[ARM64] [Windows] Mark block address as taken when expanding catchrets (#109252)

This fixes issue #109250

The issue happens during the `MachineBlockPlacement` pass. The block,
whose address was previously not taken, is deemed redundant by the pass
and subsequently replaced using
`MachineBasicBlock::ReplaceUsesOfBlockWith` in `BranchFolding`.

ReplaceUsesOfBlockWith only replaces uses in the terminator. However,
`expandPostRAPseudo` introduces new block uses when expanding catchrets.
These uses do not get replaced, which results in undefined label errors
later on.

Marking the block addresss as taken prevents the replacement of the
block, without also replacing non-terminator uses.

Author: momo5502

llvm/lib/Target/AArch64/AArch64InstrInfo.cpp

@@ -1994,6 +1994,7 @@ bool AArch64InstrInfo::expandPostRAPseudo(MachineInstr &MI) const {
         .addReg(AArch64::X0)
         .addMBB(TargetMBB)
         .addImm(0);
+    TargetMBB->setMachineBlockAddressTaken();
     return true;
   }
 

llvm/test/CodeGen/AArch64/pr58516.ll

@@ -40,7 +40,8 @@ define void @osfx(ptr %this) comdat personality ptr @__CxxFrameHandler3 {
 ; CHECK-NEXT:  // %bb.1: // %invoke.cont12
 ; CHECK-NEXT:    str wzr, [x20]
 ; CHECK-NEXT:    str wzr, [x21]
-; CHECK-NEXT:  .LBB0_2: // %try.cont
+; CHECK-NEXT:  .LBB0_2: // Block address taken
+; CHECK-NEXT:    // %try.cont
 ; CHECK-NEXT:  $ehgcr_0_2:
 ; CHECK-NEXT:    .seh_startepilogue
 ; CHECK-NEXT:    sub sp, x29, #24

llvm/test/CodeGen/AArch64/wineh-catchret-label-generation.ll

@@ -0,0 +1,97 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple aarch64-unknown-windows-msvc %s -o - | FileCheck %s
+
+declare i32 @__CxxFrameHandler3(...)
+
+declare void @llvm.seh.try.begin() #0
+
+define fastcc ptr @test_function(i1 %0, ptr %_Fmtfl.i.i, i1 %1) personality ptr @__CxxFrameHandler3 {
+; CHECK-LABEL: test_function:
+; CHECK:       .Lfunc_begin0:
+; CHECK-NEXT:  .seh_proc test_function
+; CHECK-NEXT:    .seh_handler __CxxFrameHandler3, @unwind, @except
+; CHECK-NEXT:  // %bb.0: // %entry
+; CHECK-NEXT:    stp x29, x30, [sp, #-32]! // 16-byte Folded Spill
+; CHECK-NEXT:    .seh_save_fplr_x 32
+; CHECK-NEXT:    mov x29, sp
+; CHECK-NEXT:    .seh_set_fp
+; CHECK-NEXT:    .seh_endprologue
+; CHECK-NEXT:    mov x3, #-2 // =0xfffffffffffffffe
+; CHECK-NEXT:    stur x3, [x29, #16]
+; CHECK-NEXT:    tbz w0, #0, .LBB0_3
+; CHECK-NEXT:  // %bb.1: // %invoke.cont.i124
+; CHECK-NEXT:    mov x0, x1
+; CHECK-NEXT:    b .LBB0_4
+; CHECK-NEXT:  .LBB0_2: // Block address taken
+; CHECK-NEXT:    // %some-block
+; CHECK-NEXT:  $ehgcr_0_2:
+; CHECK-NEXT:  .LBB0_3: // %left-block526
+; CHECK-NEXT:    mov x0, xzr
+; CHECK-NEXT:  .LBB0_4: // %common.ret1
+; CHECK-NEXT:    .seh_startepilogue
+; CHECK-NEXT:    ldp x29, x30, [sp], #32 // 16-byte Folded Reload
+; CHECK-NEXT:    .seh_save_fplr_x 32
+; CHECK-NEXT:    .seh_endepilogue
+; CHECK-NEXT:    ret
+; CHECK-NEXT:    .seh_endfunclet
+; CHECK-NEXT:    .seh_handlerdata
+; CHECK-NEXT:    .word ($cppxdata$test_function)@IMGREL
+; CHECK-NEXT:    .text
+; CHECK-NEXT:    .seh_endproc
+; CHECK-NEXT:    .def "?catch$5@?0?test_function@4HA";
+; CHECK-NEXT:    .scl 3;
+; CHECK-NEXT:    .type 32;
+; CHECK-NEXT:    .endef
+; CHECK-NEXT:    .p2align 2
+; CHECK-NEXT:  "?catch$5@?0?test_function@4HA":
+; CHECK-NEXT:  .seh_proc "?catch$5@?0?test_function@4HA"
+; CHECK-NEXT:    .seh_handler __CxxFrameHandler3, @unwind, @except
+; CHECK-NEXT:  .LBB0_5: // %catch.i
+; CHECK-NEXT:    stp x29, x30, [sp, #-16]! // 16-byte Folded Spill
+; CHECK-NEXT:    .seh_save_fplr_x 16
+; CHECK-NEXT:    .seh_endprologue
+; CHECK-NEXT:    adrp x0, .LBB0_2
+; CHECK-NEXT:    add x0, x0, .LBB0_2
+; CHECK-NEXT:    .seh_startepilogue
+; CHECK-NEXT:    ldp x29, x30, [sp], #16 // 16-byte Folded Reload
+; CHECK-NEXT:    .seh_save_fplr_x 16
+; CHECK-NEXT:    .seh_endepilogue
+; CHECK-NEXT:    ret
+entry:
+  br i1 %0, label %right-block527, label %left-block526
+
+common.ret1:
+  %common.ret1.op = phi ptr [ null, %left-block530 ], [ null, %some-block ], [ %_Fmtfl.i.i, %invoke.cont.i124 ], [ null, %left-block526 ]
+  ret ptr %common.ret1.op
+
+invoke.cont.i124:
+  %.not657 = icmp eq i32 1, 0
+  br i1 %.not657, label %some-block, label %common.ret1
+
+catch.dispatch.i:
+  %2 = catchswitch within none [label %catch.i] unwind to caller
+
+catch.i:
+  %3 = catchpad within %2 [ptr null, i32 0, ptr null]
+  catchret from %3 to label %some-block
+
+some-block:
+  br label %common.ret1
+
+left-block526:
+  br i1 %1, label %common.ret1, label %left-block530
+
+right-block527:
+  invoke void @llvm.seh.try.begin()
+          to label %invoke.cont.i124 unwind label %catch.dispatch.i
+
+left-block530:
+  %.not = icmp eq i32 0, 0
+  br label %common.ret1
+}
+
+attributes #0 = { nounwind willreturn memory(write) }
+
+!llvm.module.flags = !{!0}
+
+!0 = !{i32 2, !"eh-asynch", i32 1}

llvm/test/CodeGen/AArch64/wineh-try-catch.ll

@@ -41,7 +41,7 @@
 ; CHECK-LABEL: .Ltmp0:
 ; CHECK:       bl      "?func2@@YAHXZ
 
-; CHECK:        [[CATCHRETDEST:.LBB0_[0-9]+]]:      // %catchret.dest
+; CHECK:        [[CATCHRETDEST:.LBB0_[0-9]+]]:      // Block address taken
 
 ; Check the catch funclet.
 ; CHECK-LABEL: "?catch$4@?0??func@@YAHXZ@4HA":