Commit c4b6274d authored by Hans Wennborg's avatar Hans Wennborg
Browse files

Merging r242239: 

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r242239 | hfinkel | 2015-07-14 15:53:11 -0700 (Tue, 14 Jul 2015) | 4 lines

[PowerPC] Support symbolic targets in patchpoints

Follow-up r235483, with the corresponding support in PPC. We use a regular call
for symbolic targets (because they're much cheaper than indirect calls).
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llvm-svn: 242325
parent 284f6ec1

llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp

+71 −57
Original line number Diff line number Diff line
@@ -363,8 +363,12 @@ void PPCAsmPrinter::LowerPATCHPOINT(MCStreamer &OutStreamer, StackMaps &SM, 
  SM.recordPatchPoint(MI);

  PatchPointOpers Opers(&MI);



  int64_t CallTarget = Opers.getMetaOper(PatchPointOpers::TargetPos).getImm();

  unsigned EncodedBytes = 0;

  const MachineOperand &CalleeMO =

    Opers.getMetaOper(PatchPointOpers::TargetPos);



  if (CalleeMO.isImm()) {

    int64_t CallTarget = Opers.getMetaOper(PatchPointOpers::TargetPos).getImm();

    if (CallTarget) {

      assert((CallTarget & 0xFFFFFFFFFFFF) == CallTarget &&

             "High 16 bits of call target should be zero.");
@@ -399,8 +403,8 @@ void PPCAsmPrinter::LowerPATCHPOINT(MCStreamer &OutStreamer, StackMaps &SM, 
      ++EncodedBytes;





    // If we're on ELFv1, then we need to load the actual function pointer from

    // the function descriptor.

      // If we're on ELFv1, then we need to load the actual function pointer

      // from the function descriptor.

      if (!Subtarget->isELFv2ABI()) {

	// Load the new TOC pointer and the function address, but not r11

	// (needing this is rare, and loading it here would prevent passing it
@@ -417,7 +421,8 @@ void PPCAsmPrinter::LowerPATCHPOINT(MCStreamer &OutStreamer, StackMaps &SM, 
        ++EncodedBytes;

      }



    EmitToStreamer(OutStreamer, MCInstBuilder(PPC::MTCTR8).addReg(ScratchReg));

      EmitToStreamer(OutStreamer, MCInstBuilder(PPC::MTCTR8)

                                      .addReg(ScratchReg));

      ++EncodedBytes;

      EmitToStreamer(OutStreamer, MCInstBuilder(PPC::BCTRL8));

      ++EncodedBytes;
@@ -429,6 +434,15 @@ void PPCAsmPrinter::LowerPATCHPOINT(MCStreamer &OutStreamer, StackMaps &SM, 
                                      .addReg(PPC::X1));

      ++EncodedBytes;

    }

  } else if (CalleeMO.isGlobal()) {

    const GlobalValue *GValue = CalleeMO.getGlobal();

    MCSymbol *MOSymbol = getSymbol(GValue);

    const MCExpr *SymVar = MCSymbolRefExpr::create(MOSymbol, OutContext);



    EmitToStreamer(OutStreamer, MCInstBuilder(PPC::BL8_NOP)

                                    .addExpr(SymVar));

    EncodedBytes += 2;

  }



  // Each instruction is 4 bytes.

  EncodedBytes *= 4;

llvm/test/CodeGen/PowerPC/ppc64-patchpoint.ll

+15 −0
Original line number Diff line number Diff line
@@ -103,6 +103,21 @@ entry: 
  ret void

}



; Trivial symbolic patchpoint codegen.



declare i64 @foo(i64 %p1, i64 %p2)

define i64 @trivial_symbolic_patchpoint_codegen(i64 %p1, i64 %p2) {

entry:

; CHECK-LABEL: trivial_symbolic_patchpoint_codegen:

; CHECK:       bl foo

; CHECK-NEXT:  nop

; CHECK-NEXT:  nop

; CHECK-NOT:   nop

; CHECK:       blr

  %result = tail call i64 (i64, i32, i8*, i32, ...) @llvm.experimental.patchpoint.i64(i64 9, i32 12, i8* bitcast (i64 (i64, i64)* @foo to i8*), i32 2, i64 %p1, i64 %p2)

  ret i64 %result

}



declare void @llvm.experimental.stackmap(i64, i32, ...)

declare void @llvm.experimental.patchpoint.void(i64, i32, i8*, i32, ...)

declare i64 @llvm.experimental.patchpoint.i64(i64, i32, i8*, i32, ...)