diff --git a/lib/Target/PowerPC/PPCAsmPrinter.cpp b/lib/Target/PowerPC/PPCAsmPrinter.cpp index 6af30720f25..8d350a40136 100644 --- a/lib/Target/PowerPC/PPCAsmPrinter.cpp +++ b/lib/Target/PowerPC/PPCAsmPrinter.cpp @@ -679,6 +679,25 @@ void PPCAsmPrinter::EmitInstruction(const MachineInstr *MI) { OutStreamer.EmitRawText(StringRef("\tmsync")); return; } + break; + case PPC::LD: + case PPC::STD: + case PPC::LWA: { + // Verify alignment is legal, so we don't create relocations + // that can't be supported. + // FIXME: This test is currently disabled for Darwin. The test + // suite shows a handful of test cases that fail this check for + // Darwin. Those need to be investigated before this sanity test + // can be enabled for those subtargets. + if (!Subtarget.isDarwin()) { + unsigned OpNum = (MI->getOpcode() == PPC::STD) ? 2 : 1; + const MachineOperand &MO = MI->getOperand(OpNum); + if (MO.isGlobal() && MO.getGlobal()->getAlignment() < 4) + llvm_unreachable("Global must be word-aligned for LD, STD, LWA!"); + } + // Now process the instruction normally. + break; + } } LowerPPCMachineInstrToMCInst(MI, TmpInst, *this); diff --git a/lib/Target/PowerPC/PPCISelDAGToDAG.cpp b/lib/Target/PowerPC/PPCISelDAGToDAG.cpp index f8d990cee62..cc4478b1c29 100644 --- a/lib/Target/PowerPC/PPCISelDAGToDAG.cpp +++ b/lib/Target/PowerPC/PPCISelDAGToDAG.cpp @@ -1530,6 +1530,14 @@ void PPCDAGToDAGISel::PostprocessISelDAG() { if (GlobalAddressSDNode *GA = dyn_cast(ImmOpnd)) { SDLoc dl(GA); const GlobalValue *GV = GA->getGlobal(); + // We can't perform this optimization for data whose alignment + // is insufficient for the instruction encoding. + if (GV->getAlignment() < 4 && + (StorageOpcode == PPC::LD || StorageOpcode == PPC::STD || + StorageOpcode == PPC::LWA)) { + DEBUG(dbgs() << "Rejected this candidate for alignment.\n\n"); + continue; + } ImmOpnd = CurDAG->getTargetGlobalAddress(GV, dl, MVT::i64, 0, Flags); } else if (ConstantPoolSDNode *CP = dyn_cast(ImmOpnd)) { diff --git a/test/CodeGen/PowerPC/reloc-align.ll b/test/CodeGen/PowerPC/reloc-align.ll new file mode 100644 index 00000000000..bd5c4d6e5e0 --- /dev/null +++ b/test/CodeGen/PowerPC/reloc-align.ll @@ -0,0 +1,34 @@ +; RUN: llc -mcpu=pwr7 -O1 < %s | FileCheck %s + +; This test verifies that the peephole optimization of address accesses +; does not produce a load or store with a relocation that can't be +; satisfied for a given instruction encoding. Reduced from a test supplied +; by Hal Finkel. + +target datalayout = "E-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-f128:128:128-v128:128:128-n32:64" +target triple = "powerpc64-unknown-linux-gnu" + +%struct.S1 = type { [8 x i8] } + +@main.l_1554 = internal global { i8, i8, i8, i8, i8, i8, i8, i8 } { i8 -1, i8 -6, i8 57, i8 62, i8 -48, i8 0, i8 58, i8 80 }, align 1 + +; Function Attrs: nounwind readonly +define signext i32 @main() #0 { +entry: + %call = tail call fastcc signext i32 @func_90(%struct.S1* byval bitcast ({ i8, i8, i8, i8, i8, i8, i8, i8 }* @main.l_1554 to %struct.S1*)) +; CHECK-NOT: ld {{[0-9]+}}, main.l_1554@toc@l + ret i32 %call +} + +; Function Attrs: nounwind readonly +define internal fastcc signext i32 @func_90(%struct.S1* byval nocapture %p_91) #0 { +entry: + %0 = bitcast %struct.S1* %p_91 to i64* + %bf.load = load i64* %0, align 1 + %bf.shl = shl i64 %bf.load, 26 + %bf.ashr = ashr i64 %bf.shl, 54 + %bf.cast = trunc i64 %bf.ashr to i32 + ret i32 %bf.cast +} + +attributes #0 = { nounwind readonly "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf"="true" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "unsafe-fp-math"="false" "use-soft-float"="false" }