[SelectionDAG] make INLINEASM_BR use MachineBasicBlocks instead of BlockAddresses

[nickdesaulniers]

Summary

As part of re-architecting callbr to no longer use blockaddresses
(https://reviews.llvm.org/D129288), we don't really need them in MIR.
They make comparing MachineBasicBlocks of indirect targets during
MachineVerifier a PITA.

Suggested by @efriedma from the discussion:
https://reviews.llvm.org/D130290#3669531

[nickdesaulniers]

llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp

3639–3643 ↗

(On Diff #446658)

I'm going to test these out, too. But RFC; comments welcome.

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

5371–5372

Not sure this is quite right, but also not sure what it should be. Maybe the reviewers do?

llvm/test/CodeGen/X86/tail-dup-asm-goto.ll

10–11

I think I should pre-commit an initial run of update_mir_test_checks.py on this...

[nickdesaulniers]

• rebase on top of 0ccb6da725bad797f576713613f8368f7f52290c

llvm/test/CodeGen/X86/tail-dup-asm-goto.ll

10–11

0ccb6da725bad797f576713613f8368f7f52290c

[nickdesaulniers]

• SelectionDAGBuilder::visitCallBr() no longer needs to call MachineBasicBlock::setHasAddressTaken()

[nickdesaulniers]

We might also be able to remove some of the handling in
EmitGCCInlineAsmStr <llvm/lib/CodeGen/AsmPrinter/AsmPrinterInlineAsm.cpp>

• commit 83d690a14980 ("Don't rely on 'l'(ell) modifiers to indicate a label reference")
• commit 1b104388752f ("[MC] Don't recreate a label if it's already used")

[arsenm]

llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp

3641–3644 ↗

(On Diff #446666)

Comments can be removed after D130323?

[barannikov88]

llvm/test/CodeGen/AArch64/callbr-asm-label.ll

9–10

I'm a bit out of context, so the question might be silly, sorry.
Shouldn't this temporary label no longer be emitted? It used to be referenced, but no longer is.

[nikic]

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

5371–5372

BA has an i8* type, so can directly use that?

5374

This is a roundabout way of saying cast<CallBrInst>(&Call)->getIndirectDest(LabelNo) -- unless the fact that a BlockAddress on the IR level is created is still important for something?

[nickdesaulniers]

llvm/test/CodeGen/AArch64/callbr-asm-label.ll

9–10

It's not a silly question; it's a great question.

I've been trying to track that down, as I don't know the answer myself.

IIRC, we did previously have an issue with labels disappearing out from under us. @void solved that in either

• commit 83d690a14980 ("Don't rely on 'l'(ell) modifiers to indicate a label reference")
• commit 1b104388752f ("[MC] Don't recreate a label if it's already used")

I've already found that the latter is no longer necessary, hence https://reviews.llvm.org/D130323, but that's not what was retaining these additional symbols.

(or maybe it was a third commit, maybe 79176a2542d03107b90613c84f18ccba41ad8fa8?)

So I would like to find the answer to this question, and perhaps remove the duplicate labels. But it would be a minor cosmetic fix; I'm not going to spend too much time on it since this patch is just a chain in a longer series that we're ultimately trying to fix. Fixing duplicate labels is nice to have, but slightly orthogonal.

[nickdesaulniers]

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

5371–5372

Type::getInt8PtrTy seems to cause crashes...cant tell what type is actually being used; everything looks like opaque ptrs...

[nickdesaulniers]

• use CallBrInst::getIndirectDest rather than BlockAddress::getBasicBlock for OpInfo.CallOperandVal

[nickdesaulniers]

• prefer MachineBasicBlock::setLabelMustBeEmitted in SelectionDAGBuilder::visitCallBr over an additional check for MachineBasicBlock::isInlineAsmBrIndirectTarget in AsmPrinter::shouldEmitLabelForBasicBlock

[nickdesaulniers]

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

5374

Actually, it might be for some of the follow up reverts. I wonder if this is what's creating all of the .Ltmp labels that no longer seem necessary...

[nickdesaulniers]

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

5371–5372

branch-folder is messing something up...

[nickdesaulniers]

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

5371–5372

ahoy! Both TailDuplicator and BranchFolding were relying on whether an MBB has its address taken. After this change, they wont, so those cases additionally need to check for isInlineAsmBrIndirectTarget. With that added, we're working AND the .Ltmp labels are gone (good)! Now just to clean up the test churn after lunch, but I think this will all work and look nice. Stay tuned.

[nickdesaulniers]

• get rid of the stupid .Ltmp double labels

[nickdesaulniers]

Ok, this is ready for review/testing. It's part of a series:

1. https://reviews.llvm.org/D130316
2. https://reviews.llvm.org/D130323
3. https://reviews.llvm.org/D130391

Then 4 (https://reviews.llvm.org/D130290) which I will rebase once this lands.

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

5371–5372

The last wart on an otherwise great simplification is getting the context for Type::getInt8PtrTy. Thoughts on how I can improve this?

[nikic]

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

5371–5372

I think you can just use getProgramPointerTy(DL) to directly get the right MVT. No need to indirect via IR types.

You should also be able to drop the getBlockAddressForIndirectDest() method.

[barannikov88]

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

5374

Debugging leftover, I guess?

[barannikov88]

llvm/test/CodeGen/X86/inline-asm-pic.ll

34

The one here remains.

[nickdesaulniers]

• use getProgramPointerTy, del CallBrInst::getBlockAddressForIndirectDest

[nickdesaulniers]

llvm/test/CodeGen/X86/inline-asm-pic.ll

34

This is expected. You'll notice that it's address is taken by the blockaddress constant in @y (Line 57).

My change stops using blockaddress for callbr. It doesn't remove blockaddress from the language; test @y is testing the "address of a label" as an input to the inline asm, which is distinct from the label list used in asm goto.

That said, thanks for triple checking!

[barannikov88]

llvm/test/CodeGen/X86/inline-asm-pic.ll

34

Nope, line 57 is a different test.
Anyway, this was just an observation and not a suggestion to look into this specific case. Most parasitic labels are gone, so this is probably something X86-specific, which I believe is out of scope of this patch series.

[nikic]

I like the change, but I'm not familiar enough with the backend to fully understand the implications. The main thing I'd worry about is that more places that currently check hasAddressTaken() would also need to check isInlineAsmBrIndirectTarget(). E.g. I see more calls to the method in IfConversion. (Would it make sense to stop using blockaddresses, but still mark the MBBs are address-taken?)

[nickdesaulniers]

In D130316#3673721, @nikic wrote:

I like the change, but I'm not familiar enough with the backend to fully understand the implications. The main thing I'd worry about is that more places that currently check hasAddressTaken() would also need to check isInlineAsmBrIndirectTarget(). E.g. I see more calls to the method in IfConversion. (Would it make sense to stop using blockaddresses, but still mark the MBBs are address-taken?)

It does seem risky and orthogonal to the goal of this patch. Let me break out the s/setHasAddressTaken/setLabelMustBeEmitted/ change into a distinct child patch. BRB while I rechurn the test changes, again.

[nickdesaulniers]

• keep setHasAddressTaken, just add setLabelMustBeEmitted

[nickdesaulniers]

In D130316#3673721, @nikic wrote:

I like the change, but I'm not familiar enough with the backend to fully understand the implications. The main thing I'd worry about is that more places that currently check hasAddressTaken() would also need to check isInlineAsmBrIndirectTarget(). E.g. I see more calls to the method in IfConversion. (Would it make sense to stop using blockaddresses, but still mark the MBBs are address-taken?)

Done; PTAL. Sorry for the delay, was offline most of last week.

