Factor ARM triple parsing out of ARMSubtarget. Another step towards making ARM subtarget info available to MC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134569 91177308-0d34-0410-b5e6-96231b3b80d8

7 files changed, 84 insertions, 91 deletions

diff --git a/lib/Target/ARM/ARM.td b/lib/Target/ARM/ARM.td
index 39a3528836..6d3a42fa40 100644
--- a/lib/Target/ARM/ARM.td
+++ b/lib/Target/ARM/ARM.td
@@ -27,7 +27,7 @@ def FeatureVFP3 : SubtargetFeature<"vfp3", "ARMFPUType", "VFPv3",
                                    "Enable VFP3 instructions">;
 def FeatureNEON : SubtargetFeature<"neon", "ARMFPUType", "NEON",
                                    "Enable NEON instructions">;
-def FeatureThumb2 : SubtargetFeature<"thumb2", "ThumbMode", "Thumb2",
+def FeatureThumb2 : SubtargetFeature<"thumb2", "HasThumb2", "true",
                                      "Enable Thumb2 instructions">;
 def FeatureNoARM  : SubtargetFeature<"noarm", "NoARM", "true",
                                      "Does not support ARM mode execution">;
diff --git a/lib/Target/ARM/ARMSubtarget.cpp b/lib/Target/ARM/ARMSubtarget.cpp
index a7010c5be1..da572d2e5e 100644
--- a/lib/Target/ARM/ARMSubtarget.cpp
+++ b/lib/Target/ARM/ARMSubtarget.cpp
@@ -37,7 +37,7 @@ StrictAlign("arm-strict-align", cl::Hidden,
             cl::desc("Disallow all unaligned memory accesses"));
 
 ARMSubtarget::ARMSubtarget(const std::string &TT, const std::string &CPU,
-                           const std::string &FS, bool isT)
+                           const std::string &FS)
   : ARMGenSubtargetInfo()
   , ARMArchVersion(V4)
   , ARMProcFamily(Others)
@@ -46,8 +46,8 @@ ARMSubtarget::ARMSubtarget(const std::string &TT, const std::string &CPU,
   , SlowFPVMLx(false)
   , HasVMLxForwarding(false)
   , SlowFPBrcc(false)
-  , IsThumb(isT)
-  , ThumbMode(Thumb1)
+  , IsThumb(false)
+  , HasThumb2(false)
   , NoARM(false)
   , PostRAScheduler(false)
   , IsR9Reserved(ReserveR9)
@@ -68,65 +68,8 @@ ARMSubtarget::ARMSubtarget(const std::string &TT, const std::string &CPU,
   , TargetTriple(TT)
   , TargetABI(ARM_ABI_APCS) {
   // Determine default and user specified characteristics
-
-  // When no arch is specified either by CPU or by attributes, make the default
-  // ARMv4T.
-  const char *ARMArchFeature = "";
   if (CPUString.empty())
     CPUString = "generic";
-  if (CPUString == "generic" && (FS.empty() || FS == "generic")) {
-    ARMArchVersion = V4T;
-    ARMArchFeature = "+v4t";
-  }
-
-  // Set the boolean corresponding to the current target triple, or the default
-  // if one cannot be determined, to true.
-  unsigned Len = TT.length();
-  unsigned Idx = 0;
-
-  if (Len >= 5 && TT.substr(0, 4) == "armv")
-    Idx = 4;
-  else if (Len >= 6 && TT.substr(0, 5) == "thumb") {
-    IsThumb = true;
-    if (Len >= 7 && TT[5] == 'v')
-      Idx = 6;
-  }
-  if (Idx) {
-    unsigned SubVer = TT[Idx];
-    if (SubVer >= '7' && SubVer <= '9') {
-      ARMArchVersion = V7A;
-      ARMArchFeature = "+v7a";
-      if (Len >= Idx+2 && TT[Idx+1] == 'm') {
-        ARMArchVersion = V7M;
-        ARMArchFeature = "+v7m";
-      } else if (Len >= Idx+3 && TT[Idx+1] == 'e'&& TT[Idx+2] == 'm') {
-        ARMArchVersion = V7EM;
-        ARMArchFeature = "+v7em";
-      }
-    } else if (SubVer == '6') {
-      ARMArchVersion = V6;
-      ARMArchFeature = "+v6";
-      if (Len >= Idx+3 && TT[Idx+1] == 't' && TT[Idx+2] == '2') {
-        ARMArchVersion = V6T2;
-        ARMArchFeature = "+v6t2";
-      }
-    } else if (SubVer == '5') {
-      ARMArchVersion = V5T;
-      ARMArchFeature = "+v5t";
-      if (Len >= Idx+3 && TT[Idx+1] == 't' && TT[Idx+2] == 'e') {
-        ARMArchVersion = V5TE;
-        ARMArchFeature = "+v5te";
-      }
-    } else if (SubVer == '4') {
-      if (Len >= Idx+2 && TT[Idx+1] == 't') {
-        ARMArchVersion = V4T;
-        ARMArchFeature = "+v4t";
-      } else {
-        ARMArchVersion = V4;
-        ARMArchFeature = "";
-      }
-    }
-  }
 
