diff --git a/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp b/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp
--- a/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp
+++ b/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp
@@ -817,7 +817,18 @@
     bool IsRecursive = C.size() > 1;
     for (LazyCallGraph::Node &N : C) {
       Function &OldF = N.getFunction();
-      Function *NewF = promoteArguments(&OldF, FAM, MaxElements, IsRecursive);
+
+      // If the IR specifies a maximum element count via !argpromotion
+      // metadata, take that into account.
+      unsigned MaxElems = MaxElements;
+      if (MDNode *MD = OldF.getMetadata("argpromotion"))
+        MaxElems =
+            mdconst::extract<ConstantInt>(MD->getOperand(0))->getZExtValue();
+
+      if (MaxElems == 0)
+        continue;
+
+      Function *NewF = promoteArguments(&OldF, FAM, MaxElems, IsRecursive);
       if (!NewF)
         continue;
       LocalChange = true;
diff --git a/llvm/test/Transforms/ArgumentPromotion/arg-promotion-metadata.ll b/llvm/test/Transforms/ArgumentPromotion/arg-promotion-metadata.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/Transforms/ArgumentPromotion/arg-promotion-metadata.ll
@@ -0,0 +1,95 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; Tests that !argpromotion metadata allows the frontend to specify the maximum
+; number of elements we choose to split.
+; RUN: opt < %s -passes=argpromotion -S | FileCheck %S
+
+%struct.Foo = type { i32, i32, i32, i32 }
+
+@constant = private constant %struct.Foo { i32 1, i32 2, i32 3, i32 4 }, align 4
+
+; Argument promotion defaults to only promoting 2 elements; with no metadata
+; we won't promote anything.
+define internal void @no_metadata(ptr noundef dereferenceable(4) align 4 %0) {
+; CHECK-LABEL: @no_metadata(
+; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr inbounds [[STRUCT_FOO:%.*]], ptr [[TMP0:%.*]], i32 0, i32 0
+; CHECK-NEXT:    [[TMP3:%.*]] = load i32, ptr [[TMP2]], align 4
+; CHECK-NEXT:    [[TMP4:%.*]] = getelementptr inbounds [[STRUCT_FOO]], ptr [[TMP0]], i32 0, i32 1
+; CHECK-NEXT:    [[TMP5:%.*]] = load i32, ptr [[TMP4]], align 4
+; CHECK-NEXT:    [[TMP6:%.*]] = getelementptr inbounds [[STRUCT_FOO]], ptr [[TMP0]], i32 0, i32 2
+; CHECK-NEXT:    [[TMP7:%.*]] = load i32, ptr [[TMP6]], align 4
+; CHECK-NEXT:    [[TMP8:%.*]] = getelementptr inbounds [[STRUCT_FOO]], ptr [[TMP0]], i32 0, i32 3
+; CHECK-NEXT:    [[TMP9:%.*]] = load i32, ptr [[TMP8]], align 4
+; CHECK-NEXT:    ret void
+;
+  %2 = getelementptr inbounds %struct.Foo, ptr %0, i32 0, i32 0
+  %3 = load i32, ptr %2, align 4
+  %4 = getelementptr inbounds %struct.Foo, ptr %0, i32 0, i32 1
+  %5 = load i32, ptr %4, align 4
+  %6 = getelementptr inbounds %struct.Foo, ptr %0, i32 0, i32 2
+  %7 = load i32, ptr %6, align 4
+  %8 = getelementptr inbounds %struct.Foo, ptr %0, i32 0, i32 3
+  %9 = load i32, ptr %8, align 4
+  ret void
+}
+
+; When we override the maximum number of elements with metadata, we promote
+; arguments.
