Compiler projects using llvm
# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
# RUN: llc -mtriple=aarch64-- -run-pass=instruction-select -verify-machineinstrs %s -o - | FileCheck %s
--- |
  target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
  target triple = "aarch64"

  @x = dso_local global i32 -32768, align 4

  define dso_local i32 @check_sext_not_lost(i32* %ptr) {
  entry:
    %ptr.addr = alloca i32*, align 8
    store i32* %ptr, i32** %ptr.addr, align 8
    %0 = load i32*, i32** %ptr.addr, align 8
    %1 = load i32, i32* @x, align 4
    %sub = sub nsw i32 %1, 32768
    %conv = trunc i32 %sub to i16
    %idxprom = sext i16 %conv to i64
    %arrayidx = getelementptr inbounds i32, i32* %0, i64 %idxprom
    %2 = load i32, i32* %arrayidx, align 4
    ret i32 %2
  }

...
---
name:            check_sext_not_lost
alignment:       4
legalized:       true
regBankSelected: true
tracksRegLiveness: true
registers:
  - { id: 0, class: gpr }
  - { id: 1, class: gpr }
  - { id: 2, class: gpr }
  - { id: 3, class: gpr }
  - { id: 4, class: gpr }
  - { id: 5, class: gpr }
  - { id: 6, class: gpr }
  - { id: 7, class: _ }
  - { id: 8, class: gpr }
  - { id: 9, class: _ }
  - { id: 10, class: gpr }
  - { id: 11, class: gpr }
  - { id: 12, class: _ }
  - { id: 13, class: gpr }
  - { id: 14, class: gpr }
  - { id: 15, class: gpr64 }
  - { id: 16, class: gpr }
liveins:
  - { reg: '$x0' }
frameInfo:
  maxAlignment:    8
  maxCallFrameSize: 0
stack:
  - { id: 0, name: ptr.addr, size: 8, alignment: 8 }
machineFunctionInfo: {}
body:             |
  bb.0.entry:
    liveins: $x0

    ; CHECK-LABEL: name: check_sext_not_lost
    ; CHECK: liveins: $x0
    ; CHECK: [[COPY:%[0-9]+]]:gpr64all = COPY $x0
    ; CHECK: [[COPY1:%[0-9]+]]:gpr64 = COPY [[COPY]]
    ; CHECK: STRXui [[COPY1]], %stack.0.ptr.addr, 0 :: (store (p0) into %ir.ptr.addr)
    ; CHECK: [[LDRXui:%[0-9]+]]:gpr64common = LDRXui %stack.0.ptr.addr, 0 :: (dereferenceable load (p0) from %ir.ptr.addr)
    ; CHECK: [[ADRP:%[0-9]+]]:gpr64common = ADRP target-flags(aarch64-page) @x
    ; CHECK: [[LDRWui:%[0-9]+]]:gpr32common = LDRWui [[ADRP]], target-flags(aarch64-pageoff, aarch64-nc) @x :: (dereferenceable load (s32) from @x)
    ; CHECK: [[SUBSWri:%[0-9]+]]:gpr32 = nsw SUBSWri [[LDRWui]], 8, 12, implicit-def $nzcv
    ; CHECK: [[DEF:%[0-9]+]]:gpr64all = IMPLICIT_DEF
    ; CHECK: [[INSERT_SUBREG:%[0-9]+]]:gpr64 = INSERT_SUBREG [[DEF]], [[SUBSWri]], %subreg.sub_32
    ; CHECK: [[SBFMXri:%[0-9]+]]:gpr64 = SBFMXri [[INSERT_SUBREG]], 0, 15
    ; CHECK: [[LDRWroX:%[0-9]+]]:gpr32 = LDRWroX [[LDRXui]], [[SBFMXri]], 0, 1 :: (load (s32) from %ir.arrayidx)
    ; CHECK: $w0 = COPY [[LDRWroX]]
    ; CHECK: RET_ReallyLR implicit $w0
    %0:gpr(p0) = COPY $x0
    %1:gpr(p0) = G_FRAME_INDEX %stack.0.ptr.addr
    G_STORE %0(p0), %1(p0) :: (store (p0) into %ir.ptr.addr)
    %2:gpr(p0) = G_LOAD %1(p0) :: (dereferenceable load (p0) from %ir.ptr.addr)
    %15:gpr64(p0) = ADRP target-flags(aarch64-page) @x
    %4:gpr(p0) = G_ADD_LOW %15(p0), target-flags(aarch64-pageoff, aarch64-nc) @x
    %3:gpr(s32) = G_LOAD %4(p0) :: (dereferenceable load (s32) from @x)
    %5:gpr(s32) = G_CONSTANT i32 32768
    %6:gpr(s32) = nsw G_SUB %3, %5
    %16:gpr(s64) = G_ANYEXT %6(s32)
    %8:gpr(s64) = G_SEXT_INREG %16, 16
    %14:gpr(s64) = G_CONSTANT i64 2
    %10:gpr(s64) = G_SHL %8, %14(s64)
    %11:gpr(p0) = G_PTR_ADD %2, %10(s64)
    %13:gpr(s32) = G_LOAD %11(p0) :: (load (s32) from %ir.arrayidx)
    $w0 = COPY %13(s32)
    RET_ReallyLR implicit $w0

...