   if (TT.find("eabi") != std::string::npos)
     TargetABI = ARM_ABI_AAPCS;
@@ -134,12 +77,20 @@ ARMSubtarget::ARMSubtarget(const std::string &TT, const std::string &CPU,
   // Insert the architecture feature derived from the target triple into the
   // feature string. This is important for setting features that are implied
   // based on the architecture version.
-  std::string FSWithArch = std::string(ARMArchFeature);
-  if (FSWithArch.empty())
-    FSWithArch = FS;
-  else if (!FS.empty())
-    FSWithArch = FSWithArch + "," + FS;
-  ParseSubtargetFeatures(FSWithArch, CPUString);
+  std::string ArchFS = ARM_MC::ParseARMTriple(TT, IsThumb);
+  if (!FS.empty()) {
+    if (!ArchFS.empty())
+      ArchFS = ArchFS + "," + FS;
+    else
+      ArchFS = FS;
+  }
+
+  ParseSubtargetFeatures(ArchFS, CPUString);
+
+  // Thumb2 implies at least V6T2. FIXME: Fix tests to explicitly specify a
+  // ARM version or CPU and then remove this.
+  if (ARMArchVersion < V6T2 && hasThumb2())
+    ARMArchVersion = V6T2;
 
   // Initialize scheduling itinerary for the specified CPU.
   InstrItins = getInstrItineraryForCPU(CPUString);
@@ -147,12 +98,6 @@ ARMSubtarget::ARMSubtarget(const std::string &TT, const std::string &CPU,
   // After parsing Itineraries, set ItinData.IssueWidth.
   computeIssueWidth();
 
-  // Thumb2 implies at least V6T2.
-  if (ARMArchVersion >= V6T2)
-    ThumbMode = Thumb2;
-  else if (ThumbMode >= Thumb2)
-    ARMArchVersion = V6T2;
-
   if (isAAPCS_ABI())
     stackAlignment = 8;
 
diff --git a/lib/Target/ARM/ARMSubtarget.h b/lib/Target/ARM/ARMSubtarget.h
index 66e4426091..6969c38016 100644
--- a/lib/Target/ARM/ARMSubtarget.h
+++ b/lib/Target/ARM/ARMSubtarget.h
@@ -14,6 +14,7 @@
 #ifndef ARMSUBTARGET_H
 #define ARMSUBTARGET_H
 
+#include "MCTargetDesc/ARMMCTargetDesc.h"
 #include "llvm/Target/TargetSubtargetInfo.h"
 #include "llvm/MC/MCInstrItineraries.h"
 #include "llvm/ADT/Triple.h"
@@ -39,11 +40,6 @@ protected:
     None, VFPv2, VFPv3, NEON
   };
 
-  enum ThumbTypeEnum {
-    Thumb1,
-    Thumb2
-  };
-
   /// ARMArchVersion - ARM architecture version: V4, V4T (base), V5T, V5TE,
   /// V6, V6T2, V7A, V7M, V7EM.
   ARMArchEnum ARMArchVersion;
@@ -73,8 +69,8 @@ protected:
   /// IsThumb - True if we are in thumb mode, false if in ARM mode.
   bool IsThumb;
 
