1 files changed, 39 insertions, 0 deletions
diff --git a/llvm/test/Transforms/Inline/call-intrinsic-is-constant.ll b/llvm/test/Transforms/Inline/call-intrinsic-is-constant.ll
new file mode 100644
index 0000000..3c96267
--- /dev/null
+++ b/llvm/test/Transforms/Inline/call-intrinsic-is-constant.ll
@@ -0,0 +1,39 @@
+; RUN: opt %s -passes=inline -inline-threshold=20 -S | FileCheck %s
+
+declare i1 @llvm.is.constant.i64(i64)
+declare void @foo()
+
+define void @callee(i64 %val) {
+  %cond = call i1 @llvm.is.constant.i64(i64 %val)
+  br i1 %cond, label %cond.true, label %cond.false
+
+cond.true:
+; Rack up costs with a couple of function calls so that this function
+; gets inlined only when @llvm.is.constant.i64 is folded.  In reality,
+; the "then" clause of __builtin_constant_p tends to have statements
+; that fold very well, so the cost of the "then" clause is not a huge
+; concern.
+  call void @foo()
+  call void @foo()
+  ret void
+
+cond.false:
+  ret void
+}
+
+define void @caller(i64 %val) {
+; CHECK-LABEL: @caller(
+; CHECK-NEXT:    [[COND_I:%.*]] = call i1 @llvm.is.constant.i64(i64 [[VAL:%.*]])
+; CHECK-NEXT:    br i1 [[COND_I]], label %[[COND_TRUE_I:.*]], label %[[COND_FALSE_I:.*]]
+; CHECK:       [[COND_TRUE_I]]:
+; CHECK-NEXT:    call void @foo()
+; CHECK-NEXT:    call void @foo()
+; CHECK-NEXT:    br label %[[CALLEE_EXIT:.*]]
+; CHECK:       [[COND_FALSE_I]]:
+; CHECK-NEXT:    br label %[[CALLEE_EXIT]]
+; CHECK:       [[CALLEE_EXIT]]:
+; CHECK-NEXT:    ret void
+;
+  call void @callee(i64 %val)
+  ret void
+}