[llvm] r176830 - Fix a crasher newly introduced in r176659/r176649, where fast-isel tries to

[Nick Lewycky]

Author: nicholas
Date: Mon Mar 11 16:44:37 2013
New Revision: 176830

URL: http://llvm.org/viewvc/llvm-project?rev=176830&view=rev
Log:
Fix a crasher newly introduced in r176659/r176649, where fast-isel tries to
lower an expect intrinsic that is a constant expression.

Added:
    llvm/trunk/test/CodeGen/X86/fast-isel-expect.ll
Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/FastISel.cpp

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/FastISel.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/FastISel.cpp?rev=176830&r1=176829&r2=176830&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/FastISel.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/FastISel.cpp Mon Mar 11 16:44:37 2013
@@ -698,6 +698,8 @@ bool FastISel::SelectCall(const User *I)
   }
   case Intrinsic::expect: {
     unsigned ResultReg = getRegForValue(Call->getArgOperand(0));
+    if (ResultReg == 0)
+      return false;
     UpdateValueMap(Call, ResultReg);
     return true;
   }

Added: llvm/trunk/test/CodeGen/X86/fast-isel-expect.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/fast-isel-expect.ll?rev=176830&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/X86/fast-isel-expect.ll (added)
+++ llvm/trunk/test/CodeGen/X86/fast-isel-expect.ll Mon Mar 11 16:44:37 2013
@@ -0,0 +1,23 @@
+; RUN: llc < %s -O0 -march=x86 | FileCheck %s
+
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+ at glbl = extern_weak constant i8
+
+declare i64 @llvm.expect.i64(i64, i64) #0
+
+define void @test() {
+; CHECK: movl $glbl
+  %tmp = call i64 @llvm.expect.i64(i64 zext (i1 icmp eq (i8* @glbl, i8* null) to i64), i64 0)
+  %tmp2 = icmp ne i64 %tmp, 0
+  br i1 %tmp2, label %bb1, label %bb2
+
+bb1:
+  unreachable
+
+bb2:
+  unreachable
+}
+
+attributes #0 = { nounwind readnone }