[Backend] Keep call site info valid through the backend

Handle call instruction replacements and deletions in order to preserve
valid state of the call site info of the MachineFunction.

NOTE: If the call site info is enabled for a new target, the assertion from
the MachineFunction::DeleteMachineInstr() should help to locate places
where the updateCallSiteInfo() should be called in order to preserve valid
state of the call site info.

([10/13] Introduce the debug entry values.)

Co-authored-by: Ananth Sowda <asowda@cisco.com>
Co-authored-by: Nikola Prica <nikola.prica@rt-rk.com>
Co-authored-by: Ivan Baev <ibaev@cisco.com>

Differential Revision: https://reviews.llvm.org/D61062

llvm-svn: 364536

1 files changed, 23 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/MachineFunction.cpp b/llvm/lib/CodeGen/MachineFunction.cpp
index 4394ea29df6..9c75d0fd81e 100644
--- a/llvm/lib/CodeGen/MachineFunction.cpp
+++ b/llvm/lib/CodeGen/MachineFunction.cpp
@@ -363,6 +363,13 @@ MachineInstr &MachineFunction::CloneMachineInstrBundle(MachineBasicBlock &MBB,
 /// ~MachineInstr() destructor must be empty.
 void
 MachineFunction::DeleteMachineInstr(MachineInstr *MI) {
+  // Verify that a call site info is at valid state. This assertion should
+  // be triggered during the implementation of support for the
+  // call site info of a new architecture. If the assertion is triggered,
+  // back trace will tell where to insert a call to updateCallSiteInfo().
+  assert((!MI->isCall(MachineInstr::IgnoreBundle) ||
+          CallSitesInfo.find(MI) == CallSitesInfo.end()) &&
+         "Call site info was not updated!");
   // Strip it for parts. The operand array and the MI object itself are
   // independently recyclable.
   if (MI->Operands)
@@ -826,6 +833,22 @@ void MachineFunction::addCodeViewHeapAllocSite(MachineInstr *I, MDNode *MD) {
   CodeViewHeapAllocSites.push_back(std::make_tuple(BeginLabel, EndLabel, DI));
 }
 
+void MachineFunction::updateCallSiteInfo(const MachineInstr *Old,
+                                         const MachineInstr *New) {
+  if (!Target.Options.EnableDebugEntryValues || Old == New)
+    return;
+
+  assert(Old->isCall() && (!New || New->isCall()) &&
+         "Call site info referes only to call instructions!");
+  CallSiteInfoMap::iterator CSIt = CallSitesInfo.find(Old);
+  if (CSIt == CallSitesInfo.end())
+    return;
+  CallSiteInfo CSInfo = std::move(CSIt->second);
+  CallSitesInfo.erase(CSIt);
+  if (New)
+    CallSitesInfo[New] = CSInfo;
+}
+
 /// \}
 
 //===----------------------------------------------------------------------===//