user/llvm6: Add Secure PLT support to PowerPC

1 files changed, 208 insertions, 0 deletions

diff --git a/user/llvm6/secure-plt.patch b/user/llvm6/secure-plt.patch
new file mode 100644
index 000000000..e8af33d87
--- /dev/null
+++ b/user/llvm6/secure-plt.patch
@@ -0,0 +1,208 @@
+Index: llvm/lib/Target/PowerPC/PPC.td
+===================================================================
+--- llvm/lib/Target/PowerPC/PPC.td
++++ llvm/lib/Target/PowerPC/PPC.td
+@@ -119,6 +119,8 @@
+                               [FeatureBookE]>;
+ def FeatureE500      : SubtargetFeature<"e500", "IsE500", "true",
+                                         "Enable E500/E500mc instructions">;
++def FeatureSecurePlt : SubtargetFeature<"secure-plt","SecurePlt", "true",
++                                        "Enable secure plt mode">;
+ def FeaturePPC4xx    : SubtargetFeature<"ppc4xx", "IsPPC4xx", "true",
+                                         "Enable PPC 4xx instructions">;
+ def FeaturePPC6xx    : SubtargetFeature<"ppc6xx", "IsPPC6xx", "true",
+Index: llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
+===================================================================
+--- llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
++++ llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
+@@ -563,33 +563,63 @@
+     // Transform %rd = UpdateGBR(%rt, %ri)
+     // Into: lwz %rt, .L0$poff - .L0$pb(%ri)
+     //       add %rd, %rt, %ri
++    // or into (if secure plt mode is on):
++    //       addis r30, r30, .LTOC - .L0$pb@ha
++    //       addi r30, r30, .LTOC - .L0$pb@l
+     // Get the offset from the GOT Base Register to the GOT
+     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, isDarwin);
+-    MCSymbol *PICOffset =
+-      MF->getInfo<PPCFunctionInfo>()->getPICOffsetSymbol();
+-    TmpInst.setOpcode(PPC::LWZ);
+-    const MCExpr *Exp =
+-      MCSymbolRefExpr::create(PICOffset, MCSymbolRefExpr::VK_None, OutContext);
+-    const MCExpr *PB =
+-      MCSymbolRefExpr::create(MF->getPICBaseSymbol(),
+-                              MCSymbolRefExpr::VK_None,
+-                              OutContext);
+-    const MCOperand TR = TmpInst.getOperand(1);
+-    const MCOperand PICR = TmpInst.getOperand(0);
++    if (Subtarget->isSecurePlt() && isPositionIndependent() ) {
++      unsigned PICR = TmpInst.getOperand(0).getReg();
++      MCSymbol *LTOCSymbol = OutContext.getOrCreateSymbol(StringRef(".LTOC"));
++      const MCExpr *PB =
++        MCSymbolRefExpr::create(MF->getPICBaseSymbol(),
++                                OutContext);
+ 
+-    // Step 1: lwz %rt, .L$poff - .L$pb(%ri)
+-    TmpInst.getOperand(1) =
+-        MCOperand::createExpr(MCBinaryExpr::createSub(Exp, PB, OutContext));
+-    TmpInst.getOperand(0) = TR;
+-    TmpInst.getOperand(2) = PICR;
+-    EmitToStreamer(*OutStreamer, TmpInst);
++      const MCExpr *LTOCDeltaExpr =
++        MCBinaryExpr::createSub(MCSymbolRefExpr::create(LTOCSymbol, OutContext),
++                                PB, OutContext);
+ 
+-    TmpInst.setOpcode(PPC::ADD4);
+-    TmpInst.getOperand(0) = PICR;
+-    TmpInst.getOperand(1) = TR;
+-    TmpInst.getOperand(2) = PICR;
+-    EmitToStreamer(*OutStreamer, TmpInst);
+-    return;
++      const MCExpr *LTOCDeltaHi =
++        PPCMCExpr::createHa(LTOCDeltaExpr, false, OutContext);
++      EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADDIS)
++                                   .addReg(PICR)
++                                   .addReg(PICR)
++                                   .addExpr(LTOCDeltaHi));
++
++      const MCExpr *LTOCDeltaLo =
++        PPCMCExpr::createLo(LTOCDeltaExpr, false, OutContext);
++      EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADDI)
++                                   .addReg(PICR)
++                                   .addReg(PICR)
++                                   .addExpr(LTOCDeltaLo));
++      return;
++    } else {
++      MCSymbol *PICOffset =
++        MF->getInfo<PPCFunctionInfo>()->getPICOffsetSymbol();
++      TmpInst.setOpcode(PPC::LWZ);
++      const MCExpr *Exp =
++        MCSymbolRefExpr::create(PICOffset, MCSymbolRefExpr::VK_None, OutContext);
++      const MCExpr *PB =
++        MCSymbolRefExpr::create(MF->getPICBaseSymbol(),
++                                MCSymbolRefExpr::VK_None,
++                                OutContext);
++      const MCOperand TR = TmpInst.getOperand(1);
++      const MCOperand PICR = TmpInst.getOperand(0);
++
++      // Step 1: lwz %rt, .L$poff - .L$pb(%ri)
++      TmpInst.getOperand(1) =
++          MCOperand::createExpr(MCBinaryExpr::createSub(Exp, PB, OutContext));
