[llvm-commits] [llvm] r164141 - in /llvm/trunk: include/llvm/MC/MCContext.h lib/MC/MCContext.cpp lib/Target/PowerPC/PPCAsmPrinter.cpp test/CodeGen/PowerPC/2012-09-16-TOC-entry-check.ll

[Roman Divacky]

Author: rdivacky
Date: Tue Sep 18 12:10:37 2012
New Revision: 164141

URL: http://llvm.org/viewvc/llvm-project?rev=164141&view=rev
Log:
Avoid symbol name clash when filling TOC.

Patch by Adhemerval Zanella.

Added:
    llvm/trunk/test/CodeGen/PowerPC/2012-09-16-TOC-entry-check.ll
Modified:
    llvm/trunk/include/llvm/MC/MCContext.h
    llvm/trunk/lib/MC/MCContext.cpp
    llvm/trunk/lib/Target/PowerPC/PPCAsmPrinter.cpp

Modified: llvm/trunk/include/llvm/MC/MCContext.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/MC/MCContext.h?rev=164141&r1=164140&r2=164141&view=diff
==============================================================================
--- llvm/trunk/include/llvm/MC/MCContext.h (original)
+++ llvm/trunk/include/llvm/MC/MCContext.h Tue Sep 18 12:10:37 2012
@@ -183,6 +183,7 @@
 
     /// LookupSymbol - Get the symbol for \p Name, or null.
     MCSymbol *LookupSymbol(StringRef Name) const;
+    MCSymbol *LookupSymbol(const Twine &Name) const;
 
     /// getSymbols - Get a reference for the symbol table for clients that
     /// want to, for example, iterate over all symbols. 'const' because we

Modified: llvm/trunk/lib/MC/MCContext.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCContext.cpp?rev=164141&r1=164140&r2=164141&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCContext.cpp (original)
+++ llvm/trunk/lib/MC/MCContext.cpp Tue Sep 18 12:10:37 2012
@@ -153,6 +153,12 @@
   return Symbols.lookup(Name);
 }
 
+MCSymbol *MCContext::LookupSymbol(const Twine &Name) const {
+  SmallString<128> NameSV;
+  Name.toVector(NameSV);
+  return LookupSymbol(NameSV.str());
+}
+
 //===----------------------------------------------------------------------===//
 // Section Management
 //===----------------------------------------------------------------------===//

Modified: llvm/trunk/lib/Target/PowerPC/PPCAsmPrinter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/PowerPC/PPCAsmPrinter.cpp?rev=164141&r1=164140&r2=164141&view=diff
==============================================================================
--- llvm/trunk/lib/Target/PowerPC/PPCAsmPrinter.cpp (original)
+++ llvm/trunk/lib/Target/PowerPC/PPCAsmPrinter.cpp Tue Sep 18 12:10:37 2012
@@ -368,9 +368,14 @@
     else if (MO.isJTI())
       MOSymbol = GetJTISymbol(MO.getIndex());
     MCSymbol *&TOCEntry = TOC[MOSymbol];
-    if (TOCEntry == 0)
-      TOCEntry = GetTempSymbol("C", TOCLabelID++);
-    
+    // To avoid name clash check if the name already exists.
+    while (TOCEntry == 0) {
+      if (OutContext.LookupSymbol(Twine(MAI->getPrivateGlobalPrefix()) +
+                                  "C" + Twine(TOCLabelID++)) == 0) {
+        TOCEntry = GetTempSymbol("C", TOCLabelID);
+      }
+    }
+
     const MCExpr *Exp =
       MCSymbolRefExpr::Create(TOCEntry, MCSymbolRefExpr::VK_PPC_TOC_ENTRY,
                               OutContext);

Added: llvm/trunk/test/CodeGen/PowerPC/2012-09-16-TOC-entry-check.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/PowerPC/2012-09-16-TOC-entry-check.ll?rev=164141&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/PowerPC/2012-09-16-TOC-entry-check.ll (added)
+++ llvm/trunk/test/CodeGen/PowerPC/2012-09-16-TOC-entry-check.ll Tue Sep 18 12:10:37 2012
@@ -0,0 +1,27 @@
+; RUN: llc < %s | FileCheck %s
+target datalayout = "E-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v128:128:128-n32:64"
+target triple = "powerpc64-unknown-linux-gnu"
+
+; This test check if the TOC entry symbol name won't clash with global .LC0
+; and .LC2 symbols defined in the module.
+
+ at .LC0 = internal global [5 x i8] c".LC0\00"
+ at .LC2 = internal global [5 x i8] c".LC2\00"
+
+define i32 @foo(double %X, double %Y) nounwind readnone {
+  ; The 1.0 and 3.0 constants generate two TOC entries
+  %cmp = fcmp oeq double %X, 1.000000e+00
+  %conv = zext i1 %cmp to i32
+  %cmp1 = fcmp oeq double %Y, 3.000000e+00
+  %conv2 = zext i1 %cmp1 to i32
+  %add = add nsw i32 %conv2, %conv
+  ret i32 %add
+}
+
+; Check the creation of 2 .tc entries for both double constants. They
+; should be .LC1 and .LC3 to avoid name clash with global constants
+; .LC0 and .LC2
+; CHECK: .LC{{[13]}}:
+; CHECK-NEXT: .tc {{[\._a-zA-Z0-9]+}}[TC],{{[\._a-zA-Z0-9]+}}
+; CHECK: .LC{{[13]}}:
+; CHECK-NEXT: .tc {{[\._a-zA-Z0-9]+}}[TC],{{[\._a-zA-Z0-9]+}}