From: Alkis Evlogimenos <alkis@evlogimenos.com>
Date: Tue, 21 Sep 2004 21:22:11 +0000 (+0000)
Subject: The real x87 floating point registers should not be allocatable. They
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=65cbfa0f370f70bb5bd57c084fd73dde6fa35cee;p=oota-llvm.git

The real x87 floating point registers should not be allocatable. They
are only used by the stackifier when transforming FPn register
allocations to the real stack file x87 registers.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16472 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/X86/X86RegisterInfo.td b/lib/Target/X86/X86RegisterInfo.td
index 4262a9ffd70..628a239d014 100644
--- a/lib/Target/X86/X86RegisterInfo.td
+++ b/lib/Target/X86/X86RegisterInfo.td
@@ -86,5 +86,13 @@ def R32 : RegisterClass<i32, 32, [EAX, ECX, EDX, ESI, EDI, EBX, EBP, ESP]> {
 
 def RFP : RegisterClass<f80, 32, [FP0, FP1, FP2, FP3, FP4, FP5, FP6]>;
 
-// Floating point stack registers.
-def RST : RegisterClass<f80, 32, [ST0, ST1, ST2, ST3, ST4, ST5, ST6, ST7]>;
+// Floating point stack registers (these are not allocatable by the
+// register allocator - the floating point stackifier is responsible
+// for transforming FPn allocations to STn registers)
+def RST : RegisterClass<f80, 32, [ST0, ST1, ST2, ST3, ST4, ST5, ST6, ST7]> {
+  let Methods = [{
+    iterator allocation_order_end(MachineFunction &MF) const {
+      return begin();
+    }
+  }];
+}