From 35532cf0a9cc855fe5f0a4eefd4c343687a595dc Mon Sep 17 00:00:00 2001
From: Ming-Yi Lai <ming-yi.lai@mediatek.com>
Date: Fri, 10 May 2024 14:16:59 +0800
Subject: [PATCH] [clang][RISCV] Add Zicfilp CFI scheme preprocessor macros

These macros allow assembly files to know which CFI label to use when the target
has Zicfilp enabled.
---
 clang/lib/Basic/Targets/RISCV.cpp             | 19 +++++
 .../test/CodeGen/RISCV/riscv-cf-protection.c  | 79 +++++++++++++++++++
 2 files changed, 98 insertions(+)

diff --git a/clang/lib/Basic/Targets/RISCV.cpp b/clang/lib/Basic/Targets/RISCV.cpp
index b6ea4440507ea1..b9199e3bc77d34 100644
--- a/clang/lib/Basic/Targets/RISCV.cpp
+++ b/clang/lib/Basic/Targets/RISCV.cpp
@@ -224,6 +224,25 @@ void RISCVTargetInfo::getTargetDefines(const LangOptions &Opts,
     else
       Builder.defineMacro("__riscv_32e");
   }
+
+  if (Opts.CFProtectionBranch) {
+    auto Scheme = Opts.getCFBranchLabelScheme();
+    if (Scheme == CFBranchLabelSchemeKind::Default)
+      Scheme = getDefaultCFBranchLabelScheme();
+
+    Builder.defineMacro("__riscv_landing_pad", "1");
+    switch (Scheme) {
+    case CFBranchLabelSchemeKind::Unlabeled:
+      Builder.defineMacro("__riscv_landing_pad_unlabeled", "1");
+      break;
+    case CFBranchLabelSchemeKind::FuncSig:
+      Builder.defineMacro("__riscv_landing_pad_func_sig", "1");
+      break;
+    case CFBranchLabelSchemeKind::Default:
+      llvm_unreachable("default cf-branch-label scheme should already be "
+                       "transformed to other scheme");
+    }
+  }
 }
 
 static constexpr Builtin::Info BuiltinInfo[] = {
diff --git a/clang/test/CodeGen/RISCV/riscv-cf-protection.c b/clang/test/CodeGen/RISCV/riscv-cf-protection.c
index 3a9855a3d2f011..db7b65061658c0 100644
--- a/clang/test/CodeGen/RISCV/riscv-cf-protection.c
+++ b/clang/test/CodeGen/RISCV/riscv-cf-protection.c
@@ -1,71 +1,143 @@
+// RUN: %clang --target=riscv32 -menable-experimental-extensions \
+// RUN: -march=rv32i_zicfilp1p0 -fcf-protection=branch \
+// RUN: -mcf-branch-label-scheme=unlabeled -E -dM %s -o - | FileCheck \
+// RUN: --check-prefixes=LPAD-MACRO,UNLABELED-MACRO %s
+
 // RUN: %clang --target=riscv32 -menable-experimental-extensions \
 // RUN: -march=rv32i_zicfilp1p0 -fcf-protection=branch \
 // RUN: -mcf-branch-label-scheme=unlabeled -S -emit-llvm %s -o - | FileCheck \
 // RUN: --check-prefixes=BRANCH-PROT-FLAG,UNLABELED-FLAG %s
 
+// RUN: %clang --target=riscv32 -menable-experimental-extensions \
+// RUN: -march=rv32i_zicfilp1p0 -fcf-protection=branch \
+// RUN: -mcf-branch-label-scheme=func-sig -E -dM %s -o - | FileCheck \
+// RUN: --check-prefixes=LPAD-MACRO,FUNC-SIG-MACRO %s
+
 // RUN: %clang --target=riscv32 -menable-experimental-extensions \
 // RUN: -march=rv32i_zicfilp1p0 -fcf-protection=branch \
 // RUN: -mcf-branch-label-scheme=func-sig -S -emit-llvm %s -o - | FileCheck \
 // RUN: --check-prefixes=BRANCH-PROT-FLAG,FUNC-SIG-FLAG %s
 
+// RUN: %clang --target=riscv32 -menable-experimental-extensions \
+// RUN: -march=rv32i_zicfilp1p0 -mcf-branch-label-scheme=unlabeled -E -dM %s \
+// RUN: -o - 2>&1 | FileCheck \
+// RUN: --check-prefixes=NO-MACRO,UNLABELED-SCHEME-UNUSED %s
+
 // RUN: %clang --target=riscv32 -menable-experimental-extensions \
 // RUN: -march=rv32i_zicfilp1p0 -mcf-branch-label-scheme=unlabeled -S \
 // RUN: -emit-llvm %s -o - 2>&1 | FileCheck \
 // RUN: --check-prefixes=NO-FLAG,UNLABELED-SCHEME-UNUSED %s
 
