Index: clang/docs/ReleaseNotes.rst
===================================================================
--- clang/docs/ReleaseNotes.rst
+++ clang/docs/ReleaseNotes.rst
@@ -450,6 +450,8 @@
 - Clang now diagnoses overflow undefined behavior in a constant expression while
   evaluating a compound assignment with remainder as operand.
 - Add ``-Wreturn-local-addr``, a GCC alias for ``-Wreturn-stack-address``.
+- Clang now suppresses ``-Wlogical-op-parentheses`` on ``(x && a || b)`` and ``(a || b && x)``
+  only when ``x`` is a string literal.
 
 Non-comprehensive list of changes in this release
 -------------------------------------------------
Index: clang/lib/Sema/SemaExpr.cpp
===================================================================
--- clang/lib/Sema/SemaExpr.cpp
+++ clang/lib/Sema/SemaExpr.cpp
@@ -15434,38 +15434,21 @@
     Bop->getSourceRange());
 }
 
-/// Returns true if the given expression can be evaluated as a constant
-/// 'true'.
-static bool EvaluatesAsTrue(Sema &S, Expr *E) {
-  bool Res;
-  return !E->isValueDependent() &&
-         E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && Res;
-}
-
-/// Returns true if the given expression can be evaluated as a constant
-/// 'false'.
-static bool EvaluatesAsFalse(Sema &S, Expr *E) {
-  bool Res;
-  return !E->isValueDependent() &&
-         E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && !Res;
-}
-
 /// Look for '&&' in the left hand of a '||' expr.
 static void DiagnoseLogicalAndInLogicalOrLHS(Sema &S, SourceLocation OpLoc,
                                              Expr *LHSExpr, Expr *RHSExpr) {
   if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(LHSExpr)) {
     if (Bop->getOpcode() == BO_LAnd) {
-      // If it's "a && b || 0" don't warn since the precedence doesn't matter.
-      if (EvaluatesAsFalse(S, RHSExpr))
-        return;
-      // If it's "1 && a || b" don't warn since the precedence doesn't matter.
-      if (!EvaluatesAsTrue(S, Bop->getLHS()))
+      // If it's "string_literal && a || b" don't warn since the precedence
+      // doesn't matter.
+      if (!isa<StringLiteral>(Bop->getLHS()->IgnoreParenImpCasts()))
         return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop);
     } else if (Bop->getOpcode() == BO_LOr) {
       if (BinaryOperator *RBop = dyn_cast<BinaryOperator>(Bop->getRHS())) {
-        // If it's "a || b && 1 || c" we didn't warn earlier for
-        // "a || b && 1", but warn now.
-        if (RBop->getOpcode() == BO_LAnd && EvaluatesAsTrue(S, RBop->getRHS()))
+        // If it's "a || b && string_literal || c" we didn't warn earlier for
+        // "a || b && string_literal", but warn now.
+        if (RBop->getOpcode() == BO_LAnd &&
+            isa<StringLiteral>(RBop->getRHS()->IgnoreParenImpCasts()))
           return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, RBop);
       }
     }
@@ -15477,11 +15460,9 @@
                                              Expr *LHSExpr, Expr *RHSExpr) {
   if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(RHSExpr)) {
     if (Bop->getOpcode() == BO_LAnd) {
-      // If it's "0 || a && b" don't warn since the precedence doesn't matter.
-      if (EvaluatesAsFalse(S, LHSExpr))
-        return;
-      // If it's "a || b && 1" don't warn since the precedence doesn't matter.
-      if (!EvaluatesAsTrue(S, Bop->getRHS()))
+      // If it's "a || b && string_literal" don't warn since the precedence
+      // doesn't matter.
+      if (!isa<StringLiteral>(Bop->getRHS()->IgnoreParenImpCasts()))
         return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop);
     }
   }
Index: clang/test/Sema/logical-op-parentheses.c
===================================================================
--- clang/test/Sema/logical-op-parentheses.c
+++ clang/test/Sema/logical-op-parentheses.c
@@ -8,6 +8,7 @@
 #endif
 
 void logical_op_parentheses(unsigned i) {
+	const unsigned t = 1;
   (void)(i ||
              i && i);
 #ifndef SILENCE
@@ -17,8 +18,55 @@
   // CHECK: fix-it:"{{.*}}":{[[@LINE-5]]:14-[[@LINE-5]]:14}:"("
   // CHECK: fix-it:"{{.*}}":{[[@LINE-6]]:20-[[@LINE-6]]:20}:")"
 
