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1; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 42; RUN: llc < %s | FileCheck %s3 4; Check that the shr(shl X, 56), 48) is not mistakenly turned into5; a shr (X, -8) that gets subsequently "optimized away" as undef6; PR42547 8; after fixing PR243739; shlq $56, %rdi10; sarq $48, %rdi11; folds into12; movsbq %dil, %rax13; shlq $8, %rax14; which is better for x8615 16target 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-f80:128:128"17target triple = "x86_64-unknown-linux-gnu"18 19define i64 @foo(i64 %b) nounwind readnone {20; CHECK-LABEL: foo:21; CHECK: # %bb.0: # %entry22; CHECK-NEXT: movsbq %dil, %rax23; CHECK-NEXT: shlq $8, %rax24; CHECK-NEXT: incq %rax25; CHECK-NEXT: retq26entry:27 %shl = shl i64 %b, 56 ; <i64> [#uses=1]28 %shr = ashr i64 %shl, 48 ; <i64> [#uses=1]29 %add5 = or i64 %shr, 1 ; <i64> [#uses=1]30 ret i64 %add531}32