[arsenm]

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

5371–5372

getProgramPointerTy is correct but I would expect taking the type directly from the IR would be better (in principle we could have individual functions with a different address space from the DL one, although I think that's currently unsupported)

[nickdesaulniers]

• rebase, remove setting OpInfo.ConstraintVT

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

5371–5372

FWICT, this assignment is no longer necessary. Removing it, as it doesn't affect tests.

[nickdesaulniers]

bumping for review

[void]

This patch seems pretty straight-forward, so I'll add my LGTM here. Please feel free to override that if other reviewers are less sure. :-)

llvm/test/CodeGen/AArch64/callbr-asm-label.ll

9–10

My memory is hazy on the details, but there were a number of issues with inline asm and labels when dealing with block addresses and basic blocks. The changes you mentioned are large hammers, but *seemed* necessary. There may be better ways to handle the label issue though.

[efriedma]

LGTM

I just merged D124697; I expect rebasing this on top of that should be trivial, but feel free to ask for another round of review if it isn't for some reason.

[nickdesaulniers]

• rebase, update mir tests to remove ir-block-address-taken MBB annotation

llvm/include/llvm/IR/Instructions.h

public:
   void setSuccessor(unsigned i, BasicBlock *NewSucc) {
     assert(i < getNumIndirectDests() + 1 &&
            "Successor # out of range for callbr!");
     return i == 0 ? setDefaultDest(NewSucc) : setIndirectDest(i - 1, NewSucc);
   }
 
   unsigned getNumSuccessors() const { return getNumIndirectDests() + 1; }
 
-  BlockAddress *getBlockAddressForIndirectDest(unsigned DestNo) const;
-
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return (I->getOpcode() == Instruction::CallBr);
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 

llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

void SelectionDAGBuilder::visitCallBr(const CallBrInst &I) {
 
   // Update successor info.
   addSuccessorWithProb(CallBrMBB, Return, BranchProbability::getOne());
   for (unsigned i = 0, e = I.getNumIndirectDests(); i < e; ++i) {
     BasicBlock *Dest = I.getIndirectDest(i);
     MachineBasicBlock *Target = FuncInfo.MBBMap[Dest];
     Target->setIsInlineAsmBrIndirectTarget();
     Target->setMachineBlockAddressTaken();
+    Target->setLabelMustBeEmitted();
     // Don't add duplicate machine successors.
     if (Dests.insert(Dest).second)
       addSuccessorWithProb(CallBrMBB, Target, BranchProbability::getZero());
   }
   CallBrMBB->normalizeSuccProbs();
 
   // Drop into default successor.
   DAG.setRoot(DAG.getNode(ISD::BR, getCurSDLoc(),

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

case InlineAsm::isOutput:
         OpInfo.ConstraintVT =
             getAsmOperandValueType(DL, Call.getType()).getSimpleVT();
       }
       ++ResNo;
       break;
     case InlineAsm::isInput:
       OpInfo.CallOperandVal = Call.getArgOperand(ArgNo);
       break;
     case InlineAsm::isLabel:
-      OpInfo.CallOperandVal =
-          cast<CallBrInst>(&Call)->getBlockAddressForIndirectDest(LabelNo);
-      OpInfo.ConstraintVT =
-          getAsmOperandValueType(DL, OpInfo.CallOperandVal->getType())
-              .getSimpleVT();
+      OpInfo.CallOperandVal = cast<CallBrInst>(&Call)->getIndirectDest(LabelNo);
       ++LabelNo;
       continue;
     case InlineAsm::isClobber:
       // Nothing to do.
       break;
     }
 
     if (OpInfo.CallOperandVal) {
       llvm::Type *OpTy = OpInfo.CallOperandVal->getType();
       if (OpInfo.isIndirect) {

llvm/lib/IR/Instructions.cpp

#endif
 
   auto It = populateBundleOperandInfos(Bundles, Args.size());
   (void)It;
   assert(It + 2 + IndirectDests.size() == op_end() && "Should add up!");
 
   setName(NameStr);
 }
 
-BlockAddress *
-CallBrInst::getBlockAddressForIndirectDest(unsigned DestNo) const {
-  return BlockAddress::get(const_cast<Function *>(getFunction()),
-                           getIndirectDest(DestNo));
-}
-
 CallBrInst::CallBrInst(const CallBrInst &CBI)
     : CallBase(CBI.Attrs, CBI.FTy, CBI.getType(), Instruction::CallBr,
                OperandTraits<CallBase>::op_end(this) - CBI.getNumOperands(),
                CBI.getNumOperands()) {
   setCallingConv(CBI.getCallingConv());
   std::copy(CBI.op_begin(), CBI.op_end(), op_begin());
   std::copy(CBI.bundle_op_info_begin(), CBI.bundle_op_info_end(),
             bundle_op_info_begin());

llvm/lib/Target/X86/X86ISelLowering.cpp

       int64_t ExtVal = ExtOpc == ISD::ZERO_EXTEND ? CST->getZExtValue()
                                                   : CST->getSExtValue();
       Result = DAG.getTargetConstant(ExtVal, SDLoc(Op), MVT::i64);
       break;
     }
 
     // In any sort of PIC mode addresses need to be computed at runtime by
     // adding in a register or some sort of table lookup.  These can't
-    // be used as immediates. BlockAddresses are fine though.
+    // be used as immediates. BlockAddresses and BasicBlocks are fine though.
     if ((Subtarget.isPICStyleGOT() || Subtarget.isPICStyleStubPIC()) &&
-        !isa<BlockAddressSDNode>(Op))
+        !(isa<BlockAddressSDNode>(Op) || isa<BasicBlockSDNode>(Op)))
       return;
 
     // If we are in non-pic codegen mode, we allow the address of a global (with
     // an optional displacement) to be used with 'i'.
     if (auto *GA = dyn_cast<GlobalAddressSDNode>(Op))
       // If we require an extra load to get this address, as in PIC mode, we
       // can't accept it.
       if (isGlobalStubReference(

llvm/test/CodeGen/AArch64/callbr-asm-label.ll

 ; RUN: llc < %s -mtriple=aarch64-linux-gnu | FileCheck %s
 
 @X = common local_unnamed_addr global i32 0, align 4
 
 define i32 @test1() {
 ; CHECK-LABEL: test1:
 ; CHECK:         .word b
-; CHECK-NEXT:    .word .Ltmp0
+; CHECK-NEXT:    .word .LBB0_2
 ; CHECK: // %bb.1:
-; CHECK: .Ltmp0:
-; CHECK: .LBB0_2: // %indirect
+; CHECK: .LBB0_2: // Block address taken
 entry:
   callbr void asm sideeffect "1:\0A\09.word b, ${0:l}\0A\09", "!i"()
           to label %cleanup [label %indirect]
 
 indirect:
   br label %cleanup
 
 cleanup:
   %retval.0 = phi i32 [ 1, %indirect ], [ 0, %entry ]
   ret i32 %retval.0
 }
 
 define void @test2() {
 ; CHECK-LABEL: test2:
 entry:
   %0 = load i32, i32* @X, align 4
   %and = and i32 %0, 1
   %tobool = icmp eq i32 %and, 0
   br i1 %tobool, label %if.end10, label %if.then
 
 if.then:
 ; CHECK:       .word b
-; CHECK-NEXT:  .word .Ltmp2
-; CHECK:       .Ltmp2:
-; CHECK-NEXT:  .LBB1_3: // %if.end6
+; CHECK-NEXT:  .word .LBB1_3
+; CHECK:       .LBB1_3: // Block address taken
   callbr void asm sideeffect "1:\0A\09.word b, ${0:l}\0A\09", "!i"()
           to label %if.then4 [label %if.end6]
 
 if.then4:
   %call5 = tail call i32 bitcast (i32 (...)* @g to i32 ()*)()
   br label %if.end6
 
 if.end6:
   %.pre = load i32, i32* @X, align 4
   %.pre13 = and i32 %.pre, 1
   %phitmp = icmp eq i32 %.pre13, 0
   br i1 %phitmp, label %if.end10, label %if.then9
 
 if.then9:
-; CHECK: .Ltmp4:
-; CHECK-NEXT:  .LBB1_5: // %l_yes
+; CHECK: .LBB1_5: // Block address taken
   callbr void asm sideeffect "", "!i"()
           to label %if.end10 [label %l_yes]
 
 if.end10:
   br label %l_yes
 
 l_yes:
   ret void
 }
 
 declare i32 @g(...)

