r174140 - Enable -fno-altivec, -mno-altivec for PowerPC.

[Bill Schmidt]

Author: wschmidt
Date: Thu Jan 31 20:14:03 2013
New Revision: 174140

URL: http://llvm.org/viewvc/llvm-project?rev=174140&view=rev
Log:
Enable -fno-altivec, -mno-altivec for PowerPC.

Introduces these negation forms explicitly and uses them to control a new
"altivec" target feature for PowerPC.  This allows avoiding generating
Altivec instructions on processors that support Altivec.

The new test case verifies that the Altivec "lvx" instruction is not
used when -fno-altivec is present on the command line.

Added:
    cfe/trunk/test/CodeGen/ppc-no-altivec.c
Modified:
    cfe/trunk/include/clang/Driver/Options.td
    cfe/trunk/lib/Basic/Targets.cpp
    cfe/trunk/lib/Driver/Tools.cpp

Modified: cfe/trunk/include/clang/Driver/Options.td
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Driver/Options.td?rev=174140&r1=174139&r2=174140&view=diff
==============================================================================
--- cfe/trunk/include/clang/Driver/Options.td (original)
+++ cfe/trunk/include/clang/Driver/Options.td Thu Jan 31 20:14:03 2013
@@ -291,6 +291,7 @@ def faccess_control : Flag<["-"], "facce
 def fallow_unsupported : Flag<["-"], "fallow-unsupported">, Group<f_Group>;
 def faltivec : Flag<["-"], "faltivec">, Group<f_Group>, Flags<[CC1Option]>,
   HelpText<"Enable AltiVec vector initializer syntax">;
+def fno_altivec : Flag<["-"], "fno-altivec">, Group<f_Group>, Flags<[CC1Option]>;
 def fapple_kext : Flag<["-"], "fapple-kext">, Group<f_Group>, Flags<[CC1Option]>,
   HelpText<"Use Apple's kernel extensions ABI">;
 def fapple_pragma_pack : Flag<["-"], "fapple-pragma-pack">, Group<f_Group>, Flags<[CC1Option]>,
@@ -809,6 +810,7 @@ def m64 : Flag<["-"], "m64">, Group<m_Gr
 def mabi_EQ : Joined<["-"], "mabi=">, Group<m_Group>;
 def march_EQ : Joined<["-"], "march=">, Group<m_Group>;
 def maltivec : Flag<["-"], "maltivec">, Alias<faltivec>;
+def mno_altivec : Flag<["-"], "mno-altivec">, Alias<fno_altivec>;
 def mcmodel_EQ : Joined<["-"], "mcmodel=">, Group<m_Group>;
 def mconstant_cfstrings : Flag<["-"], "mconstant-cfstrings">, Group<clang_ignored_m_Group>;
 def mcpu_EQ : Joined<["-"], "mcpu=">, Group<m_Group>;

Modified: cfe/trunk/lib/Basic/Targets.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Basic/Targets.cpp?rev=174140&r1=174139&r2=174140&view=diff
==============================================================================
--- cfe/trunk/lib/Basic/Targets.cpp (original)
+++ cfe/trunk/lib/Basic/Targets.cpp Thu Jan 31 20:14:03 2013
@@ -711,6 +711,12 @@ public:
   virtual void getTargetDefines(const LangOptions &Opts,
                                 MacroBuilder &Builder) const;
 
+  virtual void getDefaultFeatures(llvm::StringMap<bool> &Features) const;
+
+  virtual bool setFeatureEnabled(llvm::StringMap<bool> &Features,
+                                 StringRef Name,
+                                 bool Enabled) const;
+
   virtual bool hasFeature(StringRef Feature) const;
   
   virtual void getGCCRegNames(const char * const *&Names,
@@ -907,7 +913,32 @@ void PPCTargetInfo::getTargetDefines(con
   if (defs & ArchDefinePwr6) {
     Builder.defineMacro("_ARCH_PWR5");
     Builder.defineMacro("_ARCH_PWR6");
+  }  
+}
+
+void PPCTargetInfo::getDefaultFeatures(llvm::StringMap<bool> &Features) const {
+  Features["altivec"] = llvm::StringSwitch<bool>(CPU)
+    .Case("7400", true)
+    .Case("g4", true)
+    .Case("7450", true)
+    .Case("g4+", true)
+    .Case("970", true)
+    .Case("g5", true)
+    .Case("pwr6", true)
+    .Case("pwr7", true)
+    .Case("ppc64", true)
+    .Default(false);
+}
+
+bool PPCTargetInfo::setFeatureEnabled(llvm::StringMap<bool> &Features,
+                                         StringRef Name,
+                                         bool Enabled) const {
+  if (Name == "altivec") {
+    Features[Name] = Enabled;
+    return true;
   }
+
+  return false;
 }
 
 bool PPCTargetInfo::hasFeature(StringRef Feature) const {

Modified: cfe/trunk/lib/Driver/Tools.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Driver/Tools.cpp?rev=174140&r1=174139&r2=174140&view=diff
==============================================================================
--- cfe/trunk/lib/Driver/Tools.cpp (original)
+++ cfe/trunk/lib/Driver/Tools.cpp Thu Jan 31 20:14:03 2013
@@ -1084,6 +1084,12 @@ void Clang::AddPPCTargetArgs(const ArgLi
     CmdArgs.push_back("-target-cpu");
     CmdArgs.push_back(Args.MakeArgString(TargetCPUName.c_str()));
   }
+
+  // Allow override of the Altivec feature.
+  if (Args.hasFlag(options::OPT_fno_altivec, options::OPT_faltivec, false)) {
+    CmdArgs.push_back("-target-feature");
+    CmdArgs.push_back("-altivec");
+  }
 }
 
 void Clang::AddSparcTargetArgs(const ArgList &Args,

Added: cfe/trunk/test/CodeGen/ppc-no-altivec.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/ppc-no-altivec.c?rev=174140&view=auto
==============================================================================
--- cfe/trunk/test/CodeGen/ppc-no-altivec.c (added)
+++ cfe/trunk/test/CodeGen/ppc-no-altivec.c Thu Jan 31 20:14:03 2013
@@ -0,0 +1,12 @@
+// REQUIRES: ppc64-registered-target
+// RUN: %clang_cc1 %s -triple=powerpc64-unknown-linux-gnu -S -o - | FileCheck %s
+
+typedef char v8qi  __attribute__((vector_size (8)));
+
+extern v8qi x, y;
+
+v8qi foo (void) {
+  return x + y;
+}
+
+// CHECK-NOT: lvx