1 files changed, 26 insertions, 0 deletions
diff --git a/test/CodeGen/AArch64/arm64-platform-reg.ll b/test/CodeGen/AArch64/arm64-platform-reg.ll
new file mode 100644
index 0000000..651c793
--- /dev/null
+++ b/test/CodeGen/AArch64/arm64-platform-reg.ll
@@ -0,0 +1,26 @@
+; RUN: llc -mtriple=arm64-apple-ios -o - %s | FileCheck %s --check-prefix=CHECK-DARWIN
+; RUN: llc -mtriple=arm64-linux-gnu -o - %s | FileCheck %s
+
+; x18 is reserved as a platform register on Darwin but not on other
+; systems. Create loads of register pressure and make sure this is respected.
+
+; Also, fp must always refer to a valid frame record, even if it's not the one
+; of the current function, so it shouldn't be used either.
+
+@var = global [30 x i64] zeroinitializer
+
+define void @keep_live() {
+  %val = load volatile [30 x i64]* @var
+  store volatile [30 x i64] %val, [30 x i64]* @var
+
+; CHECK: ldr x18
+; CHECK: str x18
+
+; CHECK-DARWIN-NOT: ldr fp
+; CHECK-DARWIN-NOT: ldr x18
+; CHECK-DARWIN: Spill
+; CHECK-DARWIN-NOT: ldr fp
+; CHECK-DARWIN-NOT: ldr x18
+; CHECK-DARWIN: ret
+  ret void
+}