llvm/test/CodeGen/PowerPC/ppc64-inlineasm-clobber.ll

 ; PPC64LE-NEXT:    nop
 ; PPC64LE-NEXT:    #NO_APP
 ; PPC64LE-NEXT:  .LBB3_1: # %return
 ; PPC64LE-NEXT:    extsw r3, r3
 ; PPC64LE-NEXT:    addi r1, r1, 32
 ; PPC64LE-NEXT:    ld r0, 16(r1)
 ; PPC64LE-NEXT:    mtlr r0
 ; PPC64LE-NEXT:    blr
-; PPC64LE-NEXT:  .Ltmp0: # Block address taken
-; PPC64LE-NEXT:  .LBB3_2: # %return_early
+; PPC64LE-NEXT:  .LBB3_2: # Block address taken
+; PPC64LE-NEXT:    # %return_early
+; PPC64LE-NEXT:    # Label of block must be emitted
 ; PPC64LE-NEXT:    li r3, 0
 ; PPC64LE-NEXT:    b .LBB3_1
 ;
 ; PPC64BE-LABEL: ClobberLR_BR:
 ; PPC64BE:       # %bb.0: # %entry
 ; PPC64BE-NEXT:    mflr r0
 ; PPC64BE-NEXT:    std r0, 16(r1)
 ; PPC64BE-NEXT:    stdu r1, -48(r1)
 ; PPC64BE-NEXT:    #APP
 ; PPC64BE-NEXT:    nop
 ; PPC64BE-NEXT:    #NO_APP
 ; PPC64BE-NEXT:  .LBB3_1: # %return
 ; PPC64BE-NEXT:    extsw r3, r3
 ; PPC64BE-NEXT:    addi r1, r1, 48
 ; PPC64BE-NEXT:    ld r0, 16(r1)
 ; PPC64BE-NEXT:    mtlr r0
 ; PPC64BE-NEXT:    blr
-; PPC64BE-NEXT:  .Ltmp0: # Block address taken
-; PPC64BE-NEXT:  .LBB3_2: # %return_early
+; PPC64BE-NEXT:  .LBB3_2: # Block address taken
+; PPC64BE-NEXT:    # %return_early
+; PPC64BE-NEXT:    # Label of block must be emitted
 ; PPC64BE-NEXT:    li r3, 0
 ; PPC64BE-NEXT:    b .LBB3_1
 entry:
   callbr void asm sideeffect "nop", "!i,~{lr}"()
           to label %return [label %return_early]
 
 return_early:
   br label %return
 
 return:
   %retval.0 = phi i32 [ 0, %return_early ], [ %in, %entry ]
   ret i32 %retval.0
 }
 
 define dso_local signext i32 @ClobberR5_BR(i32 signext %in) #0 {
 ; PPC64LE-LABEL: ClobberR5_BR:
 ; PPC64LE:       # %bb.0: # %entry
 ; PPC64LE-NEXT:    #APP
 ; PPC64LE-NEXT:    nop
 ; PPC64LE-NEXT:    #NO_APP
 ; PPC64LE-NEXT:  # %bb.1: # %return
 ; PPC64LE-NEXT:    extsw r3, r3
 ; PPC64LE-NEXT:    blr
-; PPC64LE-NEXT:  .Ltmp1: # Block address taken
-; PPC64LE-NEXT:  .LBB4_2: # %return_early
+; PPC64LE-NEXT:  .LBB4_2: # Block address taken
+; PPC64LE-NEXT:    # %return_early
+; PPC64LE-NEXT:    # Label of block must be emitted
 ; PPC64LE-NEXT:    li r3, 0
 ; PPC64LE-NEXT:    extsw r3, r3
 ; PPC64LE-NEXT:    blr
 ;
 ; PPC64BE-LABEL: ClobberR5_BR:
 ; PPC64BE:       # %bb.0: # %entry
 ; PPC64BE-NEXT:    #APP
 ; PPC64BE-NEXT:    nop
 ; PPC64BE-NEXT:    #NO_APP
 ; PPC64BE-NEXT:  # %bb.1: # %return
 ; PPC64BE-NEXT:    extsw r3, r3
 ; PPC64BE-NEXT:    blr
-; PPC64BE-NEXT:  .Ltmp1: # Block address taken
-; PPC64BE-NEXT:  .LBB4_2: # %return_early
+; PPC64BE-NEXT:  .LBB4_2: # Block address taken
+; PPC64BE-NEXT:    # %return_early
+; PPC64BE-NEXT:    # Label of block must be emitted
 ; PPC64BE-NEXT:    li r3, 0
 ; PPC64BE-NEXT:    extsw r3, r3
 ; PPC64BE-NEXT:    blr
 entry:
   callbr void asm sideeffect "nop", "!i,~{r5}"()
           to label %return [label %return_early]
 
 return_early:

llvm/test/CodeGen/X86/callbr-asm-bb-exports.ll

 ; REQUIRES: asserts
 ; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -o /dev/null -debug-only=isel 2>&1 | FileCheck %s
 
 ; Make sure we emit the basic block exports and the TokenFactor before the
 ; inlineasm_br. Not sure how to get a MachineIR change so this reads the debug
 ; output from SelectionDAG.
 
 ; CHECK: t0: ch = EntryToken
-; CHECK-NEXT: t16: i64 = BlockAddress<@test, %fail> 0
 ; CHECK-NEXT: t4: i32,ch = CopyFromReg t0, Register:i32 %3
 ; CHECK-NEXT: t10: i32 = add t4, Constant:i32<1>
 ; CHECK-NEXT: t12: ch = CopyToReg t0, Register:i32 %0, t10
 ; CHECK-NEXT: t6: i32,ch = CopyFromReg t0, Register:i32 %4
 ; CHECK-NEXT: t13: i32 = add t6, Constant:i32<1>
 ; CHECK-NEXT: t15: ch = CopyToReg t0, Register:i32 %1, t13
 ; CHECK-NEXT: t17: ch = TokenFactor t12, t15
 ; CHECK-NEXT: t2: i32,ch = CopyFromReg t0, Register:i32 %2
 ; CHECK-NEXT: t8: i32 = add t2, Constant:i32<4>
 ; CHECK-NEXT: t22: ch,glue = CopyToReg t17, Register:i32 %5, t8
-; CHECK-NEXT: t30: ch,glue = inlineasm_br t22, TargetExternalSymbol:i64'xorl $0, $0; jmp ${1:l}', MDNode:ch<null>, TargetConstant:i64<0>, TargetConstant:i32<2359305>, Register:i32 %5, TargetConstant:i64<13>, TargetBlockAddress:i64<@test, %fail> 0, TargetConstant:i32<12>, Register:i32 $df, TargetConstant:i32<12>, Register:i16 $fpsw, TargetConstant:i32<12>, Register:i32 $eflags, t22:1
+; CHECK-NEXT: t29: ch,glue = inlineasm_br t22, TargetExternalSymbol:i64'xorl $0, $0; jmp ${1:l}', MDNode:ch<null>, TargetConstant:i64<0>, TargetConstant:i32<2359305>, Register:i32 %5, TargetConstant:i64<13>, BasicBlock:ch<fail 0x{{[0-9a-f]+}}>, TargetConstant:i32<12>, Register:i32 $df, TargetConstant:i32<12>, Register:i16 $fpsw, TargetConstant:i32<12>, Register:i32 $eflags, t22:1
 
