From 12885194955ad4620251ad7aa16c58220967222d Mon Sep 17 00:00:00 2001
From: Manuel Drehwald <git@manuel.drehwald.info>
Date: Sun, 16 Jul 2023 07:53:22 -0400
Subject: [PATCH] simplify and fix blasDiffUse (#1332)

---
 .../tools/enzyme-tblgen/blasDiffUseUpdater.h  | 25 +++----------------
 1 file changed, 4 insertions(+), 21 deletions(-)

diff --git a/enzyme/tools/enzyme-tblgen/blasDiffUseUpdater.h b/enzyme/tools/enzyme-tblgen/blasDiffUseUpdater.h
index 419ae2f321b4..ac6388956081 100644
--- a/enzyme/tools/enzyme-tblgen/blasDiffUseUpdater.h
+++ b/enzyme/tools/enzyme-tblgen/blasDiffUseUpdater.h
@@ -49,20 +49,10 @@ void emit_BLASDiffUse(TGPattern &pattern, llvm::raw_ostream &os) {
   }
 
   emit_scalar_caching(pattern, os);
-  // we currently cache all vecs before we cache all matrices
-  // once fixed we can merge this calls
   for (size_t i = 0; i < nameVec.size(); i++) {
     auto ty = typeMap.lookup(i);
-    if (ty != ArgType::vincData)
+    if (ty != ArgType::vincData && ty != ArgType::mldData)
       continue;
-    assert(typeMap.lookup(i + 1) == ArgType::vincInc);
-    emit_mat_vec_caching(pattern, i, os);
-  }
-  for (size_t i = 0; i < nameVec.size(); i++) {
-    auto ty = typeMap.lookup(i);
-    if (ty != ArgType::mldData)
-      continue;
-    assert(typeMap.lookup(i + 1) == ArgType::mldLD);
     emit_mat_vec_caching(pattern, i, os);
   }
 
@@ -70,16 +60,9 @@ void emit_BLASDiffUse(TGPattern &pattern, llvm::raw_ostream &os) {
     auto users = argUsers.lookup(argPos);
     auto name = nameVec[argPos];
     size_t i = (lv23 ? argPos - 1 : argPos);
-    os << "  if (val == arg_" << name << " && !cache_" << name << ") {\n";
-    for (auto a : users) {
-      auto name = nameVec[a];
-      // The following shows that I probably should change the tblgen
-      // logic and the Blas.td declaration
-      if (a == i) // a == i? argpos ?
-        continue;
-      os << "    if (active_" << name << ") return true;\n";
-    }
-    os << "  }\n";
+    os << "  if (val == arg_" << name << " && need_" << name << " && !cache_"
+       << name << ")\n"
+       << "     return true;\n";
   }
 
   os << "  return false;\n";