-  /// ThumbMode - Indicates supported Thumb version.
-  ThumbTypeEnum ThumbMode;
+  /// HasThumb2 - True if Thumb2 instructions are supported.
+  bool HasThumb2;
 
   /// NoARM - True if subtarget does not support ARM mode execution.
   bool NoARM;
@@ -161,7 +157,7 @@ protected:
   /// of the specified triple.
   ///
   ARMSubtarget(const std::string &TT, const std::string &CPU,
-               const std::string &FS, bool isThumb);
+               const std::string &FS);
 
   /// getMaxInlineSizeThreshold - Returns the maximum memset / memcpy size
   /// that still makes it profitable to inline the call.
@@ -217,9 +213,9 @@ protected:
   bool isAAPCS_ABI() const { return TargetABI == ARM_ABI_AAPCS; }
 
   bool isThumb() const { return IsThumb; }
-  bool isThumb1Only() const { return IsThumb && (ThumbMode == Thumb1); }
-  bool isThumb2() const { return IsThumb && (ThumbMode == Thumb2); }
-  bool hasThumb2() const { return ThumbMode >= Thumb2; }
+  bool isThumb1Only() const { return IsThumb && !HasThumb2; }
+  bool isThumb2() const { return IsThumb && HasThumb2; }
+  bool hasThumb2() const { return HasThumb2; }
 
   bool isR9Reserved() const { return IsR9Reserved; }
 
diff --git a/lib/Target/ARM/ARMTargetMachine.cpp b/lib/Target/ARM/ARMTargetMachine.cpp
index 80e7d55947..bb3184ee73 100644
--- a/lib/Target/ARM/ARMTargetMachine.cpp
+++ b/lib/Target/ARM/ARMTargetMachine.cpp
@@ -79,10 +79,9 @@ extern "C" void LLVMInitializeARMTarget() {
 ARMBaseTargetMachine::ARMBaseTargetMachine(const Target &T,
                                            const std::string &TT,
                                            const std::string &CPU,
-                                           const std::string &FS,
-                                           bool isThumb)
+                                           const std::string &FS)
   : LLVMTargetMachine(T, TT),
-    Subtarget(TT, CPU, FS, isThumb),
+    Subtarget(TT, CPU, FS),
     JITInfo(),
     InstrItins(Subtarget.getInstrItineraryData()) {
   DefRelocModel = getRelocationModel();
@@ -95,7 +94,7 @@ ARMBaseTargetMachine::ARMBaseTargetMachine(const Target &T,
 ARMTargetMachine::ARMTargetMachine(const Target &T, const std::string &TT,
                                    const std::string &CPU,
                                    const std::string &FS)
-  : ARMBaseTargetMachine(T, TT, CPU, FS, false), InstrInfo(Subtarget),
+  : ARMBaseTargetMachine(T, TT, CPU, FS), InstrInfo(Subtarget),
     DataLayout(Subtarget.isAPCS_ABI() ?
                std::string("e-p:32:32-f64:32:64-i64:32:64-"
                            "v128:32:128-v64:32:64-n32") :
@@ -113,7 +112,7 @@ ARMTargetMachine::ARMTargetMachine(const Target &T, const std::string &TT,
 ThumbTargetMachine::ThumbTargetMachine(const Target &T, const std::string &TT,
                                        const std::string &CPU,
                                        const std::string &FS)
-  : ARMBaseTargetMachine(T, TT, CPU, FS, true),
+  : ARMBaseTargetMachine(T, TT, CPU, FS),
     InstrInfo(Subtarget.hasThumb2()
               ? ((ARMBaseInstrInfo*)new Thumb2InstrInfo(Subtarget))
               : ((ARMBaseInstrInfo*)new Thumb1InstrInfo(Subtarget))),
diff --git a/lib/Target/ARM/ARMTargetMachine.h b/lib/Target/ARM/ARMTargetMachine.h
index a4a792763d..bc3d46a50e 100644
--- a/lib/Target/ARM/ARMTargetMachine.h
+++ b/lib/Target/ARM/ARMTargetMachine.h
@@ -41,8 +41,7 @@ private:
 
