r363973 - Fix passing structs and AVX vectors through sysv_abi

[Reid Kleckner via cfe-commits]

Author: rnk
Date: Thu Jun 20 13:07:20 2019
New Revision: 363973

URL: http://llvm.org/viewvc/llvm-project?rev=363973&view=rev
Log:
Fix passing structs and AVX vectors through sysv_abi

Do this the same way we did it for ms_abi in r324594.

Fixes PR36806.

Added:
    cfe/trunk/test/CodeGen/sysv_abi.c
Modified:
    cfe/trunk/lib/CodeGen/TargetInfo.cpp

Modified: cfe/trunk/lib/CodeGen/TargetInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/TargetInfo.cpp?rev=363973&r1=363972&r2=363973&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/TargetInfo.cpp (original)
+++ cfe/trunk/lib/CodeGen/TargetInfo.cpp Thu Jun 20 13:07:20 2019
@@ -2222,8 +2222,8 @@ public:
 /// WinX86_64ABIInfo - The Windows X86_64 ABI information.
 class WinX86_64ABIInfo : public SwiftABIInfo {
 public:
-  WinX86_64ABIInfo(CodeGen::CodeGenTypes &CGT)
-      : SwiftABIInfo(CGT),
+  WinX86_64ABIInfo(CodeGen::CodeGenTypes &CGT, X86AVXABILevel AVXLevel)
+      : SwiftABIInfo(CGT), AVXLevel(AVXLevel),
         IsMingw64(getTarget().getTriple().isWindowsGNUEnvironment()) {}
 
   void computeInfo(CGFunctionInfo &FI) const override;
@@ -2259,7 +2259,9 @@ private:
   void computeVectorCallArgs(CGFunctionInfo &FI, unsigned FreeSSERegs,
                              bool IsVectorCall, bool IsRegCall) const;
 
-    bool IsMingw64;
+  X86AVXABILevel AVXLevel;
+
+  bool IsMingw64;
 };
 
 class X86_64TargetCodeGenInfo : public TargetCodeGenInfo {
@@ -2409,7 +2411,7 @@ class WinX86_64TargetCodeGenInfo : publi
 public:
   WinX86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT,
                              X86AVXABILevel AVXLevel)
-      : TargetCodeGenInfo(new WinX86_64ABIInfo(CGT)) {}
+      : TargetCodeGenInfo(new WinX86_64ABIInfo(CGT, AVXLevel)) {}
 
   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
                            CodeGen::CodeGenModule &CGM) const override;
@@ -3562,7 +3564,7 @@ void X86_64ABIInfo::computeInfo(CGFuncti
   // using __attribute__((ms_abi)). In such case to correctly emit Win64
   // compatible code delegate this call to WinX86_64ABIInfo::computeInfo.
   if (CallingConv == llvm::CallingConv::Win64) {
-    WinX86_64ABIInfo Win64ABIInfo(CGT);
+    WinX86_64ABIInfo Win64ABIInfo(CGT, AVXLevel);
     Win64ABIInfo.computeInfo(FI);
     return;
   }
@@ -4016,9 +4018,17 @@ void WinX86_64ABIInfo::computeVectorCall
 }
 
 void WinX86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
-  bool IsVectorCall =
-      FI.getCallingConvention() == llvm::CallingConv::X86_VectorCall;
-  bool IsRegCall = FI.getCallingConvention() == llvm::CallingConv::X86_RegCall;
+  const unsigned CC = FI.getCallingConvention();
+  bool IsVectorCall = CC == llvm::CallingConv::X86_VectorCall;
+  bool IsRegCall = CC == llvm::CallingConv::X86_RegCall;
+
+  // If __attribute__((sysv_abi)) is in use, use the SysV argument
+  // classification rules.
+  if (CC == llvm::CallingConv::X86_64_SysV) {
+    X86_64ABIInfo SysVABIInfo(CGT, AVXLevel);
+    SysVABIInfo.computeInfo(FI);
+    return;
+  }
 
   unsigned FreeSSERegs = 0;
   if (IsVectorCall) {

Added: cfe/trunk/test/CodeGen/sysv_abi.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/sysv_abi.c?rev=363973&view=auto
==============================================================================
--- cfe/trunk/test/CodeGen/sysv_abi.c (added)
+++ cfe/trunk/test/CodeGen/sysv_abi.c Thu Jun 20 13:07:20 2019
@@ -0,0 +1,49 @@
+// RUN: %clang_cc1 -triple x86_64-pc-win32 -emit-llvm  -target-cpu skylake-avx512 < %s | FileCheck %s --check-prefixes=CHECK,AVX
+// RUN: %clang_cc1 -triple x86_64-linux -emit-llvm  -target-cpu skylake-avx512 < %s | FileCheck %s --check-prefixes=CHECK,AVX
+// RUN: %clang_cc1 -triple x86_64-pc-win32 -emit-llvm < %s | FileCheck %s --check-prefixes=CHECK,NOAVX
+// RUN: %clang_cc1 -triple x86_64-linux -emit-llvm < %s | FileCheck %s --check-prefixes=CHECK,NOAVX
+
+#define SYSV_CC __attribute__((sysv_abi))
+
+// Make sure we coerce structs according to the SysV rules instead of passing
+// them indirectly as we would for Win64.
+struct StringRef {
+  char *Str;
+  __SIZE_TYPE__ Size;
+};
+extern volatile char gc;
+void SYSV_CC take_stringref(struct StringRef s);
+void callit() {
+  struct StringRef s = {"asdf", 4};
+  take_stringref(s);
+}
+// CHECK: define {{(dso_local )?}}void @callit()
+// CHECK: call {{(x86_64_sysvcc )?}}void @take_stringref(i8* {{[^,]*}}, i64 {{[^,]*}})
+// CHECK: declare {{(dso_local )?}}{{(x86_64_sysvcc )?}}void @take_stringref(i8*, i64)
+
+// Check that we pass vectors directly if the target feature is enabled, and
+// not otherwise.
+typedef __attribute__((vector_size(32))) float my_m256;
+typedef __attribute__((vector_size(64))) float my_m512;
+
+my_m256 SYSV_CC get_m256(void);
+void SYSV_CC take_m256(my_m256);
+my_m512 SYSV_CC get_m512(void);
+void SYSV_CC take_m512(my_m512);
+
+void use_vectors() {
+  my_m256 v1 = get_m256();
+  take_m256(v1);
+  my_m512 v2 = get_m512();
+  take_m512(v2);
+}
+
+// CHECK: define {{(dso_local )?}}void @use_vectors()
+// AVX: call {{(x86_64_sysvcc )?}}<8 x float> @get_m256()
+// AVX: call {{(x86_64_sysvcc )?}}void @take_m256(<8 x float> %{{.*}})
+// AVX: call {{(x86_64_sysvcc )?}}<16 x float> @get_m512()
+// AVX: call {{(x86_64_sysvcc )?}}void @take_m512(<16 x float> %{{.*}})
+// NOAVX: call {{(x86_64_sysvcc )?}}<8 x float> @get_m256()
+// NOAVX: call {{(x86_64_sysvcc )?}}void @take_m256(<8 x float>* byval(<8 x float>) align 32 %{{.*}})
+// NOAVX: call {{(x86_64_sysvcc )?}}<16 x float> @get_m512()
+// NOAVX: call {{(x86_64_sysvcc )?}}void @take_m512(<16 x float>* byval(<16 x float>) align 64 %{{.*}})