[mips] Support 128-bit int in N32 ABI by overriding TargetInfo::hasInt128Type()

[dsanders]

Summary

The condition in the base class is rather strange. It says a target has the 128-bit integer type if the size of a pointer is >= 64-bits. N32 has 32-bit pointers but 64-bit integers. I'm a bit reluctant to change this for all targets so this patch makes the method virtual and overrides it for MIPS64.

[dsanders]

• Split int128 out to a separate test since O32 doesn't support it and fix two silly mistakes.

[dsanders]

Could you review this for me?

It touches common code so I'm also going to CC llvm-commits.

[dsanders]

Added llvm-commits.

[atanasyan]

LGTM

include/clang/Basic/TargetInfo.h

public:
   unsigned getLongAlign() const { return LongAlign; }
 
   /// getLongLongWidth/Align - Return the size of 'signed long long' and
   /// 'unsigned long long' for this target, in bits.
   unsigned getLongLongWidth() const { return LongLongWidth; }
   unsigned getLongLongAlign() const { return LongLongAlign; }
 
   /// \brief Determine whether the __int128 type is supported on this target.
-  bool hasInt128Type() const { return getPointerWidth(0) >= 64; } // FIXME
+  virtual bool hasInt128Type() const { return getPointerWidth(0) >= 64; } // FIXME
 
   /// \brief Return the alignment that is suitable for storing any
   /// object with a fundamental alignment requirement.
   unsigned getSuitableAlign() const { return SuitableAlign; }
 
   /// getMinGlobalAlign - Return the minimum alignment of a global variable,
   /// unless its alignment is explicitly reduced via attributes.
   unsigned getMinGlobalAlign() const { return MinGlobalAlign; }

lib/Basic/Targets.cpp

static const TargetInfo::GCCRegAlias GCCRegAliases[] = {
       { { "gp" }, "$28" },
       { { "sp","$sp" }, "$29" },
       { { "fp","$fp" }, "$30" },
       { { "ra" }, "$31" }
     };
     Aliases = GCCRegAliases;
     NumAliases = llvm::array_lengthof(GCCRegAliases);
   }
+
+  bool hasInt128Type() const override { return true; }
 };
 
 class Mips64EBTargetInfo : public Mips64TargetInfoBase {
   void setDescriptionString() override {
     if (ABI == "n32")
       DescriptionString = "E-m:m-p:32:32-i8:8:32-i16:16:32-i64:64-n32:64-S128";
     else
       DescriptionString = "E-m:m-i8:8:32-i16:16:32-i64:64-n32:64-S128";

test/CodeGen/mips-type-sizes-int128.c

+// RUN: not %clang_cc1 -triple mips-none-linux-gnu -emit-llvm -w -o - %s 2> %t1
+// RUN: FileCheck --check-prefix=O32 %s < %t1
+
+// RUN: %clang_cc1 -triple mips64-none-linux-gnu -emit-llvm -w -target-abi n32 -o - %s | FileCheck --check-prefix=NEW %s
+// RUN: %clang_cc1 -triple mips64-none-linux-gnu -emit-llvm -w -o - %s | FileCheck --check-prefix=NEW %s
+
+// O32 does not support __int128 so it must be tested separately
+// N32/N64 behave the same way so their tests have been combined into NEW
+
+int check_int128() {
+  return sizeof(__int128); // O32: :[[@LINE]]:17: error: __int128 is not supported on this target
+// NEW: ret i32 16
+}

test/CodeGen/mips-type-sizes.c

+// RUN: %clang_cc1 -triple mips-none-linux-gnu -emit-llvm -w -o - %s | FileCheck --check-prefix=ALL --check-prefix=O32 %s
+// RUN: %clang_cc1 -triple mips64-none-linux-gnu -emit-llvm -w -target-abi n32 -o - %s | FileCheck --check-prefix=ALL --check-prefix=N32 %s
+// RUN: %clang_cc1 -triple mips64-none-linux-gnu -emit-llvm -w -o - %s | FileCheck --check-prefix=ALL --check-prefix=N64 %s
+
+int check_char() {
+  return sizeof(char);
+// ALL: ret i32 1
+}
+
+int check_short() {
+  return sizeof(short);
+// ALL: ret i32 2
+}
+
+int check_int() {
+  return sizeof(int);
+// ALL: ret i32 4
+}
+
+int check_long() {
+  return sizeof(long);
+// O32: ret i32 4
+// N32: ret i32 4
+// N64: ret i32 8
+}
+
+int check_longlong() {
+  return sizeof(long long);
+// ALL: ret i32 8
+}
+
+int check_fp16() {
+  return sizeof(__fp16);
+// ALL: ret i32 2
+}
+
+int check_float() {
+  return sizeof(float);
+// ALL: ret i32 4
+}
+
+int check_double() {
+  return sizeof(double);
+// ALL: ret i32 8
+}
+
+int check_longdouble() {
+  return sizeof(long double);
+// O32: ret i32 8
+// N32: ret i32 16
+// N64: ret i32 16
+}
+
+int check_floatComplex() {
+  return sizeof(float _Complex);
+// ALL: ret i32 8
+}
+
+int check_doubleComplex() {
+  return sizeof(double _Complex);
+// ALL: ret i32 16
+}
+
+int check_longdoubleComplex() {
+  return sizeof(long double _Complex);
+// O32: ret i32 16
+// N32: ret i32 32
+// N64: ret i32 32
+}
+
+int check_bool() {
+  return sizeof(_Bool);
+// ALL: ret i32 1
+}
+
+int check_wchar() {
+  return sizeof(__WCHAR_TYPE__);
+// ALL: ret i32 4
+}
+
+int check_wchar_is_unsigned() {
+  return (__WCHAR_TYPE__)-1 > (__WCHAR_TYPE__)0;
+// ALL: ret i32 0
+}
+
+int check_ptr() {
+  return sizeof(void *);
+// O32: ret i32 4
+// N32: ret i32 4
+// N64: ret i32 8
+}
+