[JITLink] Add LinkGraph name / triple to debugging output. (#161772)

Adds the name and triple of the graph to LinkGraph::dump output before
the rest of the graph content. Calls from JITLinkGeneric.cpp to dump the
graph are updated to avoid redundantly naming the graph.

Author: lhames

llvm/lib/ExecutionEngine/JITLink/JITLink.cpp

@@ -280,6 +280,9 @@ std::vector<Block *> LinkGraph::splitBlockImpl(std::vector<Block *> Blocks,
 void LinkGraph::dump(raw_ostream &OS) {
   DenseMap<Block *, std::vector<Symbol *>> BlockSymbols;
 
+  OS << "LinkGraph \"" << getName()
+     << "\" (triple = " << getTargetTriple().str() << ")\n";
+
   // Map from blocks to the symbols pointing at them.
   for (auto *Sym : defined_symbols())
     BlockSymbols[&Sym->getBlock()].push_back(Sym);

llvm/lib/ExecutionEngine/JITLink/JITLinkGeneric.cpp

@@ -21,23 +21,21 @@ JITLinkerBase::~JITLinkerBase() = default;
 
 void JITLinkerBase::linkPhase1(std::unique_ptr<JITLinkerBase> Self) {
 
-  LLVM_DEBUG({
-    dbgs() << "Starting link phase 1 for graph " << G->getName() << "\n";
-  });
+  LLVM_DEBUG(dbgs() << "Starting link phase 1\n");
 
   // Prune and optimize the graph.
   if (auto Err = runPasses(Passes.PrePrunePasses))
     return Ctx->notifyFailed(std::move(Err));
 
   LLVM_DEBUG({
-    dbgs() << "Link graph \"" << G->getName() << "\" pre-pruning:\n";
+    dbgs() << "Link graph pre-pruning:\n";
     G->dump(dbgs());
   });
 
   prune(*G);
 
   LLVM_DEBUG({
-    dbgs() << "Link graph \"" << G->getName() << "\" post-pruning:\n";
+    dbgs() << "Link graph post-pruning:\n";
     G->dump(dbgs());
   });
 
@@ -67,14 +65,15 @@ void JITLinkerBase::linkPhase1(std::unique_ptr<JITLinkerBase> Self) {
 void JITLinkerBase::linkPhase2(std::unique_ptr<JITLinkerBase> Self,
                                AllocResult AR) {
 
+  LLVM_DEBUG(dbgs() << "Starting link phase 2\n");
+
   if (AR)
     Alloc = std::move(*AR);
   else
     return Ctx->notifyFailed(AR.takeError());
 
   LLVM_DEBUG({
-    dbgs() << "Link graph \"" << G->getName()
-           << "\" before post-allocation passes:\n";
+    dbgs() << "Link graph before post-allocation passes:\n";
     G->dump(dbgs());
   });
 
@@ -131,9 +130,7 @@ void JITLinkerBase::linkPhase2(std::unique_ptr<JITLinkerBase> Self,
 void JITLinkerBase::linkPhase3(std::unique_ptr<JITLinkerBase> Self,
                                Expected<AsyncLookupResult> LR) {
 
-  LLVM_DEBUG({
-    dbgs() << "Starting link phase 3 for graph " << G->getName() << "\n";
-  });
+  LLVM_DEBUG(dbgs() << "Starting link phase 3\n");
 
   // If the lookup failed, bail out.
   if (!LR)
@@ -143,16 +140,15 @@ void JITLinkerBase::linkPhase3(std::unique_ptr<JITLinkerBase> Self,
   applyLookupResult(*LR);
 
   LLVM_DEBUG({
-    dbgs() << "Link graph \"" << G->getName()
-           << "\" before pre-fixup passes:\n";
+    dbgs() << "Link graph before pre-fixup passes:\n";
     G->dump(dbgs());
   });
 
   if (auto Err = runPasses(Passes.PreFixupPasses))
     return abandonAllocAndBailOut(std::move(Self), std::move(Err));
 
   LLVM_DEBUG({
-    dbgs() << "Link graph \"" << G->getName() << "\" before copy-and-fixup:\n";
+    dbgs() << "Link graph before copy-and-fixup:\n";
     G->dump(dbgs());
   });
 
@@ -161,7 +157,7 @@ void JITLinkerBase::linkPhase3(std::unique_ptr<JITLinkerBase> Self,
     return abandonAllocAndBailOut(std::move(Self), std::move(Err));
 
   LLVM_DEBUG({
-    dbgs() << "Link graph \"" << G->getName() << "\" after copy-and-fixup:\n";
+    dbgs() << "Link graph after copy-and-fixup:\n";
     G->dump(dbgs());
   });
 
@@ -186,16 +182,14 @@ void JITLinkerBase::linkPhase3(std::unique_ptr<JITLinkerBase> Self,
 void JITLinkerBase::linkPhase4(std::unique_ptr<JITLinkerBase> Self,
                                FinalizeResult FR) {
 
-  LLVM_DEBUG({
-    dbgs() << "Starting link phase 4 for graph " << G->getName() << "\n";
-  });
+  LLVM_DEBUG(dbgs() << "Starting link phase 4\n");
 
   if (!FR)
     return Ctx->notifyFailed(FR.takeError());
 
   Ctx->notifyFinalized(std::move(*FR));
 
-  LLVM_DEBUG({ dbgs() << "Link of graph " << G->getName() << " complete\n"; });
+  LLVM_DEBUG({ dbgs() << "Link complete\n"; });
 }
 
 Error JITLinkerBase::runPasses(LinkGraphPassList &Passes) {

llvm/test/ExecutionEngine/JITLink/AArch32/ELF_data_alignment.s

@@ -22,7 +22,7 @@
 # CHECK-OBJ: Contents of section .rodata:
 # CHECK-OBJ: 0000 48310048 32004833 00                 H1.H2.H3.
 
-# CHECK-LG: Starting link phase 1 for graph
+# CHECK-LG: Starting link phase 1
 # CHECK-LG: section .rodata:
 
 # CHECK-LG:       block 0x0 size = 0x00000009, align = 1, alignment-offset = 0

llvm/test/ExecutionEngine/JITLink/RISCV/ELF_relax_call.s

@@ -102,7 +102,7 @@ p:
         call o
         .size p, .-p
 
-# CHECK: Link graph "{{.*}}" before copy-and-fixup:
+# CHECK: Link graph before copy-and-fixup:
 # CHECK: section .text:
 # CHECK:   block 0x1000
 # CHECK:     symbols:

llvm/test/ExecutionEngine/JITLink/RISCV/ELF_relax_call_rvc.s

@@ -131,7 +131,7 @@ p:
         call o
         .size p, .-p
 
-# CHECK:      Link graph "{{.*}}" before copy-and-fixup:
+# CHECK:      Link graph before copy-and-fixup:
 # CHECK:      section .text:
 # CHECK:        block 0x1000
 # CHECK:          symbols: