[llvm] [DebugInfo][DWARF] Add heapallocsite information (PR #132073)

[Jann Horn via llvm-commits]

thejh wrote:

I have now rebased the patch; sorry, it changed a little bit since I merge-conflicted with myself. The interdiff between the old and new version is:
```diff
@@ llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp: DIE &DwarfCompileUnit::constru
                      getDwarf5OrGNUAttr(dwarf::DW_AT_call_return_pc), PCAddr);
    }

-+  if (AllocSiteTy) {
++  if (AllocSiteTy)
 +    addType(CallSiteDIE, AllocSiteTy, dwarf::DW_AT_LLVM_alloc_type);
-+  }
 +
    return CallSiteDIE;
  }
@@ llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp: void DwarfDebug::constructCallSiteEn
        // If this is a direct call, find the callee's subprogram.
        // In the case of an indirect call find the register that holds
        // the callee.
-       const MachineOperand &CalleeOp = TII->getCalleeOperand(MI);
--      if (!CalleeOp.isGlobal() &&
--          (!CalleeOp.isReg() || !CalleeOp.getReg().isPhysical()))
+@@ llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp: void DwarfDebug::constructCallSiteEntryDIEs(const DISubprogram &SP,
+         PhysRegCalleeOperand =
+             PhysRegCalleeOperand && MCOI.OperandType == MCOI::OPERAND_REGISTER;
+       }
+-      if (!CalleeOp.isGlobal() && !PhysRegCalleeOperand)
 -        continue;

        unsigned CallReg = 0;
        const DISubprogram *CalleeSP = nullptr;
        const Function *CalleeDecl = nullptr;
--      if (CalleeOp.isReg()) {
+       if (PhysRegCalleeOperand) {
 -        CallReg = CalleeOp.getReg();
 -        if (!CallReg)
 -          continue;
 -      } else {
-+      if (CalleeOp.isReg() && CalleeOp.getReg().isPhysical()) {
 +        CallReg = CalleeOp.getReg(); // might be zero
 +      } else if (CalleeOp.isGlobal()) {
          CalleeDecl = dyn_cast<Function>(CalleeOp.getGlobal());
```

https://github.com/llvm/llvm-project/pull/132073