test/CodeGen/SystemZ/remat.ll

; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
; Test avoiding the unnecessary spill by marking loads as rematerializable and
; just directly loading from where the argument was originally passed on the
; stack - moving the load down to the remat site.

; RUN: llc < %s -verify-machineinstrs -mtriple=s390x-linux-gnu -O1 | FileCheck %s

define void @remat_load(
; CHECK-LABEL: remat_load:
; CHECK:       # %bb.0: # %entry
; CHECK-NEXT:    stmg %r6, %r15, 48(%r15)
; CHECK-NEXT:    aghi %r15, -64
; CHECK-NEXT:    std %f8, 56(%r15) # 8-byte Spill
; CHECK-NEXT:    std %f9, 48(%r15) # 8-byte Spill
; CHECK-NEXT:    std %f10, 40(%r15) # 8-byte Spill
; CHECK-NEXT:    std %f11, 32(%r15) # 8-byte Spill
; CHECK-NEXT:    std %f12, 24(%r15) # 8-byte Spill
; CHECK-NEXT:    std %f13, 16(%r15) # 8-byte Spill
; CHECK-NEXT:    std %f14, 8(%r15) # 8-byte Spill
; CHECK-NEXT:    std %f15, 0(%r15) # 8-byte Spill
; CHECK-NEXT:    lg %r0, 232(%r15)
; CHECK-NEXT:    lg %r1, 224(%r15)
; CHECK-NEXT:    ld %f0, 280(%r15)
; CHECK-NEXT:    le %f1, 276(%r15)
; CHECK-NEXT:    le %f2, 268(%r15)
; CHECK-NEXT:    lg %r14, 288(%r15)
; CHECK-NEXT:    le %f3, 260(%r15)
; CHECK-NEXT:    l %r3, 244(%r15)
; CHECK-NEXT:    lg %r2, 248(%r15)
; CHECK-NEXT:    stc %r1, 0(%r14)
; CHECK-NEXT:    sth %r0, 0(%r14)
; CHECK-NEXT:    st %r3, 0(%r14)
; CHECK-NEXT:    stg %r2, 0(%r14)
; CHECK-NEXT:    ste %f3, 0(%r14)
; CHECK-NEXT:    ste %f2, 0(%r14)
; CHECK-NEXT:    ste %f1, 0(%r14)
; CHECK-NEXT:    std %f0, 0(%r14)
; CHECK-NEXT:    #APP
; CHECK-NEXT:    #NO_APP
; CHECK-NEXT:    lg %r0, 224(%r15)
; CHECK-NEXT:    stc %r0, 0(%r14)
; CHECK-NEXT:    lg %r0, 232(%r15)
; CHECK-NEXT:    sth %r0, 0(%r14)
; CHECK-NEXT:    l %r0, 244(%r15)
; CHECK-NEXT:    st %r0, 0(%r14)
; CHECK-NEXT:    lg %r0, 248(%r15)
; CHECK-NEXT:    stg %r0, 0(%r14)
; CHECK-NEXT:    le %f0, 260(%r15)
; CHECK-NEXT:    ste %f0, 0(%r14)
; CHECK-NEXT:    le %f0, 268(%r15)
; CHECK-NEXT:    ste %f0, 0(%r14)
; CHECK-NEXT:    le %f0, 276(%r15)
; CHECK-NEXT:    ste %f0, 0(%r14)
; CHECK-NEXT:    ld %f0, 280(%r15)
; CHECK-NEXT:    std %f0, 0(%r14)
; CHECK-NEXT:    ld %f8, 56(%r15) # 8-byte Reload
; CHECK-NEXT:    ld %f9, 48(%r15) # 8-byte Reload
; CHECK-NEXT:    ld %f10, 40(%r15) # 8-byte Reload
; CHECK-NEXT:    ld %f11, 32(%r15) # 8-byte Reload
; CHECK-NEXT:    ld %f12, 24(%r15) # 8-byte Reload
; CHECK-NEXT:    ld %f