From f98bccf06f3a54d1db08e9fb58bba0e08ebaf4e4 Mon Sep 17 00:00:00 2001
From: Sam Clegg <sbc@chromium.org>
Date: Sat, 13 Jan 2018 15:57:48 +0000
Subject: [PATCH] Revert "[WebAssembly] Move checking of InputSegment comdat
 group earlier"

This reverts commit 7421eab7ccf2e14518f4526a084a5afc76ac9c6a.

llvm-svn: 322441
---
 lld/wasm/OutputSegment.h | 7 -------
 lld/wasm/Writer.cpp      | 7 ++++++-
 2 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/lld/wasm/OutputSegment.h b/lld/wasm/OutputSegment.h
index 420d9744165e..9825ce8e6975 100644
--- a/lld/wasm/OutputSegment.h
+++ b/lld/wasm/OutputSegment.h
@@ -25,18 +25,12 @@ public:
 
   void addInputSegment(InputSegment *Segment) {
     Alignment = std::max(Alignment, Segment->getAlignment());
-    if (InputSegments.empty())
-      Comdat = Segment->getComdat();
-    else
-      assert(Comdat == Segment->getComdat());
     InputSegments.push_back(Segment);
     Size = llvm::alignTo(Size, Segment->getAlignment());
     Segment->setOutputSegment(this, Size);
     Size += Segment->getSize();
   }
 
-  StringRef getComdat() const { return Comdat; }
-
   uint32_t getSectionOffset() const { return SectionOffset; }
 
   void setSectionOffset(uint32_t Offset) { SectionOffset = Offset; }
@@ -53,7 +47,6 @@ public:
   std::string Header;
 
 private:
-  StringRef Comdat;
   uint32_t SectionOffset = 0;
 };
 
diff --git a/lld/wasm/Writer.cpp b/lld/wasm/Writer.cpp
index 07b7b076102f..bb34f265d407 100644
--- a/lld/wasm/Writer.cpp
+++ b/lld/wasm/Writer.cpp
@@ -439,7 +439,12 @@ void Writer::createLinkingSection() {
           ComdatEntry{WASM_COMDAT_FUNCTION, F->getOutputIndex()});
   }
   for (uint32_t I = 0; I < Segments.size(); ++I) {
-    StringRef Comdat = Segments[I]->getComdat();
+    const auto &InputSegments = Segments[I]->InputSegments;
+    if (InputSegments.empty())
+      continue;
+    StringRef Comdat = InputSegments[0]->getComdat();
+    for (const InputSegment *IS : InputSegments)
+      assert(IS->getComdat() == Comdat);
     if (!Comdat.empty())
       Comdats[Comdat].emplace_back(ComdatEntry{WASM_COMDAT_DATA, I});
   }