 define i32 @test(i32 %a, i32 %b, i32 %c) {
 entry:
   %0 = add i32 %a, 4
   %1 = add i32 %b, 1
   %2 = add i32 %c, 1
   callbr void asm "xorl $0, $0; jmp ${1:l}", "r,!i,~{dirflag},~{fpsr},~{flags}"(i32 %0) to label %normal [label %fail]
 
 normal:
   ret i32 %1
 
 fail:
   ret i32 %2
 }

llvm/test/CodeGen/X86/callbr-asm-blockplacement.ll

 ; CHECK-NEXT:  # %bb.3: # %bb15
 ; CHECK-NEXT:    leaq (%rbp,%rbp,2), %rax
 ; CHECK-NEXT:    movq %rbx, global+16(,%rax,8)
 ; CHECK-NEXT:    movabsq $-2305847407260205056, %rbx # imm = 0xDFFFFC0000000000
 ; CHECK-NEXT:    #APP
 ; CHECK-NEXT:    #NO_APP
 ; CHECK-NEXT:  # %bb.4: # %bb17
 ; CHECK-NEXT:    callq widget@PLT
-; CHECK-NEXT:  .Ltmp0: # Block address taken
-; CHECK-NEXT:  .LBB0_5: # %bb18
+; CHECK-NEXT:  .LBB0_5: # Block address taken
+; CHECK-NEXT:    # %bb18
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    movw $0, 14(%rbx)
 ; CHECK-NEXT:    addq $8, %rsp
 ; CHECK-NEXT:    popq %rbx
 ; CHECK-NEXT:    popq %r12
 ; CHECK-NEXT:    popq %r13
 ; CHECK-NEXT:    popq %r14
 ; CHECK-NEXT:    popq %r15
 ; CHECK-NEXT:    popq %rbp

llvm/test/CodeGen/X86/callbr-asm-branch-folding.ll

 ; CHECK-NEXT:  # %bb.5: # %if.end12
 ; CHECK-NEXT:    testl %ebp, %ebp
 ; CHECK-NEXT:    je .LBB0_8
 ; CHECK-NEXT:  # %bb.6: # %if.then14
 ; CHECK-NEXT:    movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload
 ; CHECK-NEXT:    #APP
 ; CHECK-NEXT:    #NO_APP
 ; CHECK-NEXT:    jmp .LBB0_9
-; CHECK-NEXT:  .Ltmp0: # Block address taken
-; CHECK-NEXT:  # %bb.7: # %if.then20.critedge
+; CHECK-NEXT:  .LBB0_7: # Block address taken
+; CHECK-NEXT:    # %if.then20.critedge
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    movl j(%rip), %edi
 ; CHECK-NEXT:    movslq %eax, %rcx
 ; CHECK-NEXT:    movl $1, %esi
 ; CHECK-NEXT:    movq %r15, %rdx
 ; CHECK-NEXT:    addq $8, %rsp
 ; CHECK-NEXT:    popq %rbx
 ; CHECK-NEXT:    popq %r12
 ; CHECK-NEXT:    popq %r13

llvm/test/CodeGen/X86/callbr-asm-destinations.ll

 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
 ; RUN: llc -mtriple=i686-- -verify-machineinstrs < %s | FileCheck %s
 
 define i32 @duplicate_normal_and_indirect_dest(i32 %a) {
 ; CHECK-LABEL: duplicate_normal_and_indirect_dest:
 ; CHECK:       # %bb.0: # %entry
 ; CHECK-NEXT:    movl {{[0-9]+}}(%esp), %eax
 ; CHECK-NEXT:    addl $4, %eax
 ; CHECK-NEXT:    #APP
 ; CHECK-NEXT:    xorl %eax, %eax
-; CHECK-NEXT:    jmp .Ltmp0
+; CHECK-NEXT:    jmp .LBB0_1
 ; CHECK-NEXT:    #NO_APP
-; CHECK-NEXT:  .Ltmp0: # Block address taken
-; CHECK-NEXT:  # %bb.1: # %fail
+; CHECK-NEXT:  .LBB0_1: # Block address taken
+; CHECK-NEXT:    # %fail
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    movl $1, %eax
 ; CHECK-NEXT:    retl
 entry:
   %0 = add i32 %a, 4
   callbr void asm "xorl $0, $0; jmp ${1:l}", "r,!i,~{dirflag},~{fpsr},~{flags}"(i32 %0) to label %fail [label %fail]
 
 fail:
   ret i32 1
 }
 
 define i32 @duplicate_indirect_dest(i32 %a) {
 ; CHECK-LABEL: duplicate_indirect_dest:
 ; CHECK:       # %bb.0: # %entry
 ; CHECK-NEXT:    movl {{[0-9]+}}(%esp), %eax
 ; CHECK-NEXT:    addl $4, %eax
 ; CHECK-NEXT:    #APP
 ; CHECK-NEXT:    xorl %eax, %eax
-; CHECK-NEXT:    jmp .Ltmp1
-; CHECK-NEXT:    jmp .Ltmp1
+; CHECK-NEXT:    jmp .LBB1_2
+; CHECK-NEXT:    jmp .LBB1_2
 ; CHECK-NEXT:    #NO_APP
 ; CHECK-NEXT:  # %bb.1: # %normal
 ; CHECK-NEXT:    retl
-; CHECK-NEXT:  .Ltmp1: # Block address taken
-; CHECK-NEXT:  .LBB1_2: # %fail
+; CHECK-NEXT:  .LBB1_2: # Block address taken
+; CHECK-NEXT:    # %fail
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    movl $1, %eax
 ; CHECK-NEXT:    retl
 entry:
   %0 = add i32 %a, 4
   callbr void asm "xorl $0, $0; jmp ${1:l}; jmp ${2:l}", "r,!i,!i,~{dirflag},~{fpsr},~{flags}"(i32 %0) to label %normal [label %fail, label %fail]
 
 normal:
   ret i32 %0
 
 fail:
   ret i32 1
 }

llvm/test/CodeGen/X86/callbr-asm-instr-scheduling.ll

 ; CHECK-NEXT:    andq %rax, %rdx
 ; CHECK-NEXT:    movzbl pgdir_shift(%rip), %eax
 ; CHECK-NEXT:    movq page_offset_base(%rip), %rcx
 ; CHECK-NEXT:    shrxq %rax, %rdi, %rax
 ; CHECK-NEXT:    addq %rcx, %rdx
 ; CHECK-NEXT:    andl $511, %eax # imm = 0x1FF
 ; CHECK-NEXT:    leaq (%rdx,%rax,8), %rax
 ; CHECK-NEXT:    #APP
+; CHECK-NEXT:  .Ltmp0:
+; CHECK-NEXT:    jmp .Ltmp1
 ; CHECK-NEXT:  .Ltmp2:
-; CHECK-NEXT:    jmp .Ltmp3
-; CHECK-NEXT:  .Ltmp4:
-; CHECK-NEXT:    .zero (-(((.Ltmp5-.Ltmp6)-(.Ltmp4-.Ltmp2))>0))*((.Ltmp5-.Ltmp6)-(.Ltmp4-.Ltmp2)),144
-; CHECK-NEXT:  .Ltmp7:
+; CHECK-NEXT:    .zero (-(((.Ltmp3-.Ltmp4)-(.Ltmp2-.Ltmp0))>0))*((.Ltmp3-.Ltmp4)-(.Ltmp2-.Ltmp0)),144
+; CHECK-NEXT:  .Ltmp5:
 entry:
   %0 = tail call i64 asm sideeffect "mov %cr3,$0\0A\09", "=r,=*m,~{dirflag},~{fpsr},~{flags}"(ptr elementtype(i64) nonnull @__force_order)
   %and.i = and i64 %0, 9223372036854771712
   %1 = load i64, ptr @page_offset_base, align 8
   %add = add i64 %and.i, %1
   %2 = inttoptr i64 %add to ptr
   %3 = load i32, ptr @pgdir_shift, align 4
   %sh_prom = zext i32 %3 to i64