+// RUN: %clang --target=riscv32 -menable-experimental-extensions \
+// RUN: -march=rv32i_zicfilp1p0 -mcf-branch-label-scheme=func-sig -E -dM %s \
+// RUN: -o - 2>&1 | FileCheck \
+// RUN: --check-prefixes=NO-MACRO,FUNC-SIG-SCHEME-UNUSED %s
+
 // RUN: %clang --target=riscv32 -menable-experimental-extensions \
 // RUN: -march=rv32i_zicfilp1p0 -mcf-branch-label-scheme=func-sig -S \
 // RUN: -emit-llvm %s -o - 2>&1 | FileCheck \
 // RUN: --check-prefixes=NO-FLAG,FUNC-SIG-SCHEME-UNUSED %s
 
+// RUN: %clang --target=riscv32 -fcf-protection=branch \
+// RUN: -mcf-branch-label-scheme=unlabeled -E -dM -emit-llvm %s -o - | \
+// RUN: FileCheck --check-prefixes=LPAD-MACRO,UNLABELED-MACRO %s
+
 // RUN: %clang --target=riscv32 -fcf-protection=branch \
 // RUN: -mcf-branch-label-scheme=unlabeled -S -emit-llvm %s -o - | FileCheck \
 // RUN: --check-prefixes=BRANCH-PROT-FLAG,UNLABELED-FLAG %s
 
+// RUN: %clang --target=riscv32 -fcf-protection=branch \
+// RUN: -mcf-branch-label-scheme=func-sig -E -dM %s -o - | FileCheck \
+// RUN: --check-prefixes=LPAD-MACRO,FUNC-SIG-MACRO %s
+
 // RUN: %clang --target=riscv32 -fcf-protection=branch \
 // RUN: -mcf-branch-label-scheme=func-sig -S -emit-llvm %s -o - | FileCheck \
 // RUN: --check-prefixes=BRANCH-PROT-FLAG,FUNC-SIG-FLAG %s
 
+// RUN: %clang --target=riscv32 -mcf-branch-label-scheme=unlabeled -E -dM %s \
+// RUN: -o - 2>&1 | FileCheck \
+// RUN: --check-prefixes=NO-MACRO,UNLABELED-SCHEME-UNUSED %s
+
 // RUN: %clang --target=riscv32 -mcf-branch-label-scheme=unlabeled -S \
 // RUN: -emit-llvm %s -o - 2>&1 | FileCheck \
 // RUN: --check-prefixes=NO-FLAG,UNLABELED-SCHEME-UNUSED %s
 
+// RUN: %clang --target=riscv32 -mcf-branch-label-scheme=func-sig -E -dM %s \
+// RUN: -o - 2>&1 | FileCheck \
+// RUN: --check-prefixes=NO-MACRO,FUNC-SIG-SCHEME-UNUSED %s
+
 // RUN: %clang --target=riscv32 -mcf-branch-label-scheme=func-sig -S \
 // RUN: -emit-llvm %s -o - 2>&1 | FileCheck \
 // RUN: --check-prefixes=NO-FLAG,FUNC-SIG-SCHEME-UNUSED %s
 
+// RUN: %clang --target=riscv64 -menable-experimental-extensions \
+// RUN: -march=rv64i_zicfilp1p0 -fcf-protection=branch \
+// RUN: -mcf-branch-label-scheme=unlabeled -E -dM %s -o - | FileCheck \
+// RUN: --check-prefixes=LPAD-MACRO,UNLABELED-MACRO %s
+
 // RUN: %clang --target=riscv64 -menable-experimental-extensions \
 // RUN: -march=rv64i_zicfilp1p0 -fcf-protection=branch \
 // RUN: -mcf-branch-label-scheme=unlabeled -S -emit-llvm %s -o - | FileCheck \
 // RUN: --check-prefixes=BRANCH-PROT-FLAG,UNLABELED-FLAG %s
 
+// RUN: %clang --target=riscv64 -menable-experimental-extensions \
+// RUN: -march=rv64i_zicfilp1p0 -fcf-protection=branch \
+// RUN: -mcf-branch-label-scheme=func-sig -E -dM %s -o - | FileCheck \
+// RUN: --check-prefixes=LPAD-MACRO,FUNC-SIG-MACRO %s
+
 // RUN: %clang --target=riscv64 -menable-experimental-extensions \
 // RUN: -march=rv64i_zicfilp1p0 -fcf-protection=branch \
 // RUN: -mcf-branch-label-scheme=func-sig -S -emit-llvm %s -o - | FileCheck \
 // RUN: --check-prefixes=BRANCH-PROT-FLAG,FUNC-SIG-FLAG %s
 
