Vendor import of llvm-project main llvmorg-17-init-19304-gd0b54bb50e51,vendor/llvm-project/llvmorg-17-init-19304-gd0b54bb50e51

the last commit before the upstream release/17.x branch was created.

1 files changed, 62 insertions, 23 deletions

diff --git a/llvm/utils/TableGen/InfoByHwMode.h b/llvm/utils/TableGen/InfoByHwMode.h
index 44927d0bf0df..b8a6645baca5 100644
--- a/llvm/utils/TableGen/InfoByHwMode.h
+++ b/llvm/utils/TableGen/InfoByHwMode.h
@@ -16,10 +16,16 @@
 
 #include "CodeGenHwModes.h"
 #include "llvm/ADT/SmallSet.h"
-#include "llvm/Support/MachineValueType.h"
-
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/CodeGen/MachineValueType.h"
+#include "llvm/Support/Compiler.h"
+#include <cassert>
+#include <limits>
 #include <map>
 #include <string>
+#include <tuple>
+#include <utility>
 
 namespace llvm {
 
@@ -38,18 +44,44 @@ template <typename InfoT>
 void union_modes(const InfoByHwMode<InfoT> &A,
                  const InfoByHwMode<InfoT> &B,
                  SmallVectorImpl<unsigned> &Modes) {
-  SmallSet<unsigned, 4> U;
-  for (const auto &P : A)
-    U.insert(P.first);
-  for (const auto &P : B)
-    U.insert(P.first);
-  // Make sure that the default mode is last on the list.
+  auto AI = A.begin();
+  auto BI = B.begin();
+
+  // Skip default mode, but remember if we had one.
   bool HasDefault = false;
-  for (unsigned M : U)
-    if (M != DefaultMode)
-      Modes.push_back(M);
-    else
-      HasDefault = true;
+  if (AI != A.end() && AI->first == DefaultMode) {
+    HasDefault = true;
+    ++AI;
+  }
+  if (BI != B.end() && BI->first == DefaultMode) {
+    HasDefault = true;
+    ++BI;
+  }
+
+  while (AI != A.end()) {
+    // If we're done with B, finish A.
+    if (BI == B.end()) {
+      for (; AI != A.end(); ++AI)
+        Modes.push_back(AI->first);
+      break;
+    }
+
+    if (BI->first < AI->first) {
+      Modes.push_back(BI->first);
+      ++BI;
+    } else {
+      Modes.push_back(AI->first);
+      if (AI->first == BI->first)
+        ++BI;
+      ++AI;
+    }
+  }
+
+  // Finish B.
+  for (; BI != B.end(); ++BI)
+    Modes.push_back(BI->first);
+
+  // Make sure that the default mode is last on the list.
   if (HasDefault)
     Modes.push_back(DefaultMode);
 }
@@ -78,20 +110,27 @@ struct InfoByHwMode {
   LLVM_ATTRIBUTE_ALWAYS_INLINE
   bool hasMode(unsigned M) const { return Map.find(M) != Map.end(); }
   LLVM_ATTRIBUTE_ALWAYS_INLINE
-  bool hasDefault() const { return hasMode(DefaultMode); }
+  bool hasDefault() const {
+    return !Map.empty() && Map.begin()->first == DefaultMode;
+  }
 
   InfoT &get(unsigned Mode) {
-    if (!hasMode(Mode)) {
-      assert(hasMode(DefaultMode));
-      Map.insert({Mode, Map.at(DefaultMode)});
-    }
-    return Map.at(Mode);
+    auto F = Map.find(Mode);
+    if (F != Map.end())
+      return F->second;
+
+    // Copy and insert the default mode which should be first.
+    assert(hasDefault());
+    auto P = Map.insert({Mode, Map.begin()->second});
+    return P.first->second;
   }
   const InfoT &get(unsigned Mode) const {
     auto F = Map.find(Mode);
-    if (Mode != DefaultMode && F == Map.end())
-      F = Map.find(DefaultMode);
-    assert(F != Map.end());
+    if (F != Map.end())
+      return F->second;
+    // Get the default mode which should be first.
+    F = Map.begin();
+    assert(F != Map.end() && F->first == DefaultMode);
     return F->second;
   }
 
@@ -100,7 +139,7 @@ struct InfoByHwMode {
     return Map.size() == 1 && Map.begin()->first == DefaultMode;
   }
   LLVM_ATTRIBUTE_ALWAYS_INLINE
-  InfoT getSimple() const {
+  const InfoT &getSimple() const {
     assert(isSimple());
     return Map.begin()->second;
   }