[AArch64] Add aarch64_vector_pcs function attribute to Clang

This is the Clang patch to complement the following LLVM patches: https://reviews.llvm.org/D51477 https://reviews.llvm.org/D51479 More information describing the vector ABI and procedure call standard can be found here: https://developer.arm.com/products/software-development-tools/\ hpc/arm-compiler-for-hpc/vector-function-abi Patch by Kerry McLaughlin. Reviewed By: rjmccall Differential Revision: https://reviews.llvm.org/D54425 llvm-svn: 347571
llvm · Nov 26, 2018 · 44a2253 · 44a2253
1 parent 10a7ee7
commit 44a2253
Show file tree

Hide file tree

Showing 16 changed files with 110 additions and 9 deletions.
diff --git a/clang/include/clang-c/Index.h b/clang/include/clang-c/Index.h
@@ -3336,6 +3336,7 @@ enum CXCallingConv {
   CXCallingConv_Swift = 13,
   CXCallingConv_PreserveMost = 14,
   CXCallingConv_PreserveAll = 15,
+  CXCallingConv_AArch64VectorCall = 16,
 
   CXCallingConv_Invalid = 100,
   CXCallingConv_Unexposed = 200

diff --git a/clang/include/clang/Basic/Attr.td b/clang/include/clang/Basic/Attr.td
@@ -1785,6 +1785,11 @@ def Pcs : DeclOrTypeAttr {
   let Documentation = [PcsDocs];
 }
 
+def AArch64VectorPcs: DeclOrTypeAttr {
+  let Spellings = [Clang<"aarch64_vector_pcs">];
+  let Documentation = [AArch64VectorPcsDocs];
+}
+
 def Pure : InheritableAttr {
   let Spellings = [GCC<"pure">];
   let Documentation = [Undocumented];

diff --git a/clang/include/clang/Basic/AttrDocs.td b/clang/include/clang/Basic/AttrDocs.td
@@ -1742,6 +1742,31 @@ similar to ``stdcall`` on x86. Valid parameter values are "aapcs" and
   }];
 }
 
+def AArch64VectorPcsDocs : Documentation {
+  let Category = DocCatCallingConvs;
+  let Content = [{
+On AArch64 targets, this attribute changes the calling convention of a
+function to preserve additional floating-point and Advanced SIMD registers
+relative to the default calling convention used for AArch64.
+
+This means it is more efficient to call such functions from code that performs
+extensive floating-point and vector calculations, because fewer live SIMD and FP
+registers need to be saved. This property makes it well-suited for e.g.
+floating-point or vector math library functions, which are typically leaf
+functions that require a small number of registers.
+
+However, using this attribute also means that it is more expensive to call
+a function that adheres to the default calling convention from within such
+a function. Therefore, it is recommended that this attribute is only used
+for leaf functions.
+
+For more information, see the documentation for `aarch64_vector_pcs`_ on
+the Arm Developer website.
+
+.. _`aarch64_vector_pcs`: https://developer.arm.com/products/software-development-tools/hpc/arm-compiler-for-hpc/vector-function-abi
+  }];
+}
+
 def RegparmDocs : Documentation {
   let Category = DocCatCallingConvs;
   let Content = [{

diff --git a/clang/include/clang/Basic/Specifiers.h b/clang/include/clang/Basic/Specifiers.h
@@ -251,6 +251,7 @@ namespace clang {
     CC_Swift,        // __attribute__((swiftcall))
     CC_PreserveMost, // __attribute__((preserve_most))
     CC_PreserveAll,  // __attribute__((preserve_all))
+    CC_AArch64VectorCall, // __attribute__((aarch64_vector_pcs))
   };
 
