brg
InstSelectSimple.cpp: Add stub implementation of visitFreeInst.
Add comments that mention how we are failing to implement malloc/free.
Add initial implementation of visitAllocaInst.
X86TargetMachine.cpp: Include llvm/Transforms/Scalar.h.
Add LowerAllocations pass before instruction selection.
jello/Makefile: Add scalaropts.a.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@4994 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/InstSelectSimple.cpp b/lib/Target/X86/InstSelectSimple.cpp
index 5247214..79fa8cd 100644
--- a/lib/Target/X86/InstSelectSimple.cpp
+++ b/lib/Target/X86/InstSelectSimple.cpp
@@ -101,6 +101,7 @@
void visitStoreInst(StoreInst &I);
void visitGetElementPtrInst(GetElementPtrInst &I);
void visitMallocInst(MallocInst &I);
+ void visitFreeInst(FreeInst &I);
void visitAllocaInst(AllocaInst &I);
// Other operators
@@ -885,6 +886,20 @@
void
ISel::visitMallocInst (MallocInst &I)
{
+ // We assume that by this point, malloc instructions have been
+ // lowered to calls, and dlsym will magically find malloc for us.
+ // So we do not want to see malloc instructions here.
+ visitInstruction (I);
+}
+
+
+/// visitFreeInst - same story as MallocInst
+void
+ISel::visitFreeInst (FreeInst &I)
+{
+ // We assume that by this point, free instructions have been
+ // lowered to calls, and dlsym will magically find free for us.
+ // So we do not want to see free instructions here.
visitInstruction (I);
}
@@ -894,7 +909,18 @@
void
ISel::visitAllocaInst (AllocaInst &I)
{
- visitInstruction (I);
+ // Find the data size of the alloca inst's getAllocatedType.
+ const Type *allocatedType = I.getAllocatedType ();
+ const TargetData &TD = TM.DataLayout;
+ unsigned allocatedTypeSize = TD.getTypeSize (allocatedType);
+ // Keep stack 32-bit aligned.
+ unsigned int allocatedTypeWords = allocatedTypeSize / 4;
+ if (allocatedTypeSize % 4 != 0) { allocatedTypeWords++; }
+ // Subtract size from stack pointer, thereby allocating some space.
+ BuildMI (BB, X86::SUBri32, 1, X86::ESP).addZImm (allocatedTypeWords * 4);
+ // Put a pointer to the space into the result register, by copying
+ // the stack pointer.
+ BuildMI (BB, X86::MOVrr32, 1, getReg (I)).addReg (X86::ESP);
}