+// RUN: %clang --target=riscv64 -menable-experimental-extensions \
+// RUN: -march=rv64i_zicfilp1p0 -mcf-branch-label-scheme=unlabeled -E -dM %s \
+// RUN: -o - 2>&1 | FileCheck \
+// RUN: --check-prefixes=NO-MACRO,UNLABELED-SCHEME-UNUSED %s
+
 // RUN: %clang --target=riscv64 -menable-experimental-extensions \
 // RUN: -march=rv64i_zicfilp1p0 -mcf-branch-label-scheme=unlabeled -S \
 // RUN: -emit-llvm %s -o - 2>&1 | FileCheck \
 // RUN: --check-prefixes=NO-FLAG,UNLABELED-SCHEME-UNUSED %s
 
+// RUN: %clang --target=riscv64 -menable-experimental-extensions \
+// RUN: -march=rv64i_zicfilp1p0 -mcf-branch-label-scheme=func-sig -E -dM %s \
+// RUN: -o - 2>&1 | FileCheck \
+// RUN: --check-prefixes=NO-MACRO,FUNC-SIG-SCHEME-UNUSED %s
+
 // RUN: %clang --target=riscv64 -menable-experimental-extensions \
 // RUN: -march=rv64i_zicfilp1p0 -mcf-branch-label-scheme=func-sig -S \
 // RUN: -emit-llvm %s -o - 2>&1 | FileCheck \
 // RUN: --check-prefixes=NO-FLAG,FUNC-SIG-SCHEME-UNUSED %s
 
+// RUN: %clang --target=riscv64 -fcf-protection=branch \
+// RUN: -mcf-branch-label-scheme=unlabeled -E -dM %s -o - | FileCheck \
+// RUN: --check-prefixes=LPAD-MACRO,UNLABELED-MACRO %s
+
 // RUN: %clang --target=riscv64 -fcf-protection=branch \
 // RUN: -mcf-branch-label-scheme=unlabeled -S -emit-llvm %s -o - | FileCheck \
 // RUN: --check-prefixes=BRANCH-PROT-FLAG,UNLABELED-FLAG %s
 
+// RUN: %clang --target=riscv64 -fcf-protection=branch \
+// RUN: -mcf-branch-label-scheme=func-sig -E -dM %s -o - | FileCheck \
+// RUN: --check-prefixes=LPAD-MACRO,FUNC-SIG-MACRO %s
+
 // RUN: %clang --target=riscv64 -fcf-protection=branch \
 // RUN: -mcf-branch-label-scheme=func-sig -S -emit-llvm %s -o - | FileCheck \
 // RUN: --check-prefixes=BRANCH-PROT-FLAG,FUNC-SIG-FLAG %s
 
+// RUN: %clang --target=riscv64 -mcf-branch-label-scheme=unlabeled -E -dM %s \
+// RUN: -o - 2>&1 | FileCheck \
+// RUN: --check-prefixes=NO-MACRO,UNLABELED-SCHEME-UNUSED %s
+
 // RUN: %clang --target=riscv64 -mcf-branch-label-scheme=unlabeled -S \
 // RUN: -emit-llvm %s -o - 2>&1 | FileCheck \
 // RUN: --check-prefixes=NO-FLAG,UNLABELED-SCHEME-UNUSED %s
 
+// RUN: %clang --target=riscv64 -mcf-branch-label-scheme=func-sig -E -dM %s \
+// RUN: -o - 2>&1 | FileCheck \
+// RUN: --check-prefixes=NO-MACRO,FUNC-SIG-SCHEME-UNUSED %s
+
 // RUN: %clang --target=riscv64 -mcf-branch-label-scheme=func-sig -S \
 // RUN: -emit-llvm %s -o - 2>&1 | FileCheck \
 // RUN: --check-prefixes=NO-FLAG,FUNC-SIG-SCHEME-UNUSED %s
@@ -83,6 +155,13 @@
 // FUNC-SIG-SCHEME-UNUSED: warning: argument unused during compilation:
 // FUNC-SIG-SCHEME-UNUSED-SAME: '-mcf-branch-label-scheme=func-sig'
 
+// LPAD-MACRO: __riscv_landing_pad 1{{$}}
+// UNLABELED-MACRO: __riscv_landing_pad_unlabeled 1{{$}}
+// FUNC-SIG-MACRO: __riscv_landing_pad_func_sig 1{{$}}
+// NO-MACRO-NOT: __riscv_landing_pad
+// NO-MACRO-NOT: __riscv_landing_pad_unlabeled
+// NO-MACRO-NOT: __riscv_landing_pad_func_sig
+
 // BRANCH-PROT-FLAG-DAG: [[P_FLAG:![0-9]+]] = !{i32 8, !"cf-protection-branch", i32 1}
 // UNLABELED-FLAG-DAG: [[S_FLAG:![0-9]+]] = !{i32 1, !"cf-branch-label-scheme", !"unlabeled"}
 // FUNC-SIG-FLAG-DAG: [[S_FLAG:![0-9]+]] = !{i32 1, !"cf-branch-label-scheme", !"func-sig"}