   /// Checks whether the given calling convention supports variadic

diff --git a/clang/lib/AST/ItaniumMangle.cpp b/clang/lib/AST/ItaniumMangle.cpp
@@ -2659,6 +2659,7 @@ StringRef CXXNameMangler::getCallingConvQualifierName(CallingConv CC) {
   case CC_X86RegCall:
   case CC_AAPCS:
   case CC_AAPCS_VFP:
+  case CC_AArch64VectorCall:
   case CC_IntelOclBicc:
   case CC_SpirFunction:
   case CC_OpenCLKernel:

diff --git a/clang/lib/AST/Type.cpp b/clang/lib/AST/Type.cpp
@@ -2824,6 +2824,7 @@ StringRef FunctionType::getNameForCallConv(CallingConv CC) {
   case CC_X86RegCall : return "regcall";
   case CC_AAPCS: return "aapcs";
   case CC_AAPCS_VFP: return "aapcs-vfp";
+  case CC_AArch64VectorCall: return "aarch64_vector_pcs";
   case CC_IntelOclBicc: return "intel_ocl_bicc";
   case CC_SpirFunction: return "spir_function";
   case CC_OpenCLKernel: return "opencl_kernel";
@@ -3216,6 +3217,7 @@ bool AttributedType::isCallingConv() const {
   case attr::RegCall:
   case attr::SwiftCall:
   case attr::VectorCall:
+  case attr::AArch64VectorPcs:
   case attr::Pascal:
   case attr::MSABI:
   case attr::SysVABI:

diff --git a/clang/lib/AST/TypePrinter.cpp b/clang/lib/AST/TypePrinter.cpp
@@ -861,6 +861,9 @@ void TypePrinter::printFunctionAfter(const FunctionType::ExtInfo &Info,
     case CC_AAPCS_VFP:
       OS << " __attribute__((pcs(\"aapcs-vfp\")))";
       break;
+    case CC_AArch64VectorCall:
+      OS << "__attribute__((aarch64_vector_pcs))";
+      break;
     case CC_IntelOclBicc:
       OS << " __attribute__((intel_ocl_bicc))";
       break;
@@ -1492,7 +1495,7 @@ void TypePrinter::printAttributedAfter(const AttributedType *T,
    OS << ')';
    break;
   }
-
+  case attr::AArch64VectorPcs: OS << "aarch64_vector_pcs"; break;
   case attr::IntelOclBicc: OS << "inteloclbicc"; break;
   case attr::PreserveMost:
     OS << "preserve_most";

diff --git a/clang/lib/Basic/Targets/AArch64.cpp b/clang/lib/Basic/Targets/AArch64.cpp
@@ -273,6 +273,7 @@ AArch64TargetInfo::checkCallingConvention(CallingConv CC) const {
   case CC_PreserveMost:
   case CC_PreserveAll:
   case CC_OpenCLKernel:
+  case CC_AArch64VectorCall:
   case CC_Win64:
     return CCCR_OK;
   default:

diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
@@ -59,6 +59,7 @@ unsigned CodeGenTypes::ClangCallConvToLLVMCallConv(CallingConv CC) {
   case CC_X86Pascal: return llvm::CallingConv::C;
   // TODO: Add support for __vectorcall to LLVM.
   case CC_X86VectorCall: return llvm::CallingConv::X86_VectorCall;
+  case CC_AArch64VectorCall: return llvm::CallingConv::AArch64_VectorCall;
   case CC_SpirFunction: return llvm::CallingConv::SPIR_FUNC;
   case CC_OpenCLKernel: return CGM.getTargetCodeGenInfo().getOpenCLKernelCallingConv();
   case CC_PreserveMost: return llvm::CallingConv::PreserveMost;
@@ -214,6 +215,9 @@ static CallingConv getCallingConventionForDecl(const Decl *D, bool IsWindows) {
   if (PcsAttr *PCS = D->getAttr<PcsAttr>())
     return (PCS->getPCS() == PcsAttr::AAPCS ? CC_AAPCS : CC_AAPCS_VFP);
 
+  if (D->hasAttr<AArch64VectorPcsAttr>())
+    return CC_AArch64VectorCall;
+
   if (D->hasAttr<IntelOclBiccAttr>())
     return CC_IntelOclBicc;
 

diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -1102,6 +1102,7 @@ static unsigned getDwarfCC(CallingConv CC) {
   case CC_X86_64SysV:
     return llvm::dwarf::DW_CC_LLVM_X86_64SysV;
   case CC_AAPCS:
+  case CC_AArch64VectorCall:
     return llvm::dwarf::DW_CC_LLVM_AAPCS;
   case CC_AAPCS_VFP:
     return llvm::dwarf::DW_CC_LLVM_AAPCS_VFP;

diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -4291,6 +4291,11 @@ static void handleCallConvAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
                        AL.getAttributeSpellingListIndex()));
     return;
   }
+  case ParsedAttr::AT_AArch64VectorPcs:
+    D->addAttr(::new(S.Context)
+               AArch64VectorPcsAttr(AL.getRange(), S.Context,
+                                    AL.getAttributeSpellingListIndex()));
+    return;
   case ParsedAttr::AT_IntelOclBicc:
     D->addAttr(::new (S.Context)
                IntelOclBiccAttr(AL.getRange(), S.Context,
@@ -4368,6 +4373,9 @@ bool Sema::CheckCallingConvAttr(const ParsedAttr &Attrs, CallingConv &CC,
   case ParsedAttr::AT_VectorCall:
     CC = CC_X86VectorCall;
     break;
+  case ParsedAttr::AT_AArch64VectorPcs:
+    CC = CC_AArch64VectorCall;
+    break;
   case ParsedAttr::AT_RegCall:
     CC = CC_X86RegCall;
     break;
@@ -5840,14 +5848,14 @@ static void handleDeprecatedAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
   if (AL.isDeclspecAttribute() || AL.isCXX11Attribute())
     checkAttributeAtMostNumArgs(S, AL, 1);
   else if (AL.isArgExpr(1) && AL.getArgAsExpr(1) &&
-           !S.checkStringLiteralArgumentAttr(AL, 1, Replacement))
-    return;
-
-  if (!S.getLangOpts().CPlusPlus14 && AL.isCXX11Attribute() && !AL.isGNUScope())
-    S.Diag(AL.getLoc(), diag::ext_cxx14_attr) << AL;
-
-  D->addAttr(::new (S.Context)
-                 DeprecatedAttr(AL.getRange(), S.Context, Str, Replacement,
+           !S.checkStringLiteralArgumentAttr(AL, 1, Replacement))
+    return;
+
+  if (!S.getLangOpts().CPlusPlus14 && AL.isCXX11Attribute() && !AL.isGNUScope())
+    S.Diag(AL.getLoc(), diag::ext_cxx14_attr) << AL;
+
+  D->addAttr(::new (S.Context)
+                 DeprecatedAttr(AL.getRange(), S.Context, Str, Replacement,
                                 AL.getAttributeSpellingListIndex()));
 }
 
@@ -6493,6 +6501,7 @@ static void ProcessDeclAttribute(Sema &S, Scope *scope, Decl *D,
   case ParsedAttr::AT_IntelOclBicc:
   case ParsedAttr::AT_PreserveMost:
   case ParsedAttr::AT_PreserveAll:
+  case ParsedAttr::AT_AArch64VectorPcs:
     handleCallConvAttr(S, D, AL);
     break;
   case ParsedAttr::AT_Suppress:

diff --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp
@@ -116,6 +116,7 @@ static void diagnoseBadTypeAttribute(Sema &S, const ParsedAttr &attr,
   case ParsedAttr::AT_Pascal:                                                  \
   case ParsedAttr::AT_SwiftCall:                                               \
   case ParsedAttr::AT_VectorCall:                                              \
+  case ParsedAttr::AT_AArch64VectorPcs:                                        \
   case ParsedAttr::AT_MSABI:                                                   \
   case ParsedAttr::AT_SysVABI:                                                 \
   case ParsedAttr::AT_Pcs:                                                     \
@@ -6653,6 +6654,8 @@ static Attr *getCCTypeAttr(ASTContext &Ctx, ParsedAttr &Attr) {
     return createSimpleAttr<SwiftCallAttr>(Ctx, Attr);
   case ParsedAttr::AT_VectorCall:
     return createSimpleAttr<VectorCallAttr>(Ctx, Attr);
+  case ParsedAttr::AT_AArch64VectorPcs:
+    return createSimpleAttr<AArch64VectorPcsAttr>(Ctx, Attr);
   case ParsedAttr::AT_Pcs: {
     // The attribute may have had a fixit applied where we treated an
     // identifier as a string literal.  The contents of the string are valid,

