diff --git a/llvm/lib/Transforms/IPO/InferFunctionAttrs.cpp b/llvm/lib/Transforms/IPO/InferFunctionAttrs.cpp
--- a/llvm/lib/Transforms/IPO/InferFunctionAttrs.cpp
+++ b/llvm/lib/Transforms/IPO/InferFunctionAttrs.cpp
@@ -19,6 +19,41 @@
 
 #define DEBUG_TYPE "inferattrs"
 
+/// If we can infer one attribute from another on the declaration of a
+/// function, explicitly materialize the maximal set for readability in the IR.
+/// Doing this also allows our CGSCC inference to avoid needing to duplicate
+/// this logic on all calls to declarations (as declarations aren't explicitly
+/// visited by CGSCC passes in the new pass manager.)
+static bool inferAttributesFromOthers(Function &F) {
+  // Note: We explicitly check for attributes rather than using cover functions
+  // because some of the cover functions include the logic being implemented.
+
+  bool Changed = false;
+  // readnone + not convergent implies nosync
+  if (!F.hasFnAttribute(Attribute::NoSync) &&
+      F.doesNotAccessMemory() && !F.isConvergent()) {
+    F.setNoSync();
+    Changed = true;
+  }
+
+  // readonly implies nofree
+  if (!F.hasFnAttribute(Attribute::NoFree) && F.onlyReadsMemory()) {
+    F.setDoesNotFreeMemory();
+    Changed = true;
+  }
+
+  // willreturn implies mustprogress
+  if (!F.hasFnAttribute(Attribute::MustProgress) && F.willReturn()) {
+    F.setMustProgress();
+    Changed = true;
+  }
+
+  // TODO: There are a bunch of cases of restrictive memory effects we
+  // can infer by inspecting arguments of argmemonly-ish functions.
+
+  return Changed;
+}
+
 static bool inferAllPrototypeAttributes(
     Module &M, function_ref<TargetLibraryInfo &(Function &)> GetTLI) {
   bool Changed = false;
@@ -26,8 +61,10 @@
   for (Function &F : M.functions())
     // We only infer things using the prototype and the name; we don't need
     // definitions.
-    if (F.isDeclaration() && !F.hasOptNone())
+    if (F.isDeclaration() && !F.hasOptNone()) {
       Changed |= inferLibFuncAttributes(F, GetTLI(F));
+      Changed |= inferAttributesFromOthers(F);
+    }
 
   return Changed;
 }
diff --git a/llvm/test/Other/cgscc-devirt-iteration.ll b/llvm/test/Other/cgscc-devirt-iteration.ll
--- a/llvm/test/Other/cgscc-devirt-iteration.ll
+++ b/llvm/test/Other/cgscc-devirt-iteration.ll
@@ -4,18 +4,18 @@
 ; devirtualization here with GVN which forwards a store through a load and to
 ; an indirect call.
 ;
-; RUN: opt -aa-pipeline=basic-aa -passes='cgscc(function-attrs,function(gvn,instcombine))' -S < %s | FileCheck %s --check-prefix=CHECK --check-prefix=BEFORE
-; RUN: opt -aa-pipeline=basic-aa -passes='cgscc(devirt<1>(function-attrs,function(gvn,instcombine)))' -S < %s | FileCheck %s --check-prefix=CHECK --check-prefix=AFTER --check-prefix=AFTER1
-; RUN: opt -aa-pipeline=basic-aa -passes='cgscc(devirt<2>(function-attrs,function(gvn,instcombine)))' -S < %s | FileCheck %s --check-prefix=CHECK --check-prefix=AFTER --check-prefix=AFTER2
+; RUN: opt -aa-pipeline=basic-aa -passes='module(inferattrs),cgscc(function-attrs,function(gvn,instcombine))' -S < %s | FileCheck %s --check-prefix=CHECK --check-prefix=BEFORE
+; RUN: opt -aa-pipeline=basic-aa -passes='module(inferattrs),cgscc(devirt<1>(function-attrs,function(gvn,instcombine)))' -S < %s | FileCheck %s --check-prefix=CHECK --check-prefix=AFTER --check-prefix=AFTER1
+; RUN: opt -aa-pipeline=basic-aa -passes='module(inferattrs),cgscc(devirt<2>(function-attrs,function(gvn,instcombine)))' -S < %s | FileCheck %s --check-prefix=CHECK --check-prefix=AFTER --check-prefix=AFTER2
 ;
-; RUN: not --crash opt -abort-on-max-devirt-iterations-reached -aa-pipeline=basic-aa -passes='cgscc(devirt<1>(function-attrs,function(gvn,instcombine)))' -S < %s
-; RUN: opt -abort-on-max-devirt-iterations-reached -aa-pipeline=basic-aa -passes='cgscc(devirt<2>(function-attrs,function(gvn,instcombine)))' -S < %s
+; RUN: not --crash opt -abort-on-max-devirt-iterations-reached -aa-pipeline=basic-aa -passes='module(inferattrs),cgscc(devirt<1>(function-attrs,function(gvn,instcombine)))' -S < %s
+; RUN: opt -abort-on-max-devirt-iterations-reached -aa-pipeline=basic-aa -passes='module(inferattrs),cgscc(devirt<2>(function-attrs,function(gvn,instcombine)))' -S < %s
 ;
 ; We also verify that the real O2 pipeline catches these cases.
 ; RUN: opt -aa-pipeline=basic-aa -passes='default<O2>' -S < %s | FileCheck %s --check-prefix=CHECK --check-prefix=AFTER --check-prefix=AFTER2
 
 declare void @readnone() readnone
-; CHECK: Function Attrs: readnone
+; CHECK: Function Attrs: nofree nosync readnone
 ; CHECK-NEXT: declare void @readnone()
 
 declare void @unknown()
@@ -51,7 +51,7 @@
 ; devirtualize again, and then deduce readnone.
 
