[llvm-commits] [llvm] r115684 - in /llvm/trunk: lib/MC/ELFObjectWriter.cpp test/MC/ELF/size.s

[Rafael Espindola]

Author: rafael
Date: Tue Oct  5 16:02:45 2010
New Revision: 115684

URL: http://llvm.org/viewvc/llvm-project?rev=115684&view=rev
Log:
Don't crash in a strange .size directive.

Added:
    llvm/trunk/test/MC/ELF/size.s
Modified:
    llvm/trunk/lib/MC/ELFObjectWriter.cpp

Modified: llvm/trunk/lib/MC/ELFObjectWriter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/ELFObjectWriter.cpp?rev=115684&r1=115683&r2=115684&view=diff
==============================================================================
--- llvm/trunk/lib/MC/ELFObjectWriter.cpp (original)
+++ llvm/trunk/lib/MC/ELFObjectWriter.cpp Tue Oct  5 16:02:45 2010
@@ -445,12 +445,22 @@
       const MCBinaryExpr *BE = static_cast<const MCBinaryExpr *>(ESize);
 
       if (BE->EvaluateAsRelocatable(Res, &Layout)) {
-        MCSymbolData &A =
-          Layout.getAssembler().getSymbolData(Res.getSymA()->getSymbol());
-        MCSymbolData &B =
-          Layout.getAssembler().getSymbolData(Res.getSymB()->getSymbol());
+        uint64_t AddressA = 0;
+        uint64_t AddressB = 0;
+        const MCSymbol &SymA = Res.getSymA()->getSymbol();
+        const MCSymbol &SymB = Res.getSymB()->getSymbol();
+
+        if (SymA.isDefined()) {
+          MCSymbolData &A = Layout.getAssembler().getSymbolData(SymA);
+          AddressA = Layout.getSymbolAddress(&A);
+        }
+
+        if (SymB.isDefined()) {
+          MCSymbolData &B = Layout.getAssembler().getSymbolData(SymB);
+          AddressB = Layout.getSymbolAddress(&B);
+        }
 
-        Size = Layout.getSymbolAddress(&A) - Layout.getSymbolAddress(&B);
+        Size = AddressA - AddressB;
       }
     } else if (ESize->getKind() == MCExpr::Constant) {
       Size = static_cast<const MCConstantExpr *>(ESize)->getValue();

Added: llvm/trunk/test/MC/ELF/size.s
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/MC/ELF/size.s?rev=115684&view=auto
==============================================================================
--- llvm/trunk/test/MC/ELF/size.s (added)
+++ llvm/trunk/test/MC/ELF/size.s Tue Oct  5 16:02:45 2010
@@ -0,0 +1,9 @@
+// RUN: llvm-mc -filetype=obj -triple x86_64-pc-linux-gnu %s -o - | elf-dump  | FileCheck %s
+
+// Mostly a test that this doesn't crash anymore.
+
+// CHECK:        # Symbol 4
+// CHECK-NEXT:    (('st_name', 1) # 'foo'
+// CHECK-NEXT:     ('st_bind', 1)
+
+	.size	foo, .Lbar-foo