From: Chris Lattner <sabre@nondot.org>
Date: Wed, 28 Nov 2007 21:26:17 +0000 (+0000)
Subject: Work around a GCC bug, producing this code:
X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=commitdiff_plain;h=4045e6db8c74f71cfbaa6a3681527423679e76ff

Work around a GCC bug, producing this code:

  unsigned char *llvm_cbe_X;
...
  llvm_cbe_X = 0; *((void**)&llvm_cbe_X) = __builtin_stack_save();

instead of:

  llvm_cbe_X = __builtin_stack_save();

See PR1809 for details.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44415 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/CBackend/CBackend.cpp b/lib/Target/CBackend/CBackend.cpp
index 852e28df874..2d18468215e 100644
--- a/lib/Target/CBackend/CBackend.cpp
+++ b/lib/Target/CBackend/CBackend.cpp
@@ -2573,6 +2573,12 @@ void CWriter::visitCallInst(CallInst &I) {
         writeOperand(I.getOperand(3));
         Out << ")";
         return;
+      case Intrinsic::stacksave:
+        // Emit this as: Val = 0; *((void**)&Val) = __builtin_stack_save()
+        // to work around GCC bugs (see PR1809).
+        Out << "0; *((void**)&" << GetValueName(&I)
+            << ") = __builtin_stack_save()";
+        return;
       case Intrinsic::dbg_stoppoint: {
         // If we use writeOperand directly we get a "u" suffix which is rejected
         // by gcc.