llvm/test/CodeGen/X86/callbr-asm-label-addr.ll

 ; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu | FileCheck %s
 
 define i32 @test1(i32 %x) {
 ; CHECK-LABEL: test1:
 ; CHECK:         .quad .Ltmp0
-; CHECK-NEXT:    .quad .Ltmp1
-; CHECK: .Ltmp1:
-; CHECK-NEXT: # %bb.1: # %bar
+; CHECK-NEXT:    .quad .LBB0_1
+; CHECK:         .LBB0_1: # Block address taken
+; CHECK-NEXT:    # %bar
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    callq foo
 ; CHECK-NEXT: .Ltmp0:
 ; CHECK-NEXT:  # %bb.2: # %baz
 entry:
   callbr void asm sideeffect ".quad ${0:l}\0A\09.quad ${1:l}", "i,!i,~{dirflag},~{fpsr},~{flags}"(ptr blockaddress(@test1, %baz))
           to label %asm.fallthrough [label %bar]
 
 asm.fallthrough:

llvm/test/CodeGen/X86/callbr-asm-outputs-pred-succ.ll

 ; The fallthrough is a block containing a second INLINEASM_BR. Check it has two successors,
 ; and the the probability for fallthrough is 100%.
 ; CHECK: bb.1 (%ir-block.4):
 ; CHECK-NEXT: predecessors: %bb.0
 ; CHECK-NEXT: successors: %bb.3(0x80000000), %bb.2(0x00000000); %bb.3(100.00%), %bb.2(0.00%)
 
 ; Check the second INLINEASM_BR target block is preceded by the block with the
 ; second INLINEASM_BR.
-; CHECK: bb.2 (%ir-block.7, machine-block-address-taken, ir-block-address-taken %ir-block.7, inlineasm-br-indirect-target):
+; CHECK: bb.2 (%ir-block.7, machine-block-address-taken, inlineasm-br-indirect-target):
 ; CHECK-NEXT: predecessors: %bb.1
 
 ; Check the first INLINEASM_BR target block is predecessed by the block with
 ; the first INLINEASM_BR.
-; CHECK: bb.4 (%ir-block.11, machine-block-address-taken, ir-block-address-taken %ir-block.11, inlineasm-br-indirect-target):
+; CHECK: bb.4 (%ir-block.11, machine-block-address-taken, inlineasm-br-indirect-target):
 ; CHECK-NEXT: predecessors: %bb.0
 
 @.str = private unnamed_addr constant [26 x i8] c"inline asm#1 returned %d\0A\00", align 1
 @.str.2 = private unnamed_addr constant [26 x i8] c"inline asm#2 returned %d\0A\00", align 1
 @str = private unnamed_addr constant [30 x i8] c"inline asm#1 caused exception\00", align 1
 @str.4 = private unnamed_addr constant [30 x i8] c"inline asm#2 caused exception\00", align 1
 
 ; Function Attrs: nounwind uwtable

llvm/test/CodeGen/X86/callbr-asm-outputs.ll

 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
 ; RUN: llc -mtriple=i686-- -verify-machineinstrs < %s | FileCheck %s
 
 ; A test for asm-goto output
 
 define i32 @test1(i32 %x) {
 ; CHECK-LABEL: test1:
 ; CHECK:       # %bb.0: # %entry
 ; CHECK-NEXT:    movl {{[0-9]+}}(%esp), %eax
 ; CHECK-NEXT:    addl $4, %eax
 ; CHECK-NEXT:    #APP
 ; CHECK-NEXT:    xorl %eax, %eax
-; CHECK-NEXT:    jmp .Ltmp0
+; CHECK-NEXT:    jmp .LBB0_2
 ; CHECK-NEXT:    #NO_APP
 ; CHECK-NEXT:  # %bb.1: # %normal
 ; CHECK-NEXT:    retl
-; CHECK-NEXT:  .Ltmp0: # Block address taken
-; CHECK-NEXT:  .LBB0_2: # %abnormal
+; CHECK-NEXT:  .LBB0_2: # Block address taken
+; CHECK-NEXT:    # %abnormal
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    movl $1, %eax
 ; CHECK-NEXT:    retl
 entry:
   %add = add nsw i32 %x, 4
   %ret = callbr i32 asm "xorl $1, $0; jmp ${2:l}", "=r,r,!i,~{dirflag},~{fpsr},~{flags}"(i32 %add)
           to label %normal [label %abnormal]
 
 normal:

 ; CHECK-NEXT:    movl {{[0-9]+}}(%esp), %esi
 ; CHECK-NEXT:    movl $-1, %eax
 ; CHECK-NEXT:    cmpl %edi, %esi
 ; CHECK-NEXT:    jge .LBB1_2
 ; CHECK-NEXT:  # %bb.1: # %if.then
 ; CHECK-NEXT:    #APP
 ; CHECK-NEXT:    testl %esi, %esi
 ; CHECK-NEXT:    testl %edi, %esi
-; CHECK-NEXT:    jne .Ltmp1
+; CHECK-NEXT:    jne .LBB1_4
 ; CHECK-NEXT:    #NO_APP
 ; CHECK-NEXT:    jmp .LBB1_3
 ; CHECK-NEXT:  .LBB1_2: # %if.else
 ; CHECK-NEXT:    #APP
 ; CHECK-NEXT:    testl %esi, %edi
 ; CHECK-NEXT:    testl %esi, %edi
-; CHECK-NEXT:    jne .Ltmp2
+; CHECK-NEXT:    jne .LBB1_5
 ; CHECK-NEXT:    #NO_APP
 ; CHECK-NEXT:  .LBB1_3:
 ; CHECK-NEXT:    movl %esi, %eax
 ; CHECK-NEXT:    addl %edi, %eax
-; CHECK-NEXT:  .Ltmp2: # Block address taken
-; CHECK-NEXT:  .LBB1_5: # %return
+; CHECK-NEXT:  .LBB1_5: # Block address taken
+; CHECK-NEXT:    # %return
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    popl %esi
 ; CHECK-NEXT:    .cfi_def_cfa_offset 8
 ; CHECK-NEXT:    popl %edi
 ; CHECK-NEXT:    .cfi_def_cfa_offset 4
 ; CHECK-NEXT:    retl
-; CHECK-NEXT:  .Ltmp1: # Block address taken
-; CHECK-NEXT:  .LBB1_4: # %label_true
+; CHECK-NEXT:  .LBB1_4: # Block address taken
+; CHECK-NEXT:    # %label_true
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    .cfi_def_cfa_offset 12
 ; CHECK-NEXT:    movl $-2, %eax
 ; CHECK-NEXT:    jmp .LBB1_5
 entry:
   %cmp = icmp slt i32 %out1, %out2
   br i1 %cmp, label %if.then, label %if.else
 
 if.then:                                          ; preds = %entry

 ; CHECK-NEXT:  # %bb.4:
 ; CHECK-NEXT:    movl %edx, %eax
 ; CHECK-NEXT:  .LBB2_5: # %asm.fallthrough
 ; CHECK-NEXT:    popl %esi
 ; CHECK-NEXT:    .cfi_def_cfa_offset 8
 ; CHECK-NEXT:    popl %edi
 ; CHECK-NEXT:    .cfi_def_cfa_offset 4
 ; CHECK-NEXT:    retl
-; CHECK-NEXT:  .Ltmp3: # Block address taken
-; CHECK-NEXT:  .LBB2_6: # %indirect
+; CHECK-NEXT:  .LBB2_6: # Block address taken
+; CHECK-NEXT:    # %indirect
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    .cfi_def_cfa_offset 12
 ; CHECK-NEXT:    movl $42, %eax
 ; CHECK-NEXT:    jmp .LBB2_5
 entry:
   br i1 %cmp, label %true, label %false
 
