Weak non-function symbols were being accessed directly, which is

incorrect, as the chosen representative of the weak symbol may not live
with the code in question. Always indirect the access through the TOC
instead.

Patch by Kyle Butt!

llvm-svn: 253708

1 files changed, 28 insertions, 0 deletions

diff --git a/llvm/lib/Target/PowerPC/PPCSubtarget.cpp b/llvm/lib/Target/PowerPC/PPCSubtarget.cpp
index 58dacca..9a9bdfd 100644
--- a/llvm/lib/Target/PowerPC/PPCSubtarget.cpp
+++ b/llvm/lib/Target/PowerPC/PPCSubtarget.cpp
@@ -210,5 +210,33 @@ bool PPCSubtarget::enableSubRegLiveness() const {
   return UseSubRegLiveness;
 }
 
+unsigned char PPCSubtarget::classifyGlobalReference(
+    const GlobalValue *GV) const {
+  // Note that currently we don't generate non-pic references.
+  // If a caller wants that, this will have to be updated.
+
+  // Large code model always uses the TOC even for local symbols.
+  if (TM.getCodeModel() == CodeModel::Large)
+    return PPCII::MO_PIC_FLAG | PPCII::MO_NLP_FLAG;
+
+  unsigned char flags = PPCII::MO_PIC_FLAG;
+
+  // Only if the relocation mode is PIC do we have to worry about
+  // interposition. In all other cases we can use a slightly looser standard to
+  // decide how to access the symbol.
+  if (TM.getRelocationModel() == Reloc::PIC_) {
+    // If it's local, or it's non-default, it can't be interposed.
+    if (!GV->hasLocalLinkage() &&
+        GV->hasDefaultVisibility()) {
+      flags |= PPCII::MO_NLP_FLAG;
+    }
+    return flags;
+  }
+
+  if (GV->isStrongDefinitionForLinker())
+    return flags;
+  return flags | PPCII::MO_NLP_FLAG;
+}
+
 bool PPCSubtarget::isELFv2ABI() const { return TM.isELFv2ABI(); }
 bool PPCSubtarget::isPPC64() const { return TM.isPPC64(); }