Fix SingleSource/Regression/C/2004-08-12-InlinerAndAllocas.c on Sparc.
The ABI specifies that there is a register save area at the bottom of the
stack, which means the actual used pointer needs to be an offset from
the subtracted value.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26202 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/Sparc/SparcISelDAGToDAG.cpp b/lib/Target/Sparc/SparcISelDAGToDAG.cpp
index dba02c0..8671b60 100644
--- a/lib/Target/Sparc/SparcISelDAGToDAG.cpp
+++ b/lib/Target/Sparc/SparcISelDAGToDAG.cpp
@@ -211,7 +211,7 @@
setOperationAction(ISD::VAEND , MVT::Other, Expand);
setOperationAction(ISD::STACKSAVE , MVT::Other, Expand);
setOperationAction(ISD::STACKRESTORE , MVT::Other, Expand);
- setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32 , Expand);
+ setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32 , Custom);
setOperationAction(ISD::ConstantFP, MVT::f64, Expand);
setOperationAction(ISD::ConstantFP, MVT::f32, Expand);
@@ -807,6 +807,27 @@
return DAG.getNode(ISD::MERGE_VALUES, Tys, Ops);
}
}
+ case ISD::DYNAMIC_STACKALLOC: {
+ SDOperand Chain = Op.getOperand(0); // Legalize the chain.
+ SDOperand Size = Op.getOperand(1); // Legalize the size.
+
+ unsigned SPReg = SP::O6;
+ SDOperand SP = DAG.getCopyFromReg(Chain, SPReg, MVT::i32);
+ SDOperand NewSP = DAG.getNode(ISD::SUB, MVT::i32, SP, Size); // Value
+ Chain = DAG.getCopyToReg(SP.getValue(1), SPReg, NewSP); // Output chain
+
+ // The resultant pointer is actually 16 words from the bottom of the stack,
+ // to provide a register spill area.
+ SDOperand NewVal = DAG.getNode(ISD::ADD, MVT::i32, NewSP,
+ DAG.getConstant(96, MVT::i32));
+ std::vector<MVT::ValueType> Tys;
+ Tys.push_back(MVT::i32);
+ Tys.push_back(MVT::Other);
+ std::vector<SDOperand> Ops;
+ Ops.push_back(NewVal);
+ Ops.push_back(Chain);
+ return DAG.getNode(ISD::MERGE_VALUES, Tys, Ops);
+ }
case ISD::RET: {
SDOperand Copy;