Print GEP offsets as signed values instead of unsigned values. On X86, this

prints:

getelementptr (int* %A, int -1)

as: "(A) - 4" instead of "(A) + 18446744073709551612", which makes the
assembler much happier.

This fixes test/Regression/CodeGen/X86/2005-02-14-IllegalAssembler.ll,
and Benchmarks/Prolangs-C/cdecl with LLC on X86.

llvm-svn: 20183

1 files changed, 7 insertions, 3 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter.cpp b/llvm/lib/CodeGen/AsmPrinter.cpp
index 80f67023f43..4e77a78d81b 100644
--- a/llvm/lib/CodeGen/AsmPrinter.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter.cpp
@@ -78,10 +78,14 @@ void AsmPrinter::emitConstantValueOnly(const Constant *CV) {
       // generate a symbolic expression for the byte address
       const Constant *ptrVal = CE->getOperand(0);
       std::vector<Value*> idxVec(CE->op_begin()+1, CE->op_end());
-      if (uint64_t Offset = TD.getIndexedOffset(ptrVal->getType(), idxVec)) {
-        O << "(";
+      if (int64_t Offset = TD.getIndexedOffset(ptrVal->getType(), idxVec)) {
+        if (Offset)
+          O << "(";
         emitConstantValueOnly(ptrVal);
-        O << ") + " << Offset;
+        if (Offset > 0)
+          O << ") + " << Offset;
+        else if (Offset < 0)
+          O << ") - " << -Offset;
       } else {
         emitConstantValueOnly(ptrVal);
       }