++      TmpInst.getOperand(0) = TR;
++      TmpInst.getOperand(2) = PICR;
++      EmitToStreamer(*OutStreamer, TmpInst);
++
++      TmpInst.setOpcode(PPC::ADD4);
++      TmpInst.getOperand(0) = PICR;
++      TmpInst.getOperand(1) = TR;
++      TmpInst.getOperand(2) = PICR;
++      EmitToStreamer(*OutStreamer, TmpInst);
++      return;
++    }
+   }
+   case PPC::LWZtoc: {
+     // Transform %r3 = LWZtoc @min1, %r2
+@@ -1233,7 +1263,7 @@
+ 
+   if (!Subtarget->isPPC64()) {
+     const PPCFunctionInfo *PPCFI = MF->getInfo<PPCFunctionInfo>();
+-    if (PPCFI->usesPICBase()) {
++    if (PPCFI->usesPICBase() && !Subtarget->isSecurePlt()) {
+       MCSymbol *RelocSymbol = PPCFI->getPICOffsetSymbol();
+       MCSymbol *PICBase = MF->getPICBaseSymbol();
+       OutStreamer->EmitLabel(RelocSymbol);
+Index: llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
+===================================================================
+--- llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
++++ llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
+@@ -4001,6 +4001,27 @@
+       return;
+     break;
+ 
++  case PPCISD::CALL: {
++    const Module *M = MF->getFunction().getParent();
++
++    if (PPCLowering->getPointerTy(CurDAG->getDataLayout()) != MVT::i32 ||
++        !PPCSubTarget->isSecurePlt() || !PPCSubTarget->isTargetELF() ||
++        M->getPICLevel() == PICLevel::SmallPIC)
++      break;
++
++    SDValue Op = N->getOperand(1);
++
++    if (GlobalAddressSDNode *GA = dyn_cast<GlobalAddressSDNode>(Op)) {
++      if (GA->getTargetFlags() == PPCII::MO_PLT)
++        getGlobalBaseReg();
++    }
++    else if (ExternalSymbolSDNode *ES = dyn_cast<ExternalSymbolSDNode>(Op)) {
++      if (ES->getTargetFlags() == PPCII::MO_PLT)
++        getGlobalBaseReg();
++    }
++  }
++    break;
++
+   case PPCISD::GlobalBaseReg:
+     ReplaceNode(N, getGlobalBaseReg());
+     return;
+Index: llvm/lib/Target/PowerPC/PPCMCInstLower.cpp
+===================================================================
+--- llvm/lib/Target/PowerPC/PPCMCInstLower.cpp
++++ llvm/lib/Target/PowerPC/PPCMCInstLower.cpp
+@@ -107,10 +107,20 @@
+       break;
+   }
+ 
+-  if (MO.getTargetFlags() == PPCII::MO_PLT)
++ if (MO.getTargetFlags() == PPCII::MO_PLT)
+     RefKind = MCSymbolRefExpr::VK_PLT;
+ 
++  const MachineFunction *MF = MO.getParent()->getParent()->getParent();
++  const PPCSubtarget *Subtarget = &(MF->getSubtarget<PPCSubtarget>());
++  const TargetMachine &TM = Printer.TM;
+   const MCExpr *Expr = MCSymbolRefExpr::create(Symbol, RefKind, Ctx);
++  // -msecure-plt option works only in PIC mode. If secure plt mode
++  // is on add 32768 to symbol.
++  if (Subtarget->isSecurePlt() && TM.isPositionIndependent() &&
++      MO.getTargetFlags() == PPCII::MO_PLT)
++    Expr = MCBinaryExpr::createAdd(Expr,
++                                   MCConstantExpr::create(32768, Ctx),
++                                   Ctx);
+ 
+   if (!MO.isJTI() && MO.getOffset())
+     Expr = MCBinaryExpr::createAdd(Expr,
+Index: llvm/lib/Target/PowerPC/PPCSubtarget.h
+===================================================================
+--- llvm/lib/Target/PowerPC/PPCSubtarget.h
++++ llvm/lib/Target/PowerPC/PPCSubtarget.h
+@@ -133,6 +133,7 @@
+   bool HasFloat128;
+   bool IsISA3_0;
+   bool UseLongCalls;
++  bool SecurePlt;
+ 
+   POPCNTDKind HasPOPCNTD;
+ 
+@@ -255,6 +256,7 @@
+   bool hasOnlyMSYNC() const { return HasOnlyMSYNC; }
+   bool isPPC4xx() const { return IsPPC4xx; }
+   bool isPPC6xx() const { return IsPPC6xx; }
++  bool isSecurePlt() const {return SecurePlt; }
+   bool isE500() const { return IsE500; }
+   bool isFeatureMFTB() const { return FeatureMFTB; }
+   bool isDeprecatedDST() const { return DeprecatedDST; }
+Index: llvm/test/CodeGen/PowerPC/ppc32-pic-large.ll
+===================================================================
+--- llvm/test/CodeGen/PowerPC/ppc32-pic-large.ll
++++ llvm/test/CodeGen/PowerPC/ppc32-pic-large.ll
+@@ -1,4 +1,5 @@
+ ; RUN: llc < %s -mtriple=powerpc-unknown-linux-gnu -relocation-model=pic | FileCheck -check-prefix=LARGE-BSS %s
++; RUN: llc < %s -mtriple=powerpc-unknown-linux-gnu -mattr=+secure-plt -relocation-model=pic | FileCheck -check-prefix=LARGE-SECUREPLT %s
+ @bar = common global i32 0, align 4
+ 
+ declare i32 @call_foo(i32, ...)
+@@ -29,3 +30,6 @@
+ ; LARGE-BSS:       [[VREF]]:
+ ; LARGE-BSS-NEXT:     .p2align 2
+ ; LARGE-BSS-NEXT:    .long bar
++; LARGE-SECUREPLT:   addis 30, 30, .LTOC-.L0$pb@ha
++; LARGE-SECUREPLT:   addi 30, 30, .LTOC-.L0$pb@l
++; LARGE-SECUREPLT:   bl call_foo@PLT+32768