 true:
   %0 = callbr { i32, i32 } asm sideeffect ".word $0, $1", "={si},={di},!i" () to label %asm.fallthrough [label %indirect]

 define i32 @test4(i32 %out1, i32 %out2) {
 ; CHECK-LABEL: test4:
 ; CHECK:       # %bb.0: # %entry
 ; CHECK-NEXT:    movl $-1, %eax
 ; CHECK-NEXT:    movl {{[0-9]+}}(%esp), %ecx
 ; CHECK-NEXT:    #APP
 ; CHECK-NEXT:    testl %ecx, %ecx
 ; CHECK-NEXT:    testl %edx, %ecx
-; CHECK-NEXT:    jne .Ltmp4
+; CHECK-NEXT:    jne .LBB3_3
 ; CHECK-NEXT:    #NO_APP
 ; CHECK-NEXT:  # %bb.1: # %asm.fallthrough
 ; CHECK-NEXT:    #APP
 ; CHECK-NEXT:    testl %ecx, %edx
 ; CHECK-NEXT:    testl %ecx, %edx
-; CHECK-NEXT:    jne .Ltmp5
+; CHECK-NEXT:    jne .LBB3_4
 ; CHECK-NEXT:    #NO_APP
 ; CHECK-NEXT:  # %bb.2: # %asm.fallthrough2
 ; CHECK-NEXT:    addl %edx, %ecx
 ; CHECK-NEXT:    movl %ecx, %eax
 ; CHECK-NEXT:    retl
-; CHECK-NEXT:  .Ltmp4: # Block address taken
-; CHECK-NEXT:  .LBB3_3: # %label_true
+; CHECK-NEXT:  .LBB3_3: # Block address taken
+; CHECK-NEXT:    # %label_true
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    movl $-2, %eax
-; CHECK-NEXT:  .Ltmp5: # Block address taken
-; CHECK-NEXT:  .LBB3_4: # %return
+; CHECK-NEXT:  .LBB3_4: # Block address taken
+; CHECK-NEXT:    # %return
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    retl
 entry:
   %0 = callbr { i32, i32 } asm sideeffect "testl $0, $0; testl $1, $2; jne ${3:l}", "=r,=r,r,!i,!i,~{dirflag},~{fpsr},~{flags}"(i32 %out1)
           to label %asm.fallthrough [label %label_true, label %return]
 
 asm.fallthrough:                                  ; preds = %entry
   %asmresult = extractvalue { i32, i32 } %0, 0
   %asmresult1 = extractvalue { i32, i32 } %0, 1

 ; GCCAsmStmt being turned into "={esp},0" since after D87279 they're turned
 ; into "={esp},{esp}". This previously caused an ICE; this test is more so
 ; about avoiding another ICE than what the actual output is.
 define dso_local void @test5() {
 ; CHECK-LABEL: test5:
 ; CHECK:       # %bb.0:
 ; CHECK-NEXT:    #APP
 ; CHECK-NEXT:    #NO_APP
-; CHECK-NEXT:  .Ltmp6: # Block address taken
-; CHECK-NEXT:  # %bb.1:
+; CHECK-NEXT:  .LBB4_1: # Block address taken
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    retl
   %1 = call i32 @llvm.read_register.i32(metadata !3)
   %2 = callbr i32 asm "", "={esp},!i,{esp},~{dirflag},~{fpsr},~{flags}"(i32 %1)
           to label %3 [label %4]
 
 3:
   call void @llvm.write_register.i32(metadata !3, i32 %2)
   br label %4
 
 4:
   ret void
 }
 
 declare i32 @llvm.read_register.i32(metadata)
 declare void @llvm.write_register.i32(metadata, i32)
 !3 = !{!"esp"}

llvm/test/CodeGen/X86/callbr-asm-phi-placement.ll

 
 define void @test1(ptr %arg, ptr %mem) nounwind {
 ; CHECK-LABEL: test1:
 ; CHECK:       # %bb.0: # %entry
 ; CHECK-NEXT:    pushq %r14
 ; CHECK-NEXT:    pushq %rbx
 ; CHECK-NEXT:    pushq %rax
 ; CHECK-NEXT:    movq %rsi, %r14
-; CHECK-NEXT:  .Ltmp0: # Block address taken
-; CHECK-NEXT:  .LBB0_1: # %loop
+; CHECK-NEXT:  .LBB0_1: # Block address taken
+; CHECK-NEXT:    # %loop
 ; CHECK-NEXT:    # =>This Inner Loop Header: Depth=1
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    movq (%r14), %rbx
 ; CHECK-NEXT:    callq foo@PLT
 ; CHECK-NEXT:    movq %rbx, %rdi
 ; CHECK-NEXT:    #APP
 ; CHECK-NEXT:    #NO_APP
 ; CHECK-NEXT:  # %bb.2: # %end
 ; CHECK-NEXT:    addq $8, %rsp
 ; CHECK-NEXT:    popq %rbx

llvm/test/CodeGen/X86/callbr-asm-sink.ll

 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
 ; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu | FileCheck %s
 
 ;; Verify that the machine instructions generated from the first
 ;; getelementptr don't get sunk below the callbr. (Reduced from a bug
 ;; report.)
 
 %struct1 = type { i8*, i32 }
 
 define void @klist_dec_and_del(%struct1*) {
 ; CHECK-LABEL: klist_dec_and_del:
 ; CHECK:       # %bb.0:
 ; CHECK-NEXT:    leaq 8(%rdi), %rax
 ; CHECK-NEXT:    #APP
-; CHECK-NEXT:    # 8(%rdi) .Ltmp0
+; CHECK-NEXT:    # 8(%rdi) .LBB0_1
 ; CHECK-NEXT:    #NO_APP
 ; CHECK-NEXT:  # %bb.2:
 ; CHECK-NEXT:    retq
-; CHECK-NEXT:  .Ltmp0: # Block address taken
-; CHECK-NEXT:  .LBB0_1:
+; CHECK-NEXT:  .LBB0_1: # Block address taken
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    movq $0, -8(%rax)
 ; CHECK-NEXT:    retq
   %2 = getelementptr inbounds %struct1, %struct1* %0, i64 0, i32 1
   callbr void asm sideeffect "# $0 $1", "*m,!i,~{memory},~{dirflag},~{fpsr},~{flags}"(i32* elementtype(i32) %2)
           to label %6 [label %3]
 
 3:
   %4 = getelementptr i32, i32* %2, i64 -2
   %5 = bitcast i32* %4 to i8**
   store i8* null, i8** %5, align 8
   br label %6
 
 6:
   ret void
 }

llvm/test/CodeGen/X86/callbr-asm.ll

 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
 ; RUN: llc < %s -mtriple=i686-- -O3 -verify-machineinstrs | FileCheck %s
 