-  (void)(i || i && "w00t");
+  (void)(t ||
+             t && t);
+#ifndef SILENCE
+  // expected-warning@-2 {{'&&' within '||'}}
+  // expected-note@-3 {{place parentheses around the '&&' expression to silence this warning}}
+#endif
+  // CHECK: fix-it:"{{.*}}":{[[@LINE-5]]:14-[[@LINE-5]]:14}:"("
+  // CHECK: fix-it:"{{.*}}":{[[@LINE-6]]:20-[[@LINE-6]]:20}:")"
+
+  (void)(t && 
+             t || t);
+#ifndef SILENCE
+  // expected-warning@-3 {{'&&' within '||'}}
+  // expected-note@-4 {{place parentheses around the '&&' expression to silence this warning}}
+#endif
+  // CHECK: fix-it:"{{.*}}":{[[@LINE-6]]:10-[[@LINE-6]]:10}:"("
+  // CHECK: fix-it:"{{.*}}":{[[@LINE-6]]:15-[[@LINE-6]]:15}:")"
+	
+	(void)(i || i && "w00t");
   (void)("w00t" && i || i);
+  (void)("w00t" && t || t);
+  (void)(t && t || 0);
+#ifndef SILENCE
+  // expected-warning@-2 {{'&&' within '||'}}
+  // expected-note@-3 {{place parentheses around the '&&' expression to silence this warning}}
+#endif
+  // CHECK: fix-it:"{{.*}}":{[[@LINE-5]]:10-[[@LINE-5]]:10}:"("
+  // CHECK: fix-it:"{{.*}}":{[[@LINE-6]]:16-[[@LINE-6]]:16}:")"
+  (void)(1 && t || t);
+#ifndef SILENCE
+  // expected-warning@-2 {{'&&' within '||'}}
+  // expected-note@-3 {{place parentheses around the '&&' expression to silence this warning}}
+#endif
+  // CHECK: fix-it:"{{.*}}":{[[@LINE-5]]:10-[[@LINE-5]]:10}:"("
+  // CHECK: fix-it:"{{.*}}":{[[@LINE-6]]:16-[[@LINE-6]]:16}:")"
+  (void)(0 || t && t);
+#ifndef SILENCE
+  // expected-warning@-2 {{'&&' within '||'}}
+  // expected-note@-3 {{place parentheses around the '&&' expression to silence this warning}}
+#endif
+  // CHECK: fix-it:"{{.*}}":{[[@LINE-5]]:15-[[@LINE-5]]:15}:"("
+  // CHECK: fix-it:"{{.*}}":{[[@LINE-6]]:21-[[@LINE-6]]:21}:")"
+  (void)(t || t && 1);
+#ifndef SILENCE
+  // expected-warning@-2 {{'&&' within '||'}}
+  // expected-note@-3 {{place parentheses around the '&&' expression to silence this warning}}
+#endif
+  // CHECK: fix-it:"{{.*}}":{[[@LINE-5]]:15-[[@LINE-5]]:15}:"("
+  // CHECK: fix-it:"{{.*}}":{[[@LINE-6]]:21-[[@LINE-6]]:21}:")"
 
   (void)(i || i && "w00t" || i);
 #ifndef SILENCE
@@ -37,5 +85,17 @@
   // CHECK: fix-it:"{{.*}}":{[[@LINE-6]]:26-[[@LINE-6]]:26}:")"
 
   (void)(i && i || 0);
+#ifndef SILENCE
+  // expected-warning@-2 {{'&&' within '||'}}
+  // expected-note@-3 {{place parentheses around the '&&' expression to silence this warning}}
+#endif
+  // CHECK: fix-it:"{{.*}}":{[[@LINE-5]]:10-[[@LINE-5]]:10}:"("
+  // CHECK: fix-it:"{{.*}}":{[[@LINE-6]]:16-[[@LINE-6]]:16}:")"
   (void)(0 || i && i);
+#ifndef SILENCE
+  // expected-warning@-2 {{'&&' within '||'}}
+  // expected-note@-3 {{place parentheses around the '&&' expression to silence this warning}}
+#endif
+  // CHECK: fix-it:"{{.*}}":{[[@LINE-5]]:15-[[@LINE-5]]:15}:"("
+  // CHECK: fix-it:"{{.*}}":{[[@LINE-6]]:21-[[@LINE-6]]:21}:")"
 }