test/CodeGen/RISCV/rv64i-shift-sext.ll

; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc -mtriple=riscv64 -verify-machineinstrs < %s \
; RUN:   | FileCheck %s -check-prefix=RV64I

; Test that we turn (sra (shl X, 32), 32-C) into (slli (sext.w X), C)

define i64 @test1(i64 %a) nounwind {
; RV64I-LABEL: test1:
; RV64I:       # %bb.0:
; RV64I-NEXT:    sext.w a0, a0
; RV64I-NEXT:    slli a0, a0, 2
; RV64I-NEXT:    ret
  %1 = shl i64 %a, 32
  %2 = ashr i64 %1, 30
  ret i64 %2
}

define i64 @test2(i32 signext %a) nounwind {
; RV64I-LABEL: test2:
; RV64I:       # %bb.0:
; RV64I-NEXT:    slli a0, a0, 3
; RV64I-NEXT:    ret
  %1 = zext i32 %a to i64
  %2 = shl i64 %1, 32
  %3 = ashr i64 %2, 29
  ret i64 %3
}

define i64 @test3(i32* %a) nounwind {
; RV64I-LABEL: test3:
; RV64I:       # %bb.0:
; RV64I-NEXT:    lw a0, 0(a0)
; RV64I-NEXT:    slli a0, a0, 4
; RV64I-NEXT:    ret
  %1 = load i32, i32* %a
  %2 = zext i32 %1 to i64
  %3 = shl i64 %2, 32
  %4 = ashr i64 %3, 28
  ret i64 %4
}

define i64 @test4(i32 signext %a, i32 signext %b) nounwind {
; RV64I-LABEL: test4:
; RV64I:       # %bb.0:
; RV64I-NEXT:    addw a0, a0, a1
; RV64I-NEXT:    slli a0, a0, 30
; RV64I-NEXT:    ret
  %1 = add i32 %a, %b
  %2 = zext i32 %1 to i64
  %3 = shl i64 %2, 32
  %4 = ashr i64 %3, 2
  ret i64 %4
}

define i64 @test5(i32 signext %a, i32 signext %b) nounwind {
; RV64I-LABEL: test5:
; RV64I:       # %bb.0:
; RV64I-NEXT:    xor a0, a0, a1
; RV64I-NEXT:    slli a0, a0, 31
; RV64I-NEXT:    ret
  %1 = xor i32 %a, %b
  %2 = zext i32 %1 to i64
  %3 = shl i64 %2, 32
  %4 = ashr i64 %3, 1
  ret i64 %4
}

define i64 @test6(i32 signext %a, i32 signext %b) nounwind {
; RV64I-LABEL: test6:
; RV64I:       # %bb.0:
; RV64I-NEXT:    sllw a0, a0, a1
; RV64I-NEXT:    slli a0, a0, 16
; RV64I-NEXT:    ret
  %1 = shl i32 %a, %b
  %2 = zext i32 %1 to i64
  %3 = shl i64 %2, 32
  %4 = ashr i64 %3, 16
  ret i64 %4
}

; The ashr+add+shl is canonical IR from InstCombine for
; (sext (add (trunc X to i32), 1) to i32).
; That can be implemented as addiw make sure we recover it.
define i64 @test7(i32* %0, i64 %1) {
; RV64I-LABEL: test7:
; RV64I:       # %bb.0:
; RV64I-NEXT:    addiw a0, a1, 1
; RV64I-NEXT:    ret
  %3 = shl i64 %1, 32
  %4 = add i64 %3, 4294967296
  %5 = ashr exact i64 %4, 32
  ret i64 %5
}

; The ashr+add+shl is canonical IR from InstCombine for
; (sext (sub 1, (trunc X to i32)) to i32).
; That can be implemented as (li 1)+subw make sure we recover it.
define i64 @test8(i32* %0, i64 %1) {
; RV64I-LABEL: test8:
; RV64I:       # %bb.0:
; RV64I-NEXT:    li a0, 1
; RV64I-NEXT:    subw a0, a0, a1
; RV64I-NEXT:    ret
  %3 = mul i64 %1, -4294967296
  %4 = add i64 %3, 4294967296
  %5 = ashr exact i64 %4, 32
  ret i64 %5
}

; The gep is here to introduce a shl by 2 after the ashr that will get folded
; and make this harder to recover.
define signext i32 @test9(i32* %0, i64 %1) {
; RV64I-LABEL: test9:
; RV64I:       # %bb.0:
; RV64I-NEXT:    lui a2, 1
; RV64I-NEXT:    addiw a2, a2, 1
; RV64I-NEXT:    addw a1, a1, a2
; RV64I-NEXT:    slli a1, a1, 2
; RV64I-NEXT:    add a0, a0, a1
; RV64I-NEXT:    lw a0, 0(a0)
; RV64I-NEXT:    ret
  %3 = shl i64 %1, 32
  %4 = add i64 %3, 17596481011712 ; 4097 << 32
  %5 = ashr exact i64 %4, 32
  %6 = getelementptr inbounds i32, i32* %0, i64 %5
  %7 = load i32, i32* %6, align 4
  ret i32 %7
}

; The gep is here to introduce a shl by 2 after the ashr that will get folded
; and make this harder to recover.
define signext i32 @test10(i32* %0, i64 %1) {
; RV64I-LABEL: test10:
; RV64I:       # %bb.0:
; RV64I-NEXT:    lui a2, 30141
; RV64I-NEXT:    addiw a2, a2, -747
; RV64I-NEXT:    subw a1, a2, a1
; RV64I-NEXT:    slli a1, a1, 2
; RV64I-NEXT:    add a0, a0, a1
; RV64I-NEXT:    lw a0, 0(a0)
; RV64I-NEXT:    ret
  %3 = mul i64 %1, -4294967296
  %4 = add i64 %3, 530242871224172544 ; 123456789 << 32
  %5 = ashr exact i64 %4, 32
  %6 = getelementptr inbounds i32, i32* %0, i64 %5
  %7 = load i32, i32* %6, align 4
  ret i32 %7
}

define i64 @test11(i32* %0, i64 %1) {
; RV64I-LABEL: test11:
; RV64I:       # %bb.0:
; RV64I-NEXT:    lui a0, 524288
; RV64I-NEXT:    subw a0, a0, a1
; RV64I-NEXT:    ret
  %3 = mul i64 %1, -4294967296
  %4 = add i64 %3, 9223372036854775808 ;0x8000'0000'0000'0000
  %5 = ashr exact i64 %4, 32
  ret i64 %5
}

; Make sure we use slli+srai to enable the possibility of compressed
define i32 @test12(i32 signext %0) {
; RV64I-LABEL: test12:
; RV64I:       # %bb.0:
; RV64I-NEXT:    slli a0, a0, 49
; RV64I-NEXT:    srai a0, a0, 47
; RV64I-NEXT:    ret
  %2 = shl i32 %0, 17
  %3 = ashr i32 %2, 15
  ret i32 %3
}

define i8 @test13(i8* %0, i64 %1) {
; RV64I-LABEL: test13:
; RV64I:       # %bb.0:
; RV64I-NEXT:    li a2, 1
; RV64I-NEXT:    subw a2, a2, a1
; RV64I-NEXT:    add a2, a0, a2
; RV64I-NEXT:    lb a2, 0(a2)
; RV64I-NEXT:    li a3, 2
; RV64I-NEXT:    subw a1, a3, a1
; RV64I-NEXT:    add a0, a0, a1
; RV64I-NEXT:    lb a0, 0(a0)
; RV64I-NEXT:    add a0, a2, a0
; RV64I-NEXT:    ret
  %3 = mul i64 %1, -4294967296
  %4 = add i64 %3, 4294967296 ; 1 << 32
  %5 = ashr exact i64 %4, 32
  %6 = getelementptr inbounds i8, i8* %0, i64 %5
  %7 = load i8, i8* %6, align 4
  %8 = add i64 %3, 8589934592 ; 2 << 32
  %9 = ashr exact i64 %8, 32
  %10 = getelementptr inbounds i8, i8* %0, i64 %9
  %11 = load i8, i8* %10, align 4
  %12 = add i8 %7, %11
  ret i8 %12
}