llvm/test/CodeGen/SystemZ/int-mul-08.ll

; Test high-part i64->i128 multiplications.
;
; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s

; Check zero-extended multiplication in which only the high part is used.
define i64 @f1(i64 %dummy, i64 %a, i64 %b) {
; CHECK: f1:
; CHECK-NOT: {{%r[234]}}
; CHECK: mlgr %r2, %r4
; CHECK: br %r14
  %ax = zext i64 %a to i128
  %bx = zext i64 %b to i128
  %mulx = mul i128 %ax, %bx
  %highx = lshr i128 %mulx, 64
  %high = trunc i128 %highx to i64
  ret i64 %high
}

; Check sign-extended multiplication in which only the high part is used.
; This needs a rather convoluted sequence.
define i64 @f2(i64 %dummy, i64 %a, i64 %b) {
; CHECK: f2:
; CHECK: mlgr
; CHECK: agr
; CHECK: agr
; CHECK: br %r14
  %ax = sext i64 %a to i128
  %bx = sext i64 %b to i128
  %mulx = mul i128 %ax, %bx
  %highx = lshr i128 %mulx, 64
  %high = trunc i128 %highx to i64
  ret i64 %high
}

; Check zero-extended multiplication in which only part of the high half
; is used.
define i64 @f3(i64 %dummy, i64 %a, i64 %b) {
; CHECK: f3:
; CHECK-NOT: {{%r[234]}}
; CHECK: mlgr %r2, %r4
; CHECK: srlg %r2, %r2, 3
; CHECK: br %r14
  %ax = zext i64 %a to i128
  %bx = zext i64 %b to i128
  %mulx = mul i128 %ax, %bx
  %highx = lshr i128 %mulx, 67
  %high = trunc i128 %highx to i64
  ret i64 %high
}

; Check zero-extended multiplication in which the result is split into
; high and low halves.
define i64 @f4(i64 %dummy, i64 %a, i64 %b) {
; CHECK: f4:
; CHECK-NOT: {{%r[234]}}
; CHECK: mlgr %r2, %r4
; CHECK: ogr %r2, %r3
; CHECK: br %r14
  %ax = zext i64 %a to i128
  %bx = zext i64 %b to i128
  %mulx = mul i128 %ax, %bx
  %highx = lshr i128 %mulx, 64
  %high = trunc i128 %highx to i64
  %low = trunc i128 %mulx to i64
  %or = or i64 %high, %low
  ret i64 %or
}

; Check division by a constant, which should use multiplication instead.
define i64 @f5(i64 %dummy, i64 %a) {
; CHECK: f5:
; CHECK: mlgr %r2,
; CHECK: srlg %r2, %r2,
; CHECK: br %r14
  %res = udiv i64 %a, 1234
  ret i64 %res
}

; Check MLG with no displacement.
define i64 @f6(i64 %dummy, i64 %a, i64 *%src) {
; CHECK: f6:
; CHECK-NOT: {{%r[234]}}
; CHECK: mlg %r2, 0(%r4)
; CHECK: br %r14
  %b = load i64 *%src
  %ax = zext i64 %a to i128
  %bx = zext i64 %b to i128
  %mulx = mul i128 %ax, %bx
  %highx = lshr i128 %mulx, 64
  %high = trunc i128 %highx to i64
  ret i64 %high
}

; Check the high end of the aligned MLG range.
define i64 @f7(i64 %dummy, i64 %a, i64 *%src) {
; CHECK: f7:
; CHECK: mlg %r2, 524280(%r4)
; CHECK: br %r14
  %ptr = getelementptr i64 *%src, i64 65535
  %b = load i64 *%ptr
  %ax = zext i64 %a to i128
  %bx = zext i64 %b to i128
  %mulx = mul i128 %ax, %bx
  %highx = lshr i128 %mulx, 64
  %high = trunc i128 %highx to i64
  ret i64 %high
}

; Check the next doubleword up, which requires separate address logic.
; Other sequences besides this one would be OK.
define i64 @f8(i64 %dummy, i64 %a, i64 *%src) {
; CHECK: f8:
; CHECK: agfi %r4, 524288
; CHECK: mlg %r2, 0(%r4)
; CHECK: br %r14
  %ptr = getelementptr i64 *%src, i64 65536
  %b = load i64 *%ptr
  %ax = zext i64 %a to i128
  %bx = zext i64 %b to i128
  %mulx = mul i128 %ax, %bx
  %highx = lshr i128 %mulx, 64
  %high = trunc i128 %highx to i64
  ret i64 %high
}

; Check the high end of the negative aligned MLG range.
define i64 @f9(i64 %dummy, i64 %a, i64 *%src) {
; CHECK: f9:
; CHECK: mlg %r2, -8(%r4)
; CHECK: br %r14
  %ptr = getelementptr i64 *%src, i64 -1
  %b = load i64 *%ptr
  %ax = zext i64 %a to i128
  %bx = zext i64 %b to i128
  %mulx = mul i128 %ax, %bx
  %highx = lshr i128 %mulx, 64
  %high = trunc i128 %highx to i64
  ret i64 %high
}

; Check the low end of the MLG range.
define i64 @f10(i64 %dummy, i64 %a, i64 *%src) {
; CHECK: f10:
; CHECK: mlg %r2, -524288(%r4)
; CHECK: br %r14
  %ptr = getelementptr i64 *%src, i64 -65536
  %b = load i64 *%ptr
  %ax = zext i64 %a to i128
  %bx = zext i64 %b to i128
  %mulx = mul i128 %ax, %bx
  %highx = lshr i128 %mulx, 64
  %high = trunc i128 %highx to i64
  ret i64 %high
}

; Check the next doubleword down, which needs separate address logic.
; Other sequences besides this one would be OK.
define i64 @f11(i64 *%dest, i64 %a, i64 *%src) {
; CHECK: f11:
; CHECK: agfi %r4, -524296
; CHECK: mlg %r2, 0(%r4)
; CHECK: br %r14
  %ptr = getelementptr i64 *%src, i64 -65537
  %b = load i64 *%ptr
  %ax = zext i64 %a to i128
  %bx = zext i64 %b to i128
  %mulx = mul i128 %ax, %bx
  %highx = lshr i128 %mulx, 64
  %high = trunc i128 %highx to i64
  ret i64 %high
}

; Check that MLG allows an index.
define i64 @f12(i64 *%dest, i64 %a, i64 %src, i64 %index) {
; CHECK: f12:
; CHECK: mlg %r2, 524287(%r5,%r4)
; CHECK: br %r14
  %add1 = add i64 %src, %index
  %add2 = add i64 %add1, 524287
  %ptr = inttoptr i64 %add2 to i64 *
  %b = load i64 *%ptr
  %ax = zext i64 %a to i128
  %bx = zext i64 %b to i128
  %mulx = mul i128 %ax, %bx
  %highx = lshr i128 %mulx, 64
  %high = trunc i128 %highx to i64
  ret i64 %high
}