[CodeGen] Make branch funnels pass the machine verifier

We previously marked all the tests with branch funnels as
`-verify-machineinstrs=0`.

This is an attempt to fix it.

1) `ICALL_BRANCH_FUNNEL` has no defs. Mark it as `let OutOperandList =
(outs)`

2) After that we hit an assert: ``` Assertion failed: (Op.getValueType()
!= MVT::Other && Op.getValueType() != MVT::Glue && "Chain and glue
operands should occur at end of operand list!"), function AddOperand,
file
/Users/francisvm/llvm/llvm/lib/CodeGen/SelectionDAG/InstrEmitter.cpp,
line 461.  ```

The chain operand was added at the beginning of the operand list. Move
that to the end.

3) After that we hit another verifier issue in the pseudo expansion
where the registers used in the cmps and jmps are not added to the
livein lists. Add the `EFLAGS` to all the new MBBs that we create.

PR39436

Differential Review: https://reviews.llvm.org/D54155

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@365058 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Target/Target.td

@@ -1207,7 +1207,7 @@ def FENTRY_CALL : StandardPseudoInstruction {
   let hasSideEffects = 1;
 }
 def ICALL_BRANCH_FUNNEL : StandardPseudoInstruction {
-  let OutOperandList = (outs unknown:$dst);
+  let OutOperandList = (outs);
   let InOperandList = (ins variable_ops);
   let AsmString = "";
   let hasSideEffects = 1;

lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

@@ -6746,7 +6746,6 @@ void SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I,
 
   case Intrinsic::icall_branch_funnel: {
     SmallVector<SDValue, 16> Ops;
-    Ops.push_back(DAG.getRoot());
     Ops.push_back(getValue(I.getArgOperand(0)));
 
     int64_t Offset;
@@ -6789,6 +6788,7 @@ void SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I,
       Ops.push_back(T.Target);
     }
 
+    Ops.push_back(DAG.getRoot()); // Chain
     SDValue N(DAG.getMachineNode(TargetOpcode::ICALL_BRANCH_FUNNEL,
                                  getCurSDLoc(), MVT::Other, Ops),
               0);

lib/Target/X86/X86ExpandPseudo.cpp

@@ -87,6 +87,8 @@ void X86ExpandPseudo::ExpandICallBranchFunnel(
   const GlobalValue *CombinedGlobal = JTInst->getOperand(1).getGlobal();
 
   auto CmpTarget = [&](unsigned Target) {
+    if (Selector.isReg())
+      MBB->addLiveIn(Selector.getReg());
     BuildMI(*MBB, MBBI, DL, TII->get(X86::LEA64r), X86::R11)
         .addReg(X86::RIP)
         .addImm(1)
@@ -102,6 +104,8 @@ void X86ExpandPseudo::ExpandICallBranchFunnel(
   auto CreateMBB = [&]() {
     auto *NewMBB = MF->CreateMachineBasicBlock(BB);
     MBB->addSuccessor(NewMBB);
+    if (!MBB->isLiveIn(X86::EFLAGS))
+      MBB->addLiveIn(X86::EFLAGS);
     return NewMBB;
   };
 

test/CodeGen/X86/icall-branch-funnel.ll

@@ -1,5 +1,4 @@
-; FIXME: Fix machine verifier issues and remove -verify-machineinstrs=0. PR39436.
-; RUN: llc -mtriple=x86_64-unknown-linux -verify-machineinstrs=0 < %s | FileCheck %s
+; RUN: llc -mtriple=x86_64-unknown-linux < %s | FileCheck %s
 
 @g = external global i8
 

test/ThinLTO/X86/cfi-devirt.ll

@@ -5,9 +5,7 @@
 ; RUN: opt -thinlto-bc -thinlto-split-lto-unit -o %t.o %s
 
 ; Legacy PM
-; FIXME: Fix machine verifier issues and remove -verify-machineinstrs=0. PR39436.
 ; RUN: llvm-lto2 run %t.o -save-temps -pass-remarks=. \
-; RUN:   -verify-machineinstrs=0 \
 ; RUN:   -o %t3 \
 ; RUN:   -r=%t.o,test,px \
 ; RUN:   -r=%t.o,_ZN1A1nEi,p \
@@ -24,9 +22,7 @@
 ; RUN: llvm-dis %t3.1.4.opt.bc -o - | FileCheck %s --check-prefix=CHECK-IR
 
 ; New PM
-; FIXME: Fix machine verifier issues and remove -verify-machineinstrs=0. PR39436.
 ; RUN: llvm-lto2 run %t.o -save-temps -use-new-pm -pass-remarks=. \
-; RUN:   -verify-machineinstrs=0 \
 ; RUN:   -o %t3 \
 ; RUN:   -r=%t.o,test,px \
 ; RUN:   -r=%t.o,_ZN1A1nEi,p \
@@ -50,7 +46,6 @@
 ; to ensure it is being caught in the thin link.
 ; RUN: opt -thinlto-bc -o %t2.o %S/Inputs/empty.ll
 ; RUN: not llvm-lto2 run %t.o %t2.o -thinlto-distributed-indexes \
-; RUN:   -verify-machineinstrs=0 \
 ; RUN:   -o %t3 \
 ; RUN:   -r=%t.o,test,px \
 ; RUN:   -r=%t.o,_ZN1A1nEi,p \

test/ThinLTO/X86/devirt-after-icp.ll

@@ -45,9 +45,7 @@
 ; RUN: opt -thinlto-bc -thinlto-split-lto-unit -o %t.o %s
 
 ; Legacy PM
-; FIXME: Fix machine verifier issues and remove -verify-machineinstrs=0. PR39436.
 ; RUN: llvm-lto2 run %t.o -save-temps -pass-remarks=. \
-; RUN:   -verify-machineinstrs=0 \
 ; RUN:   -o %t3 \
 ; RUN:   -r=%t.o,_Z3bazP1A,px \
 ; RUN:   -r=%t.o,_ZN1A3fooEv, \
@@ -65,9 +63,7 @@
 ; RUN: llvm-dis %t3.1.4.opt.bc -o - | FileCheck %s --check-prefix=CHECK-IR
 
 ; New PM
-; FIXME: Fix machine verifier issues and remove -verify-machineinstrs=0. PR39436.
 ; RUN: llvm-lto2 run %t.o -save-temps -use-new-pm -pass-remarks=. \
-; RUN:   -verify-machineinstrs=0 \
 ; RUN:   -o %t3 \
 ; RUN:   -r=%t.o,_Z3bazP1A,px \
 ; RUN:   -r=%t.o,_ZN1A3fooEv, \