diff --git a/clang/test/CodeGen/aarch64-vpcs.c b/clang/test/CodeGen/aarch64-vpcs.c
@@ -0,0 +1,23 @@
+// RUN: %clang_cc1 -triple aarch64-linux-gnu -emit-llvm -o - %s | FileCheck %s -check-prefix=CHECKC
+// RUN: %clang_cc1 -triple aarch64-linux-gnu -emit-llvm -x c++ -o - %s | FileCheck %s -check-prefix=CHECKCXX
+// RUN: %clang_cc1 -triple i686-pc-linux-gnu -verify %s
+
+void __attribute__((aarch64_vector_pcs)) f(int *); // expected-warning {{calling convention 'aarch64_vector_pcs' ignored for this target}}
+
+// CHECKC: define void @g(
+// CHECKCXX: define void @_Z1gPi(
+void g(int *a) {
+
+// CHECKC: call aarch64_vector_pcs void @f(
+// CHECKCXX: call aarch64_vector_pcs void @_Z1fPi
+  f(a);
+}
+
+// CHECKC: declare aarch64_vector_pcs void @f(
+// CHECKCXX: declare aarch64_vector_pcs void @_Z1fPi
+
+void __attribute__((aarch64_vector_pcs)) h(int *a){ // expected-warning {{calling convention 'aarch64_vector_pcs' ignored for this target}}
+// CHECKC: define aarch64_vector_pcs void @h(
+// CHECKCXX: define aarch64_vector_pcs void @_Z1hPi(
+  f(a);
+}
diff --git a/clang/test/Sema/aarch64-vpcs.c b/clang/test/Sema/aarch64-vpcs.c
@@ -0,0 +1,19 @@
+// RUN: %clang_cc1 -triple aarch64-linux-gnu -verify %s
+
+typedef __attribute__((aarch64_vector_pcs)) int invalid_typedef; // expected-warning {{'aarch64_vector_pcs' only applies to function types; type here is 'int'}}
+
+void __attribute__((aarch64_vector_pcs(0))) foo0(void); // expected-error {{'aarch64_vector_pcs' attribute takes no arguments}}
+
+void __attribute__((aarch64_vector_pcs, preserve_all)) foo1(void); // expected-error {{not compatible}}
+
+void __attribute__((cdecl)) foo2(void);                // expected-note {{previous declaration is here}}
+void __attribute__((aarch64_vector_pcs)) foo2(void) {} // expected-error {{function declared 'aarch64_vector_pcs' here was previously declared 'cdecl'}}
+
+void foo3(void);                                       // expected-note {{previous declaration is here}}
+void __attribute__((aarch64_vector_pcs)) foo3(void) {} // expected-error {{function declared 'aarch64_vector_pcs' here was previously declared without calling convention}}
+
+typedef int (*fn_ty)(void);
+typedef int __attribute__((aarch64_vector_pcs)) (*aavpcs_fn_ty)(void);
+void foo4(fn_ty ptr1, aavpcs_fn_ty ptr2) {
+  ptr1 = ptr2; // expected-warning {{incompatible function pointer types}}
+}
diff --git a/clang/test/Sema/callingconv.c b/clang/test/Sema/callingconv.c
@@ -51,6 +51,8 @@ int __attribute__((pcs("aapcs"))) pcs5(void); // expected-warning {{calling conv
 int __attribute__((pcs("aapcs-vfp"))) pcs6(void); // expected-warning {{calling convention 'pcs' ignored for this target}}
 int __attribute__((pcs("foo"))) pcs7(void); // expected-error {{invalid PCS type}}
 
+int __attribute__((aarch64_vector_pcs)) aavpcs(void); // expected-warning {{calling convention 'aarch64_vector_pcs' ignored for this target}}
+
 // PR6361
 void ctest3();
 void __attribute__((cdecl)) ctest3() {}

diff --git a/clang/tools/libclang/CXType.cpp b/clang/tools/libclang/CXType.cpp
@@ -651,6 +651,7 @@ CXCallingConv clang_getFunctionTypeCallingConv(CXType X) {
       TCALLINGCONV(X86Pascal);
       TCALLINGCONV(X86RegCall);
       TCALLINGCONV(X86VectorCall);
+      TCALLINGCONV(AArch64VectorCall);
       TCALLINGCONV(Win64);
       TCALLINGCONV(X86_64SysV);
       TCALLINGCONV(AAPCS);