AMDGPU/R600: Fix GlobalValue regressions.

Don't cast GV expression to MCSymbolRefExpr. r272705 changed GV to binary
expressions by including offset even if the offset it 0
(we haven't hit this sooner since tested workloads don't include static offsets)
We don't really care about the type of expression, so set it directly.
Fixes: r272705

Consider section relative relocations. Since all const as data is in one boffer section relative is equivalent to abs32.
Fixes: r273166

Differential Revision: http://reviews.llvm.org/D21633

llvm-svn: 273785

2 files changed, 3 insertions, 2 deletions

diff --git a/llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUELFObjectWriter.cpp b/llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUELFObjectWriter.cpp
index 6031522b0d6..b4e3b8e896b 100644
--- a/llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUELFObjectWriter.cpp
+++ b/llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUELFObjectWriter.cpp
@@ -56,6 +56,8 @@ unsigned AMDGPUELFObjectWriter::getRelocType(MCContext &Ctx,
   default: break;
   case FK_PCRel_4:
     return ELF::R_AMDGPU_REL32;
+  case FK_SecRel_4:
+    return ELF::R_AMDGPU_ABS32;
   }
 
   llvm_unreachable("unhandled relocation type");
diff --git a/llvm/lib/Target/AMDGPU/MCTargetDesc/R600MCCodeEmitter.cpp b/llvm/lib/Target/AMDGPU/MCTargetDesc/R600MCCodeEmitter.cpp
index 381ef011cac..5e8e6ceb7ca 100644
--- a/llvm/lib/Target/AMDGPU/MCTargetDesc/R600MCCodeEmitter.cpp
+++ b/llvm/lib/Target/AMDGPU/MCTargetDesc/R600MCCodeEmitter.cpp
@@ -163,7 +163,6 @@ uint64_t R600MCCodeEmitter::getMachineOpValue(const MCInst &MI,
   }
 
   if (MO.isExpr()) {
-    const MCSymbolRefExpr *Expr = cast<MCSymbolRefExpr>(MO.getExpr());
     // We put rodata at the end of code section, then map the entire
     // code secetion as vtx buf. Thus the section relative address is the
     // correct one.
@@ -171,7 +170,7 @@ uint64_t R600MCCodeEmitter::getMachineOpValue(const MCInst &MI,
     // We can't easily get the order of the current one, so compare against
     // the first one and adjust offset.
     const unsigned offset = (&MO == &MI.getOperand(0)) ? 0 : 4;
-    Fixups.push_back(MCFixup::create(offset, Expr, FK_SecRel_4, MI.getLoc()));
+    Fixups.push_back(MCFixup::create(offset, MO.getExpr(), FK_SecRel_4, MI.getLoc()));
     return 0;
   }