X86 Lowering - Fixed a crash in ICMP scalar instruction

Fixed a bug in EmitTest() function in combining shl + icmp.

https://llvm.org/bugs/show_bug.cgi?id=28119

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273899 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index ebd7fa619f7f931e48288b3e74f932eebd9419b4..3c4ef2bc526cc98cbcc9ef021977ec0175b58e9f 100644 (file)
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -14597,10 +14597,8 @@ SDValue X86TargetLowering::EmitTest(SDValue Op, unsigned X86CC, const SDLoc &dl,
                        : APInt::getLowBitsSet(BitWidth, BitWidth - ShAmt);
       if (!Mask.isSignedIntN(32)) // Avoid large immediates.
         break;
-      SDValue New = DAG.getNode(ISD::AND, dl, VT, Op->getOperand(0),
-                                DAG.getConstant(Mask, dl, VT));
-      DAG.ReplaceAllUsesWith(Op, New);
-      Op = New;
+      Op = DAG.getNode(ISD::AND, dl, VT, Op->getOperand(0),
+                       DAG.getConstant(Mask, dl, VT));
     }
     break;
 

diff --git a/test/CodeGen/X86/2016-06-28-ICmpCrash.ll b/test/CodeGen/X86/2016-06-28-ICmpCrash.ll
new file mode 100644 (file)
index 0000000..f5a8d96
--- /dev/null
+++ b/test/CodeGen/X86/2016-06-28-ICmpCrash.ll
@@ -0,0 +1,31 @@
+;RUN: llc < %s -mcpu=core-avx2
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+%struct.struct_1 = type { i24 }
+
+@a = global i8 0, align 1
+@b = global i8 0, align 1
+@d = global i8 0, align 1
+@e = global i8 0, align 1
+@c = global %struct.struct_1 zeroinitializer, align 4
+
+; Function Attrs: norecurse nounwind uwtable
+define void @_Z3fn1v() #0 {
+  %bf.load = load i32, i32* bitcast (%struct.struct_1* @c to i32*), align 4
+  %bf.shl = shl i32 %bf.load, 8
+  %bf.ashr = ashr exact i32 %bf.shl, 8
+  %tobool4 = icmp ne i32 %bf.ashr, 0
+  %conv = zext i1 %tobool4 to i32
+  %x1 = load i8, i8* @e, align 1
+  %conv6 = zext i8 %x1 to i32
+  %add = add nuw nsw i32 %conv, %conv6
+  %tobool7 = icmp ne i32 %add, 0
+  %frombool = zext i1 %tobool7 to i8
+  store i8 %frombool, i8* @b, align 1
+  %tobool14 = icmp ne i32 %bf.shl, 0
+  %frombool15 = zext i1 %tobool14 to i8
+  store i8 %frombool15, i8* @d, align 1
+  ret void
+}
\ No newline at end of file