Add a local stack object block allocation pass. This is still an

experimental pass that allocates locals relative to one another before
register allocation and then assigns them to actual stack slots as a block
later in PEI. This will eventually allow targets with limited index offset
range to allocate additional base registers (not just FP and SP) to
more efficiently reference locals, as well as handle situations where
locals cannot be referenced via SP or FP at all (dynamic stack realignment
together with variable sized objects, for example). It's currently
incomplete and almost certainly buggy. Work in progress.

Disabled by default and gated via the -enable-local-stack-alloc command
line option.

rdar://8277890



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@111059 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 7 insertions, 0 deletions

diff --git a/include/llvm/CodeGen/Passes.h b/include/llvm/CodeGen/Passes.h
index 3e6b3e1..0fa498a 100644
--- a/include/llvm/CodeGen/Passes.h
+++ b/include/llvm/CodeGen/Passes.h
@@ -198,6 +198,13 @@ namespace llvm {
   /// the GCC-style builtin setjmp/longjmp (sjlj) to handling EH control flow.
   FunctionPass *createSjLjEHPass(const TargetLowering *tli);
 
+  /// createLocalStackSlotAllocationPass - This pass assigns local frame
+  /// indices to stack slots relative to one another and allocates
+  /// base registers to access them when it is estimated by the target to
+  /// be out of range of normal frame pointer or stack pointer index
+  /// addressing.
+  FunctionPass *createLocalStackSlotAllocationPass();
+
 } // End llvm namespace
 
 #endif