From 943837bfb6a867e0bd3ac18fdf4752b0b6fb5103 Mon Sep 17 00:00:00 2001 From: Renato Golin Date: Sun, 12 Jul 2015 18:16:40 +0000 Subject: [PATCH] [ARM] Add support for nest attribute using r12 Register r12 ('ip') is used by GCC for this purpose and hence is used here. As discussed on the GCC mailing list, the register choice is an ABI issue and so choosing the same register as GCC means __builtin_call_with_static_chain is compatible. A similar patch has just gone in the AArch64 backend, so this is just the ARM counterpart, following the same discussion. Patch by Stephen Cross. llvm-svn: 241996 --- lib/Target/ARM/ARMCallingConv.td | 3 +++ test/CodeGen/ARM/nest-register.ll | 21 +++++++++++++++++++++ 2 files changed, 24 insertions(+) create mode 100644 test/CodeGen/ARM/nest-register.ll diff --git a/lib/Target/ARM/ARMCallingConv.td b/lib/Target/ARM/ARMCallingConv.td index 7dd21ecbe91..27cf06b995a 100644 --- a/lib/Target/ARM/ARMCallingConv.td +++ b/lib/Target/ARM/ARMCallingConv.td @@ -142,6 +142,9 @@ def CC_ARM_AAPCS : CallingConv<[ // Handles byval parameters. CCIfByVal>, + // The 'nest' parameter, if any, is passed in R12. + CCIfNest>, + // Handle all vector types as either f64 or v2f64. CCIfType<[v1i64, v2i32, v4i16, v8i8, v2f32], CCBitConvertToType>, CCIfType<[v2i64, v4i32, v8i16, v16i8, v4f32], CCBitConvertToType>, diff --git a/test/CodeGen/ARM/nest-register.ll b/test/CodeGen/ARM/nest-register.ll new file mode 100644 index 00000000000..6b8c3dc47db --- /dev/null +++ b/test/CodeGen/ARM/nest-register.ll @@ -0,0 +1,21 @@ +; RUN: llc -mtriple=arm-eabi %s -o - | FileCheck %s + +; Tests that the 'nest' parameter attribute causes the relevant parameter to be +; passed in the right register. + +define i8* @nest_receiver(i8* nest %arg) nounwind { +; CHECK-LABEL: nest_receiver: +; CHECK: @ BB#0: +; CHECK-NEXT: mov r0, r12 +; CHECK-NEXT: mov pc, lr + ret i8* %arg +} + +define i8* @nest_caller(i8* %arg) nounwind { +; CHECK-LABEL: nest_caller: +; CHECK: mov r12, r0 +; CHECK-NEXT: bl nest_receiver +; CHECK: mov pc, lr + %result = call i8* @nest_receiver(i8* nest %arg) + ret i8* %result +}