: llvm/test/Transforms/GVNHoist/hoist-pr28933.ll
===================================================================
--- llvm/test/Transforms/GVNHoist/hoist-pr28933.ll
+++ llvm/test/Transforms/GVNHoist/hoist-pr28933.ll
@@ -1,11 +1,11 @@
 ; RUN: opt -S -gvn-hoist -verify-memoryssa < %s | FileCheck %s
 
-; Check that we end up with one load and one store, in the right order
+; Store hoisting is disabled.
 ; CHECK-LABEL:  define void @test_it(
 ; CHECK: store
 ; CHECK-NEXT: load
-; CHECK-NOT: store
-; CHECK-NOT: load
+; CHECK: store
+; CHECK: load
         
 %rec894.0.1.2.3.12 = type { i16 }
 
Index: llvm/test/Transforms/GVNHoist/hoist.ll
===================================================================
--- llvm/test/Transforms/GVNHoist/hoist.ll
+++ llvm/test/Transforms/GVNHoist/hoist.ll
@@ -627,24 +627,8 @@
   ret float %add
 }
 
-; Check that we hoist stores: all the instructions from the then branch
-; should be hoisted.
+; Store hoisting is disabled.
 ; CHECK-LABEL: @hoistStores
-; CHECK: zext
-; CHECK-NEXT: trunc
-; CHECK-NEXT: getelementptr
-; CHECK-NEXT: load
-; CHECK-NEXT: getelementptr
-; CHECK-NEXT: getelementptr
-; CHECK-NEXT: store
-; CHECK-NEXT: load
-; CHECK-NEXT: load
-; CHECK-NEXT: zext
-; CHECK-NEXT: add
-; CHECK-NEXT: store
-; CHECK-NEXT: br
-; CHECK: if.then
-; CHECK: br
 
 %struct.foo = type { i16* }
 
Index: llvm/test/Transforms/GVNHoist/pr30216.ll
===================================================================
--- /dev/null
+++ llvm/test/Transforms/GVNHoist/pr30216.ll
@@ -0,0 +1,26 @@
+; RUN: opt -S -gvn-hoist < %s | FileCheck %s
+
+; Make sure the two stores @B do not get hoisted past the load @B.
+
+; CHECK-LABEL: define i8* @Foo
+; CHECK: store
+; CHECK: store
+; CHECK: load
+; CHECK: store
+
+@A = external global i8
+@B = external global i8*
+
+define i8* @Foo() {
+  store i8 0, i8* @A
+  br i1 undef, label %if.then, label %if.else
+
+if.then:
+  store i8* null, i8** @B
+  ret i8* null
+
+if.else:
+  %1 = load i8*, i8** @B
+  store i8* null, i8** @B
+  ret i8* %1
+}