From 36322c7717f7af5790ea0e64ce3d332e2df15060 Mon Sep 17 00:00:00 2001 From: Dan Gohman Date: Sat, 18 Oct 2008 02:06:02 +0000 Subject: Teach DAGCombine to fold constant offsets into GlobalAddress nodes, and add a TargetLowering hook for it to use to determine when this is legal (i.e. not in PIC mode, etc.) This allows instruction selection to emit folded constant offsets in more cases, such as the included testcase, eliminating the need for explicit arithmetic instructions. This eliminates the need for the C++ code in X86ISelDAGToDAG.cpp that attempted to achieve the same effect, but wasn't as effective. Also, fix handling of offsets in GlobalAddressSDNodes in several places, including changing GlobalAddressSDNode's offset from int to int64_t. The Mips, Alpha, Sparc, and CellSPU targets appear to be unaware of GlobalAddress offsets currently, so set the hook to false on those targets. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57748 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/Sparc/SparcISelLowering.cpp | 6 ++++++ lib/Target/Sparc/SparcISelLowering.h | 2 ++ 2 files changed, 8 insertions(+) (limited to 'lib/Target/Sparc') diff --git a/lib/Target/Sparc/SparcISelLowering.cpp b/lib/Target/Sparc/SparcISelLowering.cpp index e81688e..59e19d5 100644 --- a/lib/Target/Sparc/SparcISelLowering.cpp +++ b/lib/Target/Sparc/SparcISelLowering.cpp @@ -996,3 +996,9 @@ getRegClassForInlineAsmConstraint(const std::string &Constraint, return std::vector(); } + +bool +SparcTargetLowering::isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const { + // The Sparc target isn't yet aware of offsets. + return false; +} diff --git a/lib/Target/Sparc/SparcISelLowering.h b/lib/Target/Sparc/SparcISelLowering.h index ea3171d..a0e3c65 100644 --- a/lib/Target/Sparc/SparcISelLowering.h +++ b/lib/Target/Sparc/SparcISelLowering.h @@ -70,6 +70,8 @@ namespace llvm { std::vector getRegClassForInlineAsmConstraint(const std::string &Constraint, MVT VT) const; + + virtual bool isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const; }; } // end namespace llvm -- cgit v1.1