+define internal void @metadata_4(ptr noundef dereferenceable(4) align 4 %0) !argpromotion !{i64 4} {
+; CHECK-LABEL: @metadata_4(
+; CHECK-NEXT:    ret void
+;
+  %2 = getelementptr inbounds %struct.Foo, ptr %0, i32 0, i32 0
+  %3 = load i32, ptr %2, align 4
+  %4 = getelementptr inbounds %struct.Foo, ptr %0, i32 0, i32 1
+  %5 = load i32, ptr %4, align 4
+  %6 = getelementptr inbounds %struct.Foo, ptr %0, i32 0, i32 2
+  %7 = load i32, ptr %6, align 4
+  %8 = getelementptr inbounds %struct.Foo, ptr %0, i32 0, i32 3
+  %9 = load i32, ptr %8, align 4
+  ret void
+}
+
+; The metadata requested a maximum number of 3 elements, but we have 4, so
+; don't promote anything.
+define internal void @metadata_3(ptr noundef dereferenceable(4) align 4 %0) !argpromotion !{i64 3} {
+; CHECK-LABEL: @metadata_3(
+; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr inbounds [[STRUCT_FOO:%.*]], ptr [[TMP0:%.*]], i32 0, i32 0
+; CHECK-NEXT:    [[TMP3:%.*]] = load i32, ptr [[TMP2]], align 4
+; CHECK-NEXT:    [[TMP4:%.*]] = getelementptr inbounds [[STRUCT_FOO]], ptr [[TMP0]], i32 0, i32 1
+; CHECK-NEXT:    [[TMP5:%.*]] = load i32, ptr [[TMP4]], align 4
+; CHECK-NEXT:    [[TMP6:%.*]] = getelementptr inbounds [[STRUCT_FOO]], ptr [[TMP0]], i32 0, i32 2
+; CHECK-NEXT:    [[TMP7:%.*]] = load i32, ptr [[TMP6]], align 4
+; CHECK-NEXT:    [[TMP8:%.*]] = getelementptr inbounds [[STRUCT_FOO]], ptr [[TMP0]], i32 0, i32 3
+; CHECK-NEXT:    [[TMP9:%.*]] = load i32, ptr [[TMP8]], align 4
+; CHECK-NEXT:    ret void
+;
+  %2 = getelementptr inbounds %struct.Foo, ptr %0, i32 0, i32 0
+  %3 = load i32, ptr %2, align 4
+  %4 = getelementptr inbounds %struct.Foo, ptr %0, i32 0, i32 1
+  %5 = load i32, ptr %4, align 4
+  %6 = getelementptr inbounds %struct.Foo, ptr %0, i32 0, i32 2
+  %7 = load i32, ptr %6, align 4
+  %8 = getelementptr inbounds %struct.Foo, ptr %0, i32 0, i32 3
+  %9 = load i32, ptr %8, align 4
+  ret void
+}
+
+define i32 @main() {
+; CHECK-LABEL: @main(
+; CHECK-NEXT:    call void @no_metadata(ptr noundef align 4 dereferenceable(4) @constant)
+; CHECK-NEXT:    [[CONSTANT_VAL:%.*]] = load i32, ptr @constant, align 4
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i8, ptr @constant, i64 4
+; CHECK-NEXT:    [[CONSTANT_VAL1:%.*]] = load i32, ptr [[TMP1]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr i8, ptr @constant, i64 8
+; CHECK-NEXT:    [[CONSTANT_VAL2:%.*]] = load i32, ptr [[TMP2]], align 4
+; CHECK-NEXT:    [[TMP3:%.*]] = getelementptr i8, ptr @constant, i64 12
+; CHECK-NEXT:    [[CONSTANT_VAL3:%.*]] = load i32, ptr [[TMP3]], align 4
+; CHECK-NEXT:    call void @metadata_4(i32 [[CONSTANT_VAL]], i32 [[CONSTANT_VAL1]], i32 [[CONSTANT_VAL2]], i32 [[CONSTANT_VAL3]])
+; CHECK-NEXT:    call void @metadata_3(ptr noundef align 4 dereferenceable(4) @constant)
+; CHECK-NEXT:    ret i32 0
+;
+  call void @no_metadata(ptr noundef dereferenceable(4) align 4 @constant)
+  call void @metadata_4(ptr noundef dereferenceable(4) align 4 @constant)
+  call void @metadata_3(ptr noundef dereferenceable(4) align 4 @constant)
+  ret i32 0
+}