DebugInfo: PR14763/r183329 correct the location of indirect parameters

We had been papering over a problem with location info for non-trivial
types passed by value by emitting their type as references (this caused
the debugger to interpret the location information correctly, but broke
the type of the function). r183329 corrected the type information but
lead to the debugger interpreting the pointer parameter as the value -
the debug info describing the location needed an extra dereference.

Use a new flag in DIVariable to add the extra indirection (either by
promoting an existing DW_OP_reg (parameter passed in a register) to
DW_OP_breg + 0 or by adding DW_OP_deref to an existing DW_OP_breg + n
(parameter passed on the stack).

llvm-svn: 184368

1 files changed, 4 insertions, 3 deletions

diff --git a/llvm/lib/Target/ARM/ARMAsmPrinter.cpp b/llvm/lib/Target/ARM/ARMAsmPrinter.cpp
index d917009604c..dd7e20fcd04 100644
--- a/llvm/lib/Target/ARM/ARMAsmPrinter.cpp
+++ b/llvm/lib/Target/ARM/ARMAsmPrinter.cpp
@@ -214,13 +214,14 @@ namespace {
 } // end of anonymous namespace
 
 /// EmitDwarfRegOp - Emit dwarf register operation.
-void ARMAsmPrinter::EmitDwarfRegOp(const MachineLocation &MLoc) const {
+void ARMAsmPrinter::EmitDwarfRegOp(const MachineLocation &MLoc,
+                                   bool Indirect) const {
   const TargetRegisterInfo *RI = TM.getRegisterInfo();
   if (RI->getDwarfRegNum(MLoc.getReg(), false) != -1) {
-    AsmPrinter::EmitDwarfRegOp(MLoc);
+    AsmPrinter::EmitDwarfRegOp(MLoc, Indirect);
     return;
   }
-  assert(MLoc.isReg() &&
+  assert(MLoc.isReg() && !Indirect &&
          "This doesn't support offset/indirection - implement it if needed");
   unsigned Reg = MLoc.getReg();
   if (Reg >= ARM::S0 && Reg <= ARM::S31) {