 declare void @readnone_with_arg(void ()**) readnone
-; CHECK: Function Attrs: readnone
+; CHECK: Function Attrs: nofree nosync readnone
 ; CHECK-LABEL: declare void @readnone_with_arg(void ()**)
 
 define void @test2_a(void ()** %ignore) {
diff --git a/llvm/test/Transforms/InferFunctionAttrs/annotate.ll b/llvm/test/Transforms/InferFunctionAttrs/annotate.ll
--- a/llvm/test/Transforms/InferFunctionAttrs/annotate.ll
+++ b/llvm/test/Transforms/InferFunctionAttrs/annotate.ll
@@ -1016,18 +1016,18 @@
 declare void @memset_pattern16(i8*, i8*, i64)
 
 
-; CHECK-DAG: attributes [[NOFREE_NOUNWIND_WILLRETURN]] = { nofree nounwind willreturn }
+; CHECK-DAG: attributes [[NOFREE_NOUNWIND_WILLRETURN]] = { nofree nounwind willreturn mustprogress }
 ; CHECK-DAG: attributes [[NOFREE_NOUNWIND]] = { nofree nounwind }
-; CHECK-DAG: attributes [[INACCESSIBLEMEMONLY_NOFREE_NOUNWIND_WILLRETURN]] = { inaccessiblememonly nofree nounwind willreturn }
-; CHECK-DAG: attributes [[NOFREE_NOUNWIND_READONLY_WILLRETURN]] = { nofree nounwind readonly willreturn }
-; CHECK-DAG: attributes [[ARGMEMONLY_NOFREE_NOUNWIND_WILLRETURN]] = { argmemonly nofree nounwind willreturn }
+; CHECK-DAG: attributes [[INACCESSIBLEMEMONLY_NOFREE_NOUNWIND_WILLRETURN]] = { inaccessiblememonly nofree nounwind willreturn mustprogress }
+; CHECK-DAG: attributes [[NOFREE_NOUNWIND_READONLY_WILLRETURN]] = { nofree nounwind readonly willreturn mustprogress }
+; CHECK-DAG: attributes [[ARGMEMONLY_NOFREE_NOUNWIND_WILLRETURN]] = { argmemonly nofree nounwind willreturn mustprogress }
 ; CHECK-DAG: attributes [[NOFREE_NOUNWIND_READONLY]] = { nofree nounwind readonly }
-; CHECK-DAG: attributes [[INACCESSIBLEMEMORARGMEMONLY_NOUNWIND_WILLRETURN]] = { inaccessiblemem_or_argmemonly nounwind willreturn }
-; CHECK-DAG: attributes [[NOFREE_WILLRETURN]] = { nofree willreturn }
-; CHECK-DAG: attributes [[ARGMEMONLY_NOFREE_NOUNWIND_READONLY_WILLRETURN]] = { argmemonly nofree nounwind readonly willreturn }
+; CHECK-DAG: attributes [[INACCESSIBLEMEMORARGMEMONLY_NOUNWIND_WILLRETURN]] = { inaccessiblemem_or_argmemonly nounwind willreturn mustprogress }
+; CHECK-DAG: attributes [[NOFREE_WILLRETURN]] = { nofree willreturn mustprogress }
+; CHECK-DAG: attributes [[ARGMEMONLY_NOFREE_NOUNWIND_READONLY_WILLRETURN]] = { argmemonly nofree nounwind readonly willreturn mustprogress }
 ; CHECK-DAG: attributes [[NOFREE]] = { nofree }
-; CHECK-DAG: attributes [[WILLRETURN]] = { willreturn }
-; CHECK-DAG: attributes [[INACCESSIBLEMEMORARGONLY_NOFREE_NOUNWIND_WILLRETURN]]  = { inaccessiblemem_or_argmemonly nofree nounwind willreturn }
+; CHECK-DAG: attributes [[WILLRETURN]] = { willreturn mustprogress }
+; CHECK-DAG: attributes [[INACCESSIBLEMEMORARGONLY_NOFREE_NOUNWIND_WILLRETURN]]  = { inaccessiblemem_or_argmemonly nofree nounwind willreturn mustprogress }
 
 ; CHECK-DARWIN-DAG: attributes [[ARGMEMONLY_NOFREE]] = { argmemonly nofree }
-; CHECK-NVPTX-DAG: attributes [[NOFREE_NOUNWIND_READNONE]] = { nofree nounwind readnone }
+; CHECK-NVPTX-DAG: attributes [[NOFREE_NOUNWIND_READNONE]] = { nofree nosync nounwind readnone }
diff --git a/llvm/test/Transforms/LICM/strlen.ll b/llvm/test/Transforms/LICM/strlen.ll
--- a/llvm/test/Transforms/LICM/strlen.ll
+++ b/llvm/test/Transforms/LICM/strlen.ll
@@ -13,7 +13,7 @@
 }
 
 ; CHECK: declare i64 @strlen(i8* nocapture) #0
-; CHECK: attributes #0 = { argmemonly nofree nounwind readonly willreturn }
+; CHECK: attributes #0 = { argmemonly nofree nounwind readonly willreturn mustprogress }
 declare i64 @strlen(i8*)