Index: lib/Target/X86/X86ISelDAGToDAG.cpp =================================================================== --- lib/Target/X86/X86ISelDAGToDAG.cpp +++ lib/Target/X86/X86ISelDAGToDAG.cpp @@ -2277,6 +2277,27 @@ switch (Opcode) { default: break; + case ISD::BRIND: { + if (Subtarget->isTargetNaCl()) + // NaCl has its own pass where jmp %r32 are converted to jmp %r64. We + // leave the instruction alone. + break; + if (Subtarget->isTarget64BitILP32()) { + // Converts a 32-bit register to a 64-bit, zero-extended version of + // it. This is needed because x86-64 can do many things, but jmp %r32 + // ain't one of them. + const SDValue &Target = Node->getOperand(1); + assert(Target.getSimpleValueType() == llvm::MVT::i32); + SDValue ZextTarget = CurDAG->getZExtOrTrunc(Target, dl, EVT(MVT::i64)); + SDValue Brind = CurDAG->getNode(ISD::BRIND, dl, MVT::Other, + Node->getOperand(0), ZextTarget); + ReplaceUses(SDValue(Node, 0), Brind); + SelectCode(ZextTarget.getNode()); + SelectCode(Brind.getNode()); + return nullptr; + } + break; + } case ISD::INTRINSIC_W_CHAIN: { unsigned IntNo = cast(Node->getOperand(1))->getZExtValue(); switch (IntNo) { Index: test/CodeGen/X86/x32-indirectbr.ll =================================================================== --- /dev/null +++ test/CodeGen/X86/x32-indirectbr.ll @@ -0,0 +1,26 @@ +; RUN: llc < %s -mtriple=x86_64-none-none-gnux32 -mcpu=generic | FileCheck %s +; RUN: llc < %s -mtriple=x86_64-none-none-gnux32 -mcpu=generic -fast-isel | FileCheck %s +; Bug 22859 +; +; x32 pointers are 32-bits wide. x86-64 indirect branches use the full 64-bit +; registers. Therefore, x32 CodeGen needs to zero extend indirectbr's target to +; 64-bit. + +define i8 @test1() nounwind ssp { +entry: + %0 = select i1 undef, ; [#uses=1] + i8* blockaddress(@test1, %bb), + i8* blockaddress(@test1, %bb6) + indirectbr i8* %0, [label %bb, label %bb6] +bb: ; preds = %entry + ret i8 1 + +bb6: ; preds = %entry + ret i8 2 +} +; CHECK-LABEL: @test1 +; We are looking for a movl ???, %r32 followed by a 64-bit jmp through the +; same register. +; CHECK: movl {{.*}}, %{{e|r}}[[REG:.[^d]*]]{{d?}} +; CHECK-NEXT: jmpq *%r[[REG]] +