Index: lib/CodeGen/SelectionDAG/DAGCombiner.cpp =================================================================== --- lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -3850,7 +3850,6 @@ return false; } case ISD::ZERO_EXTEND: - case ISD::ANY_EXTEND: case ISD::AssertZext: { unsigned ActiveBits = Mask->getAPIntValue().countTrailingOnes(); EVT ExtVT = EVT::getIntegerVT(*DAG.getContext(), ActiveBits); Index: test/CodeGen/X86/pr35765.ll =================================================================== --- /dev/null +++ test/CodeGen/X86/pr35765.ll @@ -0,0 +1,42 @@ +; RUN: llc -mtriple=x86_64-unknown-linux-gnu %s -o - | FileCheck %s + +@ll = local_unnamed_addr global i64 0, align 8 +@x = local_unnamed_addr global i64 2651237805702985558, align 8 +@s1 = local_unnamed_addr global { i8, i8 } { i8 123, i8 5 }, align 2 +@s2 = local_unnamed_addr global { i8, i8 } { i8 -122, i8 3 }, align 2 + +; CHECK-LABEL: PR35765 +; CHECK: movzwl s1(%rip), %ecx +; CHECK: addl $-1398, %ecx +; CHECK: movl $4, %eax +; CHECK: shll %cl, %eax +; CHECK: movzwl x(%rip), %ecx +; CHECK: movzwl s2(%rip), %edx +; CHECK: notl %edx +; CHECK: orl $63488, %edx +; CHECK: movzwl %dx, %edx +; CHECK: orl %ecx, %edx +; CHECK: xorl %eax, %edx +; CHECK: movslq %edx, %rax +; CHECK: movq %rax, ll(%rip) +; CHECK: retq +define void @PR35765() { +entry: + %bf.load.i = load i16, i16* bitcast ({ i8, i8 }* @s1 to i16*), align 2 + %bf.clear.i = and i16 %bf.load.i, 2047 + %conv.i = zext i16 %bf.clear.i to i32 + %sub.i = add nsw i32 %conv.i, -1398 + %shl.i = shl i32 4, %sub.i + %0 = load i64, i64* @x, align 8 + %bf.load1.i = load i16, i16* bitcast ({ i8, i8 }* @s2 to i16*), align 2 + %bf.clear2.i = and i16 %bf.load1.i, 2047 + %1 = xor i16 %bf.clear2.i, -1 + %neg.i = zext i16 %1 to i64 + %or.i = or i64 %0, %neg.i + %conv5.i = trunc i64 %or.i to i32 + %conv6.i = and i32 %conv5.i, 65535 + %xor.i = xor i32 %conv6.i, %shl.i + %conv7.i = sext i32 %xor.i to i64 + store i64 %conv7.i, i64* @ll, align 8 + ret void +}