 public:
   ARMBaseTargetMachine(const Target &T, const std::string &TT,
-                       const std::string &CPU, const std::string &FS,
-                       bool isThumb);
+                       const std::string &CPU, const std::string &FS);
 
   virtual       ARMJITInfo       *getJITInfo()         { return &JITInfo; }
   virtual const ARMSubtarget  *getSubtargetImpl() const { return &Subtarget; }
diff --git a/lib/Target/ARM/MCTargetDesc/ARMMCTargetDesc.cpp b/lib/Target/ARM/MCTargetDesc/ARMMCTargetDesc.cpp
index 198c25d863..f2b6d25224 100644
--- a/lib/Target/ARM/MCTargetDesc/ARMMCTargetDesc.cpp
+++ b/lib/Target/ARM/MCTargetDesc/ARMMCTargetDesc.cpp
@@ -72,3 +72,49 @@ extern "C" void LLVMInitializeARMMCSubtargetInfo() {
   TargetRegistry::RegisterMCSubtargetInfo(TheThumbTarget,
                                           createARMMCSubtargetInfo);
 }
+
+std::string ARM_MC::ParseARMTriple(StringRef TT, bool &IsThumb) {
+  // Set the boolean corresponding to the current target triple, or the default
+  // if one cannot be determined, to true.
+  unsigned Len = TT.size();
+  unsigned Idx = 0;
+
+  if (Len >= 5 && TT.substr(0, 4) == "armv")
+    Idx = 4;
+  else if (Len >= 6 && TT.substr(0, 5) == "thumb") {
+    IsThumb = true;
+    if (Len >= 7 && TT[5] == 'v')
+      Idx = 6;
+  }
+
+  std::string ARMArchFeature;
+  if (Idx) {
+    unsigned SubVer = TT[Idx];
+    if (SubVer >= '7' && SubVer <= '9') {
+      ARMArchFeature = "+v7a";
+      if (Len >= Idx+2 && TT[Idx+1] == 'm') {
+        ARMArchFeature = "+v7m";
+      } else if (Len >= Idx+3 && TT[Idx+1] == 'e'&& TT[Idx+2] == 'm') {
+        ARMArchFeature = "+v7em";
+      }
+    } else if (SubVer == '6') {
+      ARMArchFeature = "+v6";
+      if (Len >= Idx+3 && TT[Idx+1] == 't' && TT[Idx+2] == '2') {
+        ARMArchFeature = "+v6t2";
+      }
+    } else if (SubVer == '5') {
+      ARMArchFeature = "+v5t";
+      if (Len >= Idx+3 && TT[Idx+1] == 't' && TT[Idx+2] == 'e') {
+        ARMArchFeature = "+v5te";
+      }
+    } else if (SubVer == '4') {
+      if (Len >= Idx+2 && TT[Idx+1] == 't') {
+        ARMArchFeature = "+v4t";
+      } else {
+        ARMArchFeature = "";
+      }
+    }
+  }
+
+  return ARMArchFeature;
+}
diff --git a/lib/Target/ARM/MCTargetDesc/ARMMCTargetDesc.h b/lib/Target/ARM/MCTargetDesc/ARMMCTargetDesc.h
index a486cffcfd..0c2378409f 100644
--- a/lib/Target/ARM/MCTargetDesc/ARMMCTargetDesc.h
+++ b/lib/Target/ARM/MCTargetDesc/ARMMCTargetDesc.h
@@ -14,10 +14,18 @@
 #ifndef ARMMCTARGETDESC_H
 #define ARMMCTARGETDESC_H
 
+#include <string>
+
 namespace llvm {
 class Target;
+class StringRef;
 
 extern Target TheARMTarget, TheThumbTarget;
+
+namespace ARM_MC {
+  std::string ParseARMTriple(StringRef TT, bool &IsThumb);
+}
+
 } // End llvm namespace
 
 // Defines symbolic names for ARM registers.  This defines a mapping from