[llvm-commits] CVS: llvm/lib/Target/X86/X86ISelLowering.cpp X86ISelLowering.h

[Chris Lattner]

Changes in directory llvm/lib/Target/X86:

X86ISelLowering.cpp updated: 1.382 -> 1.383
X86ISelLowering.h updated: 1.94 -> 1.95
---
Log message:

implement the new addressing mode description hook.


---
Diffs of the changes:  (+49 -0)

 X86ISelLowering.cpp |   45 +++++++++++++++++++++++++++++++++++++++++++++
 X86ISelLowering.h   |    4 ++++
 2 files changed, 49 insertions(+)


Index: llvm/lib/Target/X86/X86ISelLowering.cpp
diff -u llvm/lib/Target/X86/X86ISelLowering.cpp:1.382 llvm/lib/Target/X86/X86ISelLowering.cpp:1.383
--- llvm/lib/Target/X86/X86ISelLowering.cpp:1.382	Tue Mar 27 20:02:54 2007
+++ llvm/lib/Target/X86/X86ISelLowering.cpp	Fri Mar 30 18:15:24 2007
@@ -4047,6 +4047,51 @@
   }
 }
 
+// isLegalAddressingMode - Return true if the addressing mode represented
+// by AM is legal for this target, for a load/store of the specified type.
+bool X86TargetLowering::isLegalAddressingMode(const AddrMode &AM, 
+                                              const Type *Ty) const {
+  // X86 supports extremely general addressing modes.
+  
+  // X86 allows a sign-extended 32-bit immediate field as a displacement.
+  if (AM.BaseOffs <= -(1LL << 32) || AM.BaseOffs >= (1LL << 32)-1)
+    return false;
+  
+  if (AM.BaseGV) {
+    // X86-64 only supports addr of globals in small code model.
+    if (Subtarget->is64Bit() &&
+        getTargetMachine().getCodeModel() != CodeModel::Small)
+      return false;
+    
+    // We can only fold this if we don't need a load either.
+    if (Subtarget->GVRequiresExtraLoad(AM.BaseGV, getTargetMachine(), false))
+      return false;
+  }
+  
+  switch (AM.Scale) {
+  case 0:
+  case 1:
+  case 2:
+  case 4:
+  case 8:
+    // These scales always work.
+    break;
+  case 3:
+  case 5:
+  case 9:
+    // These scales are formed with basereg+scalereg.  Only accept if there is
+    // no basereg yet.
+    if (AM.HasBaseReg)
+      return false;
+    break;
+  default:  // Other stuff never works.
+    return false;
+  }
+  
+  return true;
+}
+
+
 /// isLegalAddressImmediate - Return true if the integer value can be used
 /// as the offset of the target addressing mode for load / store of the
 /// given type.


Index: llvm/lib/Target/X86/X86ISelLowering.h
diff -u llvm/lib/Target/X86/X86ISelLowering.h:1.94 llvm/lib/Target/X86/X86ISelLowering.h:1.95
--- llvm/lib/Target/X86/X86ISelLowering.h:1.94	Sat Mar 24 21:14:49 2007
+++ llvm/lib/Target/X86/X86ISelLowering.h	Fri Mar 30 18:15:24 2007
@@ -335,6 +335,10 @@
       getRegForInlineAsmConstraint(const std::string &Constraint,
                                    MVT::ValueType VT) const;
     
+    /// isLegalAddressingMode - Return true if the addressing mode represented
+    /// by AM is legal for this target, for a load/store of the specified type.
+    virtual bool isLegalAddressingMode(const AddrMode &AM, const Type *Ty)const;
+
     /// isLegalAddressImmediate - Return true if the integer value can be used
     /// as the offset of the target addressing mode for load / store of the
     /// given type.