llvm/test/CodeGen/SystemZ/int-const-05.ll
Richard Sandiford 65ddcfa8c1 [SystemZ] Prefer LHI;ST... over LAY;MV...
If we had a store of an integer to memory, and the integer and store size
were suitable for a form of MV..., we used MV... no matter what.  We could
then have sequences like:

    lay %r2, 0(%r3,%r4)
    mvi 0(%r2), 4

In these cases it seems better to force the constant into a register
and use a normal store:

    lhi %r2, 4
    stc %r2, 0(%r3, %r4)

since %r2 is more likely to be hoisted and is easier to rematerialize.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189098 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-23 11:18:53 +00:00

102 lines
2.1 KiB
LLVM

; Test moves of integers to 4-byte memory locations.
;
; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s
; Check moves of zero.
define void @f1(i32 *%a) {
; CHECK-LABEL: f1:
; CHECK: mvhi 0(%r2), 0
; CHECK: br %r14
store i32 0, i32 *%a
ret void
}
; Check the high end of the signed 16-bit range.
define void @f2(i32 *%a) {
; CHECK-LABEL: f2:
; CHECK: mvhi 0(%r2), 32767
; CHECK: br %r14
store i32 32767, i32 *%a
ret void
}
; Check the next value up, which can't use MVHI.
define void @f3(i32 *%a) {
; CHECK-LABEL: f3:
; CHECK-NOT: mvhi
; CHECK: br %r14
store i32 32768, i32 *%a
ret void
}
; Check moves of -1.
define void @f4(i32 *%a) {
; CHECK-LABEL: f4:
; CHECK: mvhi 0(%r2), -1
; CHECK: br %r14
store i32 -1, i32 *%a
ret void
}
; Check the low end of the MVHI range.
define void @f5(i32 *%a) {
; CHECK-LABEL: f5:
; CHECK: mvhi 0(%r2), -32768
; CHECK: br %r14
store i32 -32768, i32 *%a
ret void
}
; Check the next value down, which can't use MVHI.
define void @f6(i32 *%a) {
; CHECK-LABEL: f6:
; CHECK-NOT: mvhi
; CHECK: br %r14
store i32 -32769, i32 *%a
ret void
}
; Check the high end of the MVHI range.
define void @f7(i32 *%a) {
; CHECK-LABEL: f7:
; CHECK: mvhi 4092(%r2), 42
; CHECK: br %r14
%ptr = getelementptr i32 *%a, i64 1023
store i32 42, i32 *%ptr
ret void
}
; Check the next word up, which is out of range. We prefer STY in that case.
define void @f8(i32 *%a) {
; CHECK-LABEL: f8:
; CHECK: lhi [[TMP:%r[0-5]]], 42
; CHECK: sty [[TMP]], 4096(%r2)
; CHECK: br %r14
%ptr = getelementptr i32 *%a, i64 1024
store i32 42, i32 *%ptr
ret void
}
; Check negative displacements, for which we again prefer STY.
define void @f9(i32 *%a) {
; CHECK-LABEL: f9:
; CHECK: lhi [[TMP:%r[0-5]]], 42
; CHECK: sty [[TMP]], -4(%r2)
; CHECK: br %r14
%ptr = getelementptr i32 *%a, i64 -1
store i32 42, i32 *%ptr
ret void
}
; Check that MVHI does not allow an index.
define void @f10(i64 %src, i64 %index) {
; CHECK-LABEL: f10:
; CHECK: lhi [[TMP:%r[0-5]]], 42
; CHECK: st [[TMP]], 0({{%r2,%r3|%r3,%r2}})
; CHECK: br %r14
%add = add i64 %src, %index
%ptr = inttoptr i64 %add to i32 *
store i32 42, i32 *%ptr
ret void
}