[CodeGen] Use temp symbol for MBBs (#95031)

Internal label names never occur in the symbol table, so when using an
object streamer, there's no point in constructing these names and then
adding them to hash tables -- they are never visible in the output.

It's not possible to reuse createTempSymbol, because on BPF has a
different prefix for globals and basic blocks right now.

1 files changed, 8 insertions, 8 deletions

diff --git a/llvm/lib/CodeGen/MachineBasicBlock.cpp b/llvm/lib/CodeGen/MachineBasicBlock.cpp
index 16505f2..abf43e3 100644
--- a/llvm/lib/CodeGen/MachineBasicBlock.cpp
+++ b/llvm/lib/CodeGen/MachineBasicBlock.cpp
@@ -80,10 +80,11 @@ MCSymbol *MachineBasicBlock::getSymbol() const {
       }
       CachedMCSymbol = Ctx.getOrCreateSymbol(MF->getName() + Suffix);
     } else {
-      const StringRef Prefix = Ctx.getAsmInfo()->getPrivateLabelPrefix();
-      CachedMCSymbol = Ctx.getOrCreateSymbol(Twine(Prefix) + "BB" +
-                                             Twine(MF->getFunctionNumber()) +
-                                             "_" + Twine(getNumber()));
+      // If the block occurs as label in inline assembly, parsing the assembly
+      // needs an actual label name => set AlwaysEmit in these cases.
+      CachedMCSymbol = Ctx.createBlockSymbol(
+          "BB" + Twine(MF->getFunctionNumber()) + "_" + Twine(getNumber()),
+          /*AlwaysEmit=*/hasLabelMustBeEmitted());
     }
   }
   return CachedMCSymbol;
@@ -104,10 +105,9 @@ MCSymbol *MachineBasicBlock::getEndSymbol() const {
   if (!CachedEndMCSymbol) {
     const MachineFunction *MF = getParent();
     MCContext &Ctx = MF->getContext();
-    auto Prefix = Ctx.getAsmInfo()->getPrivateLabelPrefix();
-    CachedEndMCSymbol = Ctx.getOrCreateSymbol(Twine(Prefix) + "BB_END" +
-                                              Twine(MF->getFunctionNumber()) +
-                                              "_" + Twine(getNumber()));
+    CachedEndMCSymbol = Ctx.createBlockSymbol(
+        "BB_END" + Twine(MF->getFunctionNumber()) + "_" + Twine(getNumber()),
+        /*AlwaysEmit=*/false);
   }
   return CachedEndMCSymbol;
 }