diff --git a/clang/docs/ClangFormatStyleOptions.rst b/clang/docs/ClangFormatStyleOptions.rst
--- a/clang/docs/ClangFormatStyleOptions.rst
+++ b/clang/docs/ClangFormatStyleOptions.rst
@@ -2287,6 +2287,9 @@
      int a[ 5 ];                    vs.     int a[5];
      std::unique_ptr<int[]> foo() {} // Won't be affected
 
+**SpacesInConditionalStatement** (``bool``)
+  If ``true``, spaces will be inserted around if/for/while (and similar) conditions.
+
 **Standard** (``LanguageStandard``)
   Format compatible with this standard, e.g. use ``A<A<int> >``
   instead of ``A<A<int>>`` for ``LS_Cpp03``.
diff --git a/clang/include/clang/Format/Format.h b/clang/include/clang/Format/Format.h
--- a/clang/include/clang/Format/Format.h
+++ b/clang/include/clang/Format/Format.h
@@ -1945,6 +1945,15 @@
   /// \endcode
   bool SpacesInSquareBrackets;
 
+  /// If ``true``, spaces will be inserted around if/for/switch/while
+  /// conditions.
+  /// \code
+  ///    true:                                  false:
+  ///    if ( a )  { ... }              vs.     if (a) { ... }
+  ///    while ( i < 5 )  { ... }               while (i < 5) { ... }
+  /// \endcode
+  bool SpacesInConditionalStatement;
+
   /// Supported language standards.
   enum LanguageStandard {
     /// Use C++03-compatible syntax.
@@ -2081,6 +2090,7 @@
            SpacesInCStyleCastParentheses == R.SpacesInCStyleCastParentheses &&
            SpacesInParentheses == R.SpacesInParentheses &&
            SpacesInSquareBrackets == R.SpacesInSquareBrackets &&
+           SpacesInConditionalStatement == R.SpacesInConditionalStatement &&
            Standard == R.Standard && TabWidth == R.TabWidth &&
            StatementMacros == R.StatementMacros && UseTab == R.UseTab &&
            TypenameMacros == R.TypenameMacros;
diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -511,6 +511,7 @@
     IO.mapOptional("SpacesBeforeTrailingComments",
                    Style.SpacesBeforeTrailingComments);
     IO.mapOptional("SpacesInAngles", Style.SpacesInAngles);
+    IO.mapOptional("SpacesInConditionalStatement", Style.SpacesInConditionalStatement);
     IO.mapOptional("SpacesInContainerLiterals",
                    Style.SpacesInContainerLiterals);
     IO.mapOptional("SpacesInCStyleCastParentheses",
@@ -775,6 +776,7 @@
   LLVMStyle.SpaceBeforeAssignmentOperators = true;
   LLVMStyle.SpaceBeforeCpp11BracedList = false;
   LLVMStyle.SpacesInAngles = false;
+  LLVMStyle.SpacesInConditionalStatement = false;
 
   LLVMStyle.PenaltyBreakAssignment = prec::Assignment;
   LLVMStyle.PenaltyBreakComment = 300;
diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -2489,6 +2489,13 @@
           Right.ParameterCount > 0);
 }
 
+/// Returns \c true if the token is followed by a boolean condition, \c false
+/// otherwise.
+static bool isKeywordWithCondition(const FormatToken &Tok) {
+  return Tok.isOneOf(tok::kw_if, tok::kw_for, tok::kw_while, tok::kw_switch,
+                     tok::kw_constexpr);
+};
+
 bool TokenAnnotator::spaceRequiredBetween(const AnnotatedLine &Line,
                                           const FormatToken &Left,
                                           const FormatToken &Right) {
@@ -2505,6 +2512,16 @@
     return Right.is(tok::hash);
   if (Left.is(tok::l_paren) && Right.is(tok::r_paren))
     return Style.SpaceInEmptyParentheses;
+  if (Style.SpacesInConditionalStatement) {
+    if (Left.is(tok::l_paren) && Left.Previous &&
+        isKeywordWithCondition(*Left.Previous) )
+      return true;
+    if (Right.is(tok::r_paren) &&
+        Right.MatchingParen &&
+        Right.MatchingParen->Previous &&
+        isKeywordWithCondition(*Right.MatchingParen->Previous))
+      return true;
+  }
   if (Left.is(tok::l_paren) || Right.is(tok::r_paren))
     return (Right.is(TT_CastRParen) ||
             (Left.MatchingParen && Left.MatchingParen->is(TT_CastRParen)))
@@ -2903,7 +2920,8 @@
     // The identifier might actually be a macro name such as ALWAYS_INLINE. If
     // this turns out to be too lenient, add analysis of the identifier itself.
     return Right.WhitespaceRange.getBegin() != Right.WhitespaceRange.getEnd();
-  if (Right.is(tok::coloncolon) && !Left.isOneOf(tok::l_brace, tok::comment))
+  if (Right.is(tok::coloncolon) &&
+      !Left.isOneOf(tok::l_brace, tok::comment, tok::l_paren))
     return (Left.is(TT_TemplateOpener) &&
             Style.Standard < FormatStyle::LS_Cpp11) ||
            !(Left.isOneOf(tok::l_paren, tok::r_paren, tok::l_square,
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -12165,6 +12165,7 @@
   CHECK_PARSE_BOOL(SpacesInParentheses);
   CHECK_PARSE_BOOL(SpacesInSquareBrackets);
   CHECK_PARSE_BOOL(SpacesInAngles);
+  CHECK_PARSE_BOOL(SpacesInConditionalStatement);
   CHECK_PARSE_BOOL(SpaceInEmptyBlock);
   CHECK_PARSE_BOOL(SpaceInEmptyParentheses);
   CHECK_PARSE_BOOL(SpacesInContainerLiterals);
@@ -14373,6 +14374,23 @@
   verifyFormat("auto lambda = [&a = a]() { a = 2; };", AlignStyle);
 }
 
+TEST_F(FormatTest, SpacesInConditionalStatement) {
+  FormatStyle Spaces = getLLVMStyle();
+  Spaces.SpacesInConditionalStatement = true;
+  verifyFormat("for ( int i = 0; i; i++ )\n  continue;", Spaces);
+  verifyFormat("if ( !a )\n  return;", Spaces);
+  verifyFormat("if ( a )\n  return;", Spaces);
+  verifyFormat("if constexpr ( a )\n  return;", Spaces);
+  verifyFormat("switch ( a )\ncase 1:\n  return;", Spaces);
+  verifyFormat("while ( a )\n  return;", Spaces);
+  verifyFormat("while ( (a && b) )\n  return;", Spaces);
+  verifyFormat("do {\n} while ( 1 != 0 );", Spaces);
+
+  // Check that space on the left of "::" is inserted as expected at beginning
+  // of condition.
+  verifyFormat("while ( ::func() )\n  return;", Spaces);
+}
+
 } // end namespace
 } // end namespace format
 } // end namespace clang