 ; Tests for using callbr as an asm-goto wrapper
 
 ; Test 1 - fallthrough label gets removed, but the fallthrough code that is
 ; unreachable due to asm ending on a jmp is still left in.
 define i32 @test1(i32 %a) {
 ; CHECK-LABEL: test1:
 ; CHECK:       # %bb.0: # %entry
 ; CHECK-NEXT:    movl {{[0-9]+}}(%esp), %eax
 ; CHECK-NEXT:    addl $4, %eax
 ; CHECK-NEXT:    #APP
 ; CHECK-NEXT:    xorl %eax, %eax
-; CHECK-NEXT:    jmp .Ltmp0
+; CHECK-NEXT:    jmp .LBB0_2
 ; CHECK-NEXT:    #NO_APP
 ; CHECK-NEXT:  # %bb.1: # %normal
 ; CHECK-NEXT:    xorl %eax, %eax
 ; CHECK-NEXT:    retl
-; CHECK-NEXT:  .Ltmp0: # Block address taken
-; CHECK-NEXT:  .LBB0_2: # %fail
+; CHECK-NEXT:  .LBB0_2: # Block address taken
+; CHECK-NEXT:    # %fail
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    movl $1, %eax
 ; CHECK-NEXT:    retl
 entry:
   %0 = add i32 %a, 4
   callbr void asm "xorl $0, $0; jmp ${1:l}", "r,!i,~{dirflag},~{fpsr},~{flags}"(i32 %0) to label %normal [label %fail]
 
 normal:
   ret i32 0
 
 fail:
   ret i32 1
 }
 
 ; Test 1b - Like test 1 but using `asm inteldialect`.
 define i32 @test1b(i32 %a) {
 ; CHECK-LABEL: test1b:
 ; CHECK:       # %bb.0: # %entry
 ; CHECK-NEXT:    movl {{[0-9]+}}(%esp), %eax
 ; CHECK-NEXT:    addl $4, %eax
 ; CHECK-NEXT:    #APP
 ; CHECK-EMPTY:
 ; CHECK-NEXT:    xorl %eax, %eax
-; CHECK-NEXT:    jmp .Ltmp1
+; CHECK-NEXT:    jmp .LBB1_2
 ; CHECK-EMPTY:
 ; CHECK-NEXT:    #NO_APP
 ; CHECK-NEXT:  # %bb.1: # %normal
 ; CHECK-NEXT:    xorl %eax, %eax
 ; CHECK-NEXT:    retl
-; CHECK-NEXT:  .Ltmp1: # Block address taken
-; CHECK-NEXT:  .LBB1_2: # %fail
+; CHECK-NEXT:  .LBB1_2: # Block address taken
+; CHECK-NEXT:    # %fail
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    movl $1, %eax
 ; CHECK-NEXT:    retl
 entry:
   %0 = add i32 %a, 4
   callbr void asm inteldialect "xor $0, $0; jmp ${1:l}", "r,!i,~{dirflag},~{fpsr},~{flags}"(i32 %0) to label %normal [label %fail]
 
 normal:
   ret i32 0

 }
 
 ; Test 3 - asm-goto implements a loop. The loop gets recognized, but many loop
 ; transforms fail due to canonicalization having callbr exceptions. Trivial
 ; blocks at labels 1 and 3 also don't get simplified due to callbr.
 define i32 @test3(i32 %a) {
 ; CHECK-LABEL: test3:
 ; CHECK:       # %bb.0: # %entry
-; CHECK-NEXT:  .Ltmp2: # Block address taken
-; CHECK-NEXT:  .LBB3_1: # %label01
+; CHECK-NEXT:  .LBB3_1: # Block address taken
+; CHECK-NEXT:    # %label01
 ; CHECK-NEXT:    # =>This Loop Header: Depth=1
 ; CHECK-NEXT:    # Child Loop BB3_2 Depth 2
 ; CHECK-NEXT:    # Child Loop BB3_3 Depth 3
 ; CHECK-NEXT:    # Child Loop BB3_4 Depth 4
-; CHECK-NEXT:  .Ltmp3: # Block address taken
-; CHECK-NEXT:  .LBB3_2: # %label02
+; CHECK-NEXT:    # Label of block must be emitted
+; CHECK-NEXT:  .LBB3_2: # Block address taken
+; CHECK-NEXT:    # %label02
 ; CHECK-NEXT:    # Parent Loop BB3_1 Depth=1
 ; CHECK-NEXT:    # => This Loop Header: Depth=2
 ; CHECK-NEXT:    # Child Loop BB3_3 Depth 3
 ; CHECK-NEXT:    # Child Loop BB3_4 Depth 4
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    addl $4, {{[0-9]+}}(%esp)
-; CHECK-NEXT:  .Ltmp4: # Block address taken
-; CHECK-NEXT:  .LBB3_3: # %label03
+; CHECK-NEXT:  .LBB3_3: # Block address taken
+; CHECK-NEXT:    # %label03
 ; CHECK-NEXT:    # Parent Loop BB3_1 Depth=1
 ; CHECK-NEXT:    # Parent Loop BB3_2 Depth=2
 ; CHECK-NEXT:    # => This Loop Header: Depth=3
 ; CHECK-NEXT:    # Child Loop BB3_4 Depth 4
-; CHECK-NEXT:  .Ltmp5: # Block address taken
-; CHECK-NEXT:  .LBB3_4: # %label04
+; CHECK-NEXT:    # Label of block must be emitted
+; CHECK-NEXT:  .LBB3_4: # Block address taken
+; CHECK-NEXT:    # %label04
 ; CHECK-NEXT:    # Parent Loop BB3_1 Depth=1
 ; CHECK-NEXT:    # Parent Loop BB3_2 Depth=2
 ; CHECK-NEXT:    # Parent Loop BB3_3 Depth=3
 ; CHECK-NEXT:    # => This Inner Loop Header: Depth=4
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    #APP
-; CHECK-NEXT:    jmp .Ltmp2
-; CHECK-NEXT:    jmp .Ltmp3
-; CHECK-NEXT:    jmp .Ltmp4
+; CHECK-NEXT:    jmp .LBB3_1
+; CHECK-NEXT:    jmp .LBB3_2
+; CHECK-NEXT:    jmp .LBB3_3
 ; CHECK-NEXT:    #NO_APP
 ; CHECK-NEXT:  # %bb.5: # %normal0
 ; CHECK-NEXT:    # in Loop: Header=BB3_4 Depth=4
 ; CHECK-NEXT:    #APP
-; CHECK-NEXT:    jmp .Ltmp2
-; CHECK-NEXT:    jmp .Ltmp3
-; CHECK-NEXT:    jmp .Ltmp4
-; CHECK-NEXT:    jmp .Ltmp5
+; CHECK-NEXT:    jmp .LBB3_1
+; CHECK-NEXT:    jmp .LBB3_2
+; CHECK-NEXT:    jmp .LBB3_3
+; CHECK-NEXT:    jmp .LBB3_4
 ; CHECK-NEXT:    #NO_APP
 ; CHECK-NEXT:  # %bb.6: # %normal1
 ; CHECK-NEXT:    movl {{[0-9]+}}(%esp), %eax
 ; CHECK-NEXT:    retl
 entry:
   %a.addr = alloca i32, align 4
   store i32 %a, ptr %a.addr, align 4
   br label %label01
normal1:                                          ; preds = %normal0
   ret i32 %1
 }
 
 ; Test 4 - asm-goto referenced with the 'l' (ell) modifier and not.
 define void @test4() {
 ; CHECK-LABEL: test4:
 ; CHECK:       # %bb.0: # %entry
 ; CHECK-NEXT:    #APP
-; CHECK-NEXT:    ja .Ltmp6
+; CHECK-NEXT:    ja .LBB4_3
 ; CHECK-NEXT:    #NO_APP
 ; CHECK-NEXT:  # %bb.1: # %asm.fallthrough
 ; CHECK-NEXT:    #APP
-; CHECK-NEXT:    ja .Ltmp6
+; CHECK-NEXT:    ja .LBB4_3
 ; CHECK-NEXT:    #NO_APP
-; CHECK-NEXT:  .Ltmp6: # Block address taken
-; CHECK-NEXT:  .LBB4_3: # %quux
+; CHECK-NEXT:  .LBB4_3: # Block address taken
+; CHECK-NEXT:    # %quux
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    retl
 entry:
   callbr void asm sideeffect "ja $0", "!i,~{dirflag},~{fpsr},~{flags}"()
           to label %asm.fallthrough [label %quux]
 
 asm.fallthrough:                                  ; preds = %entry
   callbr void asm sideeffect "ja ${0:l}", "!i,~{dirflag},~{fpsr},~{flags}"()
           to label %cleanup [label %quux]
 
 quux:                                             ; preds = %asm.fallthrough, %entry
   br label %cleanup
 
 cleanup:                                          ; preds = %asm.fallthrough, %quux
   ret void
 }

llvm/test/CodeGen/X86/inline-asm-pic.ll

 
 ; The intent of this test is to ensure that we handle blockaddress' correctly
 ; with "i" constraints for -m32 -fPIC.
 
 define void @x() {
 ; CHECK-LABEL: x:
 ; CHECK:       ## %bb.0:
 ; CHECK-NEXT:    ## InlineAsm Start
-; CHECK-NEXT:    ## Ltmp0
+; CHECK-NEXT:    ## LBB1_1
 ; CHECK-EMPTY:
 ; CHECK-NEXT:    ## InlineAsm End
 ; CHECK-NEXT:  ## %bb.2: ## %return
 ; CHECK-NEXT:    retl
 ; CHECK-NEXT:  Ltmp0: ## Block address taken
 ; CHECK-NEXT:  LBB1_1: ## %overflow
+; CHECK-NEXT:    ## Label of block must be emitted
 ; CHECK-NEXT:    retl
   callbr void asm "#  ${0:l}\0A", "!i"()
           to label %return [label %overflow]
 
 overflow:
   br label %return
 
 return:

llvm/test/CodeGen/X86/shrinkwrap-callbr.ll

 ; CHECK:       # %bb.0: # %entry
 ; CHECK-NEXT:    pushq %rax
 ; CHECK-NEXT:    .cfi_def_cfa_offset 16
 ; CHECK-NEXT:    testl %edi, %edi
 ; CHECK-NEXT:    je .LBB0_3
 ; CHECK-NEXT:  # %bb.1: # %if.end
 ; CHECK-NEXT:    callq fn
 ; CHECK-NEXT:    #APP
-; CHECK-NEXT:    # jump to .Ltmp0
+; CHECK-NEXT:    # jump to .LBB0_4
 ; CHECK-NEXT:    #NO_APP
 ; CHECK-NEXT:  # %bb.2: # %return
 ; CHECK-NEXT:    movl $4, %eax
 ; CHECK-NEXT:    popq %rcx
 ; CHECK-NEXT:    .cfi_def_cfa_offset 8
 ; CHECK-NEXT:    retq
 ; CHECK-NEXT:  .LBB0_3: # %ret0
 ; CHECK-NEXT:    .cfi_def_cfa_offset 16
 ; CHECK-NEXT:    xorl %eax, %eax
 ; CHECK-NEXT:    popq %rcx
 ; CHECK-NEXT:    .cfi_def_cfa_offset 8
 ; CHECK-NEXT:    retq
-; CHECK-NEXT:  .Ltmp0: # Block address taken
-; CHECK-NEXT:  .LBB0_4: # %two
+; CHECK-NEXT:  .LBB0_4: # Block address taken
+; CHECK-NEXT:    # %two
+; CHECK-NEXT:    # Label of block must be emitted
 ; CHECK-NEXT:    .cfi_def_cfa_offset 16
 ; CHECK-NEXT:    popq %rax
 ; CHECK-NEXT:    .cfi_def_cfa_offset 8
 ; CHECK-NEXT:    jmp fn # TAILCALL
 entry:
   %tobool = icmp eq i32 %v, 0
   br i1 %tobool, label %ret0, label %if.end
 

llvm/test/CodeGen/X86/tail-dup-asm-goto.ll

 ; NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
 ; RUN: llc -mtriple=x86_64-linux -stop-after=early-tailduplication < %s | FileCheck %s
 
 ; Ensure that we don't duplicate a block with an "INLINEASM_BR" instruction
 ; during code gen.
 declare dso_local void @foo()
 
 define ptr @test1(ptr %arg1, ptr %arg2) {
   ; CHECK-LABEL: name: test1
   ; CHECK: bb.0.bb:
   ; CHECK-NEXT:   successors: %bb.1(0x50000000), %bb.2(0x30000000)
   ; CHECK-NEXT:   liveins: $rdi, $rsi
   ; CHECK-NEXT: {{  $}}
   ; CHECK-NEXT:   [[COPY:%[0-9]+]]:gr64 = COPY $rsi
   ; CHECK-NEXT:   [[COPY1:%[0-9]+]]:gr64 = COPY $rdi
   ; CHECK-NEXT:   [[MOV64rm:%[0-9]+]]:gr64 = MOV64rm [[COPY1]], 1, $noreg, 0, $noreg :: (load (s64) from %ir.arg1)
   ; CHECK-NEXT:   [[SUB64rr:%[0-9]+]]:gr64 = SUB64rr [[MOV64rm]], [[COPY]], implicit-def $eflags
   ; CHECK-NEXT:   JCC_1 %bb.2, 4, implicit $eflags
   ; CHECK-NEXT:   JMP_1 %bb.1
define ptr @test1(ptr %arg1, ptr %arg2) {
   ; CHECK-NEXT:   ADJCALLSTACKDOWN64 0, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
   ; CHECK-NEXT:   CALL64pcrel32 @foo, csr_64, implicit $rsp, implicit $ssp, implicit-def $rsp, implicit-def $ssp
   ; CHECK-NEXT:   ADJCALLSTACKUP64 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
   ; CHECK-NEXT: {{  $}}
   ; CHECK-NEXT: bb.3.bb110:
   ; CHECK-NEXT:   successors: %bb.5(0x80000000), %bb.4(0x00000000)
   ; CHECK-NEXT: {{  $}}
   ; CHECK-NEXT:   [[PHI:%[0-9]+]]:gr64 = PHI [[COPY]], %bb.2, [[MOV64rm]], %bb.1
-  ; CHECK-NEXT:   INLINEASM_BR &"#$0 $1 $2", 9 /* sideeffect mayload attdialect */, 13 /* imm */, 42, 13 /* imm */, 0, 13 /* imm */, blockaddress(@test1, %ir-block.bb17.i.i.i), 12 /* clobber */, implicit-def early-clobber $df, 12 /* clobber */, implicit-def early-clobber $fpsw, 12 /* clobber */, implicit-def early-clobber $eflags
+  ; CHECK-NEXT:   INLINEASM_BR &"#$0 $1 $2", 9 /* sideeffect mayload attdialect */, 13 /* imm */, 42, 13 /* imm */, 0, 13 /* imm */, %bb.4, 12 /* clobber */, implicit-def early-clobber $df, 12 /* clobber */, implicit-def early-clobber $fpsw, 12 /* clobber */, implicit-def early-clobber $eflags
   ; CHECK-NEXT:   JMP_1 %bb.5
   ; CHECK-NEXT: {{  $}}
-  ; CHECK-NEXT: bb.4.bb17.i.i.i (machine-block-address-taken, ir-block-address-taken %ir-block.bb17.i.i.i, inlineasm-br-indirect-target):
+  ; CHECK-NEXT: bb.4.bb17.i.i.i (machine-block-address-taken, inlineasm-br-indirect-target):
   ; CHECK-NEXT:   successors: %bb.5(0x80000000)
   ; CHECK-NEXT: {{  $}}
   ; CHECK-NEXT: {{  $}}
   ; CHECK-NEXT: bb.5.kmem_cache_has_cpu_partial.exit:
   ; CHECK-NEXT:   $rax = COPY [[PHI]]
   ; CHECK-NEXT:   RET 0, $rax
 bb:
   %i28.i = load ptr, ptr %arg1, align 8