0054-Xtensa-Correct-Call-ABI-for-function-return.patch

From 0fb69a96de2843ce5a72a9a82a5e3d183ee168ec Mon Sep 17 00:00:00 2001
From: Andrei Safronov <safronov@espressif.com>
Date: Wed, 5 Apr 2023 00:59:05 +0300
Subject: [PATCH 054/158] [Xtensa] Correct Call ABI for function return

 arguments.
---
 clang/lib/CodeGen/TargetInfo.cpp | 12 +++++++++---
 clang/test/CodeGen/xtensa-abi.c  | 14 ++++++++++++++
 2 files changed, 23 insertions(+), 3 deletions(-)
 create mode 100644 clang/test/CodeGen/xtensa-abi.c

diff --git a/clang/lib/CodeGen/TargetInfo.cpp b/clang/lib/CodeGen/TargetInfo.cpp
index f595ce2c4b15..4ef05b97c06b 100644
--- a/clang/lib/CodeGen/TargetInfo.cpp
+++ b/clang/lib/CodeGen/TargetInfo.cpp
@@ -12287,10 +12287,16 @@ ABIArgInfo XtensaABIInfo::classifyArgumentType(QualType Ty,
 ABIArgInfo XtensaABIInfo::classifyReturnType(QualType RetTy) const {
   if (RetTy->isVoidType())
     return ABIArgInfo::getIgnore();
+
   int ArgGPRsLeft = MaxNumRetGPRs;
-  // The rules for return and argument types are the same, so defer to
-  // classifyArgumentType.
-  return classifyArgumentType(RetTy, ArgGPRsLeft);
+  auto RetSize = llvm::alignTo(getContext().getTypeSize(RetTy), 32) / 32;
+
+  // The rules for return and argument with type size more then 4 bytes
+  // are the same, so defer to classifyArgumentType.
+  if (RetSize > 1)
+    return classifyArgumentType(RetTy, ArgGPRsLeft);
+
+  return DefaultABIInfo::classifyReturnType(RetTy);
 }
 
 Address XtensaABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
diff --git a/clang/test/CodeGen/xtensa-abi.c b/clang/test/CodeGen/xtensa-abi.c
new file mode 100644
index 000000000000..4ce59e8466c8
--- /dev/null
+++ b/clang/test/CodeGen/xtensa-abi.c
@@ -0,0 +1,14 @@
+// RUN: %clang_cc1 -no-opaque-pointers -triple xtensa -O0 -emit-llvm %s -o - | FileCheck %s
+
+#define	__malloc_like	__attribute__((__malloc__))
+char *bufalloc () __malloc_like ;//__result_use_check;
+extern void* malloc (unsigned size);
+
+char *bufalloc ()
+{
+  char* buf = malloc(1024);
+
+  return buf;
+}
+
+// CHECK: define dso_local noalias i8* @bufalloc() #0 {
-- 
2.40.1