[llvm-commits] [llvm] r95259 - in /llvm/trunk: lib/Target/X86/X86ISelLowering.cpp test/CodeGen/X86/tailcall2.ll

[Evan Cheng]

Author: evancheng
Date: Wed Feb  3 15:40:40 2010
New Revision: 95259

URL: http://llvm.org/viewvc/llvm-project?rev=95259&view=rev
Log:
Speculatively disable x86 automatic tail call optimization while we track down a self-hosting issue.

Modified:
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
    llvm/trunk/test/CodeGen/X86/tailcall2.ll

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=95259&r1=95258&r2=95259&view=diff

==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Wed Feb  3 15:40:40 2010
@@ -52,6 +52,7 @@
 
 STATISTIC(NumTailCalls, "Number of tail calls");
 
+static cl::opt<unsigned> TailCallLimit("tailcall-limit", cl::init(0));
 static cl::opt<bool>
 DisableMMX("disable-mmx", cl::Hidden, cl::desc("Disable use of MMX"));
 
@@ -2271,6 +2272,8 @@
 
   // Look for obvious safe cases to perform tail call optimization that does not
   // requite ABI changes. This is what gcc calls sibcall.
+  if (NumTailCalls >= TailCallLimit)
+    return false;
 
   // Do not tail call optimize vararg calls for now.
   if (isVarArg)

Modified: llvm/trunk/test/CodeGen/X86/tailcall2.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/tailcall2.ll?rev=95259&r1=95258&r2=95259&view=diff

==============================================================================
--- llvm/trunk/test/CodeGen/X86/tailcall2.ll (original)
+++ llvm/trunk/test/CodeGen/X86/tailcall2.ll Wed Feb  3 15:40:40 2010
@@ -1,5 +1,6 @@
 ; RUN: llc < %s -march=x86    -asm-verbose=false | FileCheck %s -check-prefix=32
 ; RUN: llc < %s -march=x86-64 -asm-verbose=false | FileCheck %s -check-prefix=64
+; XFAIL: *
 
 define void @t1(i32 %x) nounwind ssp {
 entry: