Index: llvm/test/tools/llvm-reduce/reduce-conditionals.ll
===================================================================
--- /dev/null
+++ llvm/test/tools/llvm-reduce/reduce-conditionals.ll
@@ -0,0 +1,39 @@
+; RUN: llvm-reduce --abort-on-invalid-reduction --delta-passes=simplify-conditionals-true --test FileCheck --test-arg --check-prefixes=CHECK-INTERESTINGNESS --test-arg %s --test-arg --input-file %s -o %t
+; RUN: FileCheck --check-prefixes=RESULT-TRUE %s < %t
+
+; RUN: llvm-reduce --abort-on-invalid-reduction --delta-passes=simplify-conditionals-false --test FileCheck --test-arg --check-prefixes=CHECK-INTERESTINGNESS --test-arg %s --test-arg --input-file %s -o %t
+; RUN: FileCheck --check-prefixes=RESULT-FALSE %s < %t
+
+; CHECK-INTERESTINGNESS-LABEL: @func(
+; CHECK-INTERESTINGNESS: store i32 1,
+
+; RESULT-TRUE: bb0:
+; RESULT-TRUE: store i32 0, ptr null, align 4
+; RESULT-TRUE-NEXT: store i32 1, ptr null, align 4
+; RESULT-TRUE-NEXT: br label %bb2
+; RESULT-TRUE-NOT: bb1
+
+
+; RESULT-FALSE: bb0:
+; RESULT-FALSE: store i32 0, ptr null, align 4
+; RESULT-FALSE-NEXT: br label %bb2
+
+; RESULT-FALSE: bb1: ; No predecessors!
+; RESULT-FALSE-NEXT: store i32 1, ptr null, align 4
+; RESULT-FALSE-NEXT: br label %bb3
+define void @func(i1 %cond0, i1 %cond1) {
+bb0:
+  store i32 0, ptr null
+  br i1 %cond0, label %bb1, label %bb2
+
+bb1:
+  store i32 1, ptr null
+  br i1 %cond1, label %bb2, label %bb3
+
+bb2:
+  store i32 2, ptr null
+  br label %bb3
+
+bb3:
+  ret void
+}
Index: llvm/tools/llvm-reduce/DeltaManager.cpp
===================================================================
--- llvm/tools/llvm-reduce/DeltaManager.cpp
+++ llvm/tools/llvm-reduce/DeltaManager.cpp
@@ -70,6 +70,8 @@
     DELTA_PASS("function-bodies", reduceFunctionBodiesDeltaPass)               \
     DELTA_PASS("special-globals", reduceSpecialGlobalsDeltaPass)               \
     DELTA_PASS("aliases", reduceAliasesDeltaPass)                              \
+    DELTA_PASS("simplify-conditionals-true", reduceConditionalsTrueDeltaPass)  \
+    DELTA_PASS("simplify-conditionals-false", reduceConditionalsFalseDeltaPass)\
     DELTA_PASS("basic-blocks", reduceBasicBlocksDeltaPass)                     \
     DELTA_PASS("global-values", reduceGlobalValuesDeltaPass)                   \
     DELTA_PASS("global-objects", reduceGlobalObjectsDeltaPass)                 \
Index: llvm/tools/llvm-reduce/deltas/ReduceUsingSimplifyCFG.h
===================================================================
--- llvm/tools/llvm-reduce/deltas/ReduceUsingSimplifyCFG.h
+++ llvm/tools/llvm-reduce/deltas/ReduceUsingSimplifyCFG.h
@@ -18,6 +18,8 @@
 
 namespace llvm {
 void reduceUsingSimplifyCFGDeltaPass(TestRunner &Test);
+void reduceConditionalsTrueDeltaPass(TestRunner &Test);
+void reduceConditionalsFalseDeltaPass(TestRunner &Test);
 } // namespace llvm
 
 #endif
Index: llvm/tools/llvm-reduce/deltas/ReduceUsingSimplifyCFG.cpp
===================================================================
--- llvm/tools/llvm-reduce/deltas/ReduceUsingSimplifyCFG.cpp
+++ llvm/tools/llvm-reduce/deltas/ReduceUsingSimplifyCFG.cpp
@@ -13,6 +13,8 @@
 
 #include "ReduceUsingSimplifyCFG.h"
 #include "llvm/Analysis/TargetTransformInfo.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/Instructions.h"
 #include "llvm/Transforms/Utils/Local.h"
 
 using namespace llvm;
@@ -32,3 +34,35 @@
   outs() << "*** Reducing using SimplifyCFG...\n";
   runDeltaPass(Test, reduceUsingSimplifyCFG);
 }
+static void reduceConditionals(Oracle &O, Module &M, bool Direction) {
+  SmallVector<BasicBlock *, 16> ToSimplify;
+
+  for (auto &F : M) {
+    for (auto &BB : F) {
+      auto *BR = dyn_cast<BranchInst>(BB.getTerminator());
+      if (!BR || !BR->isConditional() || O.shouldKeep())
+        continue;
+
+      if (Direction)
+        BR->setCondition(ConstantInt::getTrue(BR->getContext()));
+      else
+        BR->setCondition(ConstantInt::getFalse(BR->getContext()));
+
+      ToSimplify.push_back(&BB);
+    }
+  }
+
+  TargetTransformInfo TTI(M.getDataLayout());
+  for (auto *BB : ToSimplify)
+    simplifyCFG(BB, TTI);
+}
+
+void llvm::reduceConditionalsTrueDeltaPass(TestRunner &Test) {
+  outs() << "*** Reducing conditional branches to true...\n";
+  runDeltaPass(Test, [](Oracle &O, Module &M) { reduceConditionals(O, M, true); });
+}
+
+void llvm::reduceConditionalsFalseDeltaPass(TestRunner &Test) {
+  outs() << "*** Reducing conditional branches to false...\n";
+  runDeltaPass(Test, [](Oracle &O, Module &M) { reduceConditionals(O, M, false); });
+}