From: Chris Lattner <sabre@nondot.org>
Date: Tue, 27 Sep 2005 22:18:25 +0000 (+0000)
Subject: Darwin, like many BSD systems, has a setjmp/longjmp which saves the signal mask
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=d145a61f8f581cfe7dc7abb023a3b1ab534606c7;p=oota-llvm.git

Darwin, like many BSD systems, has a setjmp/longjmp which saves the signal mask
on setjmp calls and restores it on longjmp calls (both of which require syscalls).

This makes the calls REALLY slow.  Use _setjmp/_longjmp instead.  This speeds up
hexxagon from 120.31s to 15.68s: from 5.53x slower than GCC to 28% faster than GCC.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23482 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/PowerPC/PPCISelLowering.cpp b/lib/Target/PowerPC/PPCISelLowering.cpp
index a6831b024f6..f3b7f64f191 100644
--- a/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -28,6 +28,9 @@ PPC32TargetLowering::PPC32TargetLowering(TargetMachine &TM)
   // Fold away setcc operations if possible.
   setSetCCIsExpensive();
   
+  // Use _setjmp/_longjmp instead of setjmp/longjmp.
+  setUseUnderscoreSetJmpLongJmp(true);
+    
   // Set up the register classes.
   addRegisterClass(MVT::i32, PPC32::GPRCRegisterClass);
   addRegisterClass(MVT::f32, PPC32::FPRCRegisterClass);