[clang] [X86] Add ABI handling for fp128 (PR #75156)

[via cfe-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->
@llvm/pr-subscribers-clang-codegen

@llvm/pr-subscribers-backend-x86

Author: Phoebe Wang (phoebewang)

<details>
<summary>Changes</summary>

Fixes #<!-- -->74601

---
Full diff: https://github.com/llvm/llvm-project/pull/75156.diff


2 Files Affected:

- (modified) clang/lib/CodeGen/Targets/X86.cpp (+2-1) 
- (added) clang/test/CodeGen/X86/fp128-abi.c (+35) 


``````````diff
diff --git a/clang/lib/CodeGen/Targets/X86.cpp b/clang/lib/CodeGen/Targets/X86.cpp
index 2af24035043884..c4bf38056a673f 100644
--- a/clang/lib/CodeGen/Targets/X86.cpp
+++ b/clang/lib/CodeGen/Targets/X86.cpp
@@ -1795,7 +1795,8 @@ void X86_64ABIInfo::classify(QualType Ty, uint64_t OffsetBase, Class &Lo,
     } else if (k >= BuiltinType::Bool && k <= BuiltinType::LongLong) {
       Current = Integer;
     } else if (k == BuiltinType::Float || k == BuiltinType::Double ||
-               k == BuiltinType::Float16 || k == BuiltinType::BFloat16) {
+               k == BuiltinType::Float16 || k == BuiltinType::BFloat16 ||
+               k == BuiltinType::Float128) {
       Current = SSE;
     } else if (k == BuiltinType::LongDouble) {
       const llvm::fltSemantics *LDF = &getTarget().getLongDoubleFormat();
diff --git a/clang/test/CodeGen/X86/fp128-abi.c b/clang/test/CodeGen/X86/fp128-abi.c
new file mode 100644
index 00000000000000..1c5d7cf1166ee1
--- /dev/null
+++ b/clang/test/CodeGen/X86/fp128-abi.c
@@ -0,0 +1,35 @@
+// RUN: %clang_cc1 -triple x86_64-linux -emit-llvm  -target-feature +sse2 < %s | FileCheck %s --check-prefixes=CHECK
+
+struct st1 {
+  __float128 a;
+};
+
+struct st1 h1(__float128 a) {
+  // CHECK: define{{.*}}fp128 @h1(fp128
+  struct st1 x;
+  x.a = a;
+  return x;
+}
+
+__float128 h2(struct st1 x) {
+  // CHECK: define{{.*}}fp128 @h2(fp128
+  return x.a;
+}
+
+struct st2 {
+  __float128 a;
+  int b;
+};
+
+struct st2 h3(__float128 a, int b) {
+  // CHECK: define{{.*}}void @h3(ptr {{.*}}sret(%struct.st2)
+  struct st2 x;
+  x.a = a;
+  x.b = b;
+  return x;
+}
+
+__float128 h4(struct st2 x) {
+  // CHECK: define{{.*}}fp128 @h4(ptr {{.*}}byval(%struct.st2)
+  return x.a;
+}

``````````

</details>


https://github.com/llvm/llvm-project/pull/75156