[llvm-commits] [llvm] r155930 - /llvm/trunk/lib/Target/X86/X86RegisterInfo.cpp

[Preston Gurd]

Author: pgurd
Date: Tue May  1 14:50:22 2012
New Revision: 155930

URL: http://llvm.org/viewvc/llvm-project?rev=155930&view=rev
Log:

This patch marks the X86 floating point stack registers ST0-ST7 as reserved
in order to avoid assertion failures in the register scavenger. The assertion
failures were “Bad machine code: Using an undefined physical register” and
“Bad machine code: MBB exits via unconditional fall-through but its successor
differs from its CFG successor!”.


Modified:
    llvm/trunk/lib/Target/X86/X86RegisterInfo.cpp

Modified: llvm/trunk/lib/Target/X86/X86RegisterInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86RegisterInfo.cpp?rev=155930&r1=155929&r2=155930&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86RegisterInfo.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86RegisterInfo.cpp Tue May  1 14:50:22 2012
@@ -299,6 +299,16 @@
   Reserved.set(X86::FS);
   Reserved.set(X86::GS);
 
+  // Mark the floating point stack registers as reserved.
+  Reserved.set(X86::ST0);
+  Reserved.set(X86::ST1);
+  Reserved.set(X86::ST2);
+  Reserved.set(X86::ST3);
+  Reserved.set(X86::ST4);
+  Reserved.set(X86::ST5);
+  Reserved.set(X86::ST6);
+  Reserved.set(X86::ST7);
+
   // Reserve the registers that only exist in 64-bit mode.
   if (!Is64Bit) {
     // These 8-bit registers are part of the x86-64 extension even though their