[llvm] 697f90e - [NFC] [PowerPC] Determine Endianness in PPCTargetMachine

[Nemanja Ivanovic via llvm-commits]

Author: Anshil Gandhi
Date: 2021-03-19T20:22:16-05:00
New Revision: 697f90ebfa7c48d61e7ed0d627b91f369b5014bd

URL: https://github.com/llvm/llvm-project/commit/697f90ebfa7c48d61e7ed0d627b91f369b5014bd
DIFF: https://github.com/llvm/llvm-project/commit/697f90ebfa7c48d61e7ed0d627b91f369b5014bd.diff

LOG: [NFC] [PowerPC] Determine Endianness in PPCTargetMachine

The TargetMachine uses the triple to determine endianness. Just
use that logic rather than replicating it in PPCSubtarget.

Differential revision: https://reviews.llvm.org/D98674

Added: 
    

Modified: 
    llvm/lib/Target/PowerPC/PPCSubtarget.cpp
    llvm/lib/Target/PowerPC/PPCTargetMachine.cpp
    llvm/lib/Target/PowerPC/PPCTargetMachine.h

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Target/PowerPC/PPCSubtarget.cpp b/llvm/lib/Target/PowerPC/PPCSubtarget.cpp
index bf98ea8a01d0..51c80e14398c 100644
--- a/llvm/lib/Target/PowerPC/PPCSubtarget.cpp
+++ b/llvm/lib/Target/PowerPC/PPCSubtarget.cpp
@@ -182,9 +182,7 @@ void PPCSubtarget::initSubtargetFeatures(StringRef CPU, StringRef FS) {
   StackAlignment = getPlatformStackAlignment();
 
   // Determine endianness.
-  // FIXME: Part of the TargetMachine.
-  IsLittleEndian = (TargetTriple.getArch() == Triple::ppc64le ||
-                    TargetTriple.getArch() == Triple::ppcle);
+  IsLittleEndian = TM.isLittleEndian();
 }
 
 bool PPCSubtarget::enableMachineScheduler() const { return true; }

diff  --git a/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp b/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp
index 47fe65640417..32b19d5ddd10 100644
--- a/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp
+++ b/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp
@@ -126,13 +126,17 @@ extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializePowerPCTarget() {
   initializeGlobalISel(PR);
 }
 
+static bool isLittleEndianTriple(const Triple &T) {
+  return T.getArch() == Triple::ppc64le || T.getArch() == Triple::ppcle;
+}
+
 /// Return the datalayout string of a subtarget.
 static std::string getDataLayoutString(const Triple &T) {
   bool is64Bit = T.getArch() == Triple::ppc64 || T.getArch() == Triple::ppc64le;
   std::string Ret;
 
   // Most PPC* platforms are big endian, PPC(64)LE is little endian.
-  if (T.getArch() == Triple::ppc64le || T.getArch() == Triple::ppcle)
+  if (isLittleEndianTriple(T))
     Ret = "e";
   else
     Ret = "E";
@@ -317,7 +321,8 @@ PPCTargetMachine::PPCTargetMachine(const Target &T, const Triple &TT,
                         getEffectiveRelocModel(TT, RM),
                         getEffectivePPCCodeModel(TT, CM, JIT), OL),
       TLOF(createTLOF(getTargetTriple())),
-      TargetABI(computeTargetABI(TT, Options)) {
+      TargetABI(computeTargetABI(TT, Options)),
+      Endianness(isLittleEndianTriple(TT) ? Endian::LITTLE : Endian::BIG) {
   initAsmInfo();
 }
 
@@ -540,6 +545,12 @@ PPCTargetMachine::getTargetTransformInfo(const Function &F) {
   return TargetTransformInfo(PPCTTIImpl(this, F));
 }
 
+bool PPCTargetMachine::isLittleEndian() const {
+  assert(Endianness != Endian::NOT_DETECTED &&
+         "Unable to determine endianness");
+  return Endianness == Endian::LITTLE;
+}
+
 static MachineSchedRegistry
 PPCPreRASchedRegistry("ppc-prera",
                       "Run PowerPC PreRA specific scheduler",

diff  --git a/llvm/lib/Target/PowerPC/PPCTargetMachine.h b/llvm/lib/Target/PowerPC/PPCTargetMachine.h
index 21faa4e710e3..ed9e74b72d1e 100644
--- a/llvm/lib/Target/PowerPC/PPCTargetMachine.h
+++ b/llvm/lib/Target/PowerPC/PPCTargetMachine.h
@@ -25,9 +25,12 @@ namespace llvm {
 class PPCTargetMachine final : public LLVMTargetMachine {
 public:
   enum PPCABI { PPC_ABI_UNKNOWN, PPC_ABI_ELFv1, PPC_ABI_ELFv2 };
+  enum Endian { NOT_DETECTED, LITTLE, BIG };
+
 private:
   std::unique_ptr<TargetLoweringObjectFile> TLOF;
   PPCABI TargetABI;
+  Endian Endianness = Endian::NOT_DETECTED;
 
   mutable StringMap<std::unique_ptr<PPCSubtarget>> SubtargetMap;
 
@@ -63,6 +66,8 @@ class PPCTargetMachine final : public LLVMTargetMachine {
     // Addrspacecasts are always noops.
     return true;
   }
+
+  bool isLittleEndian() const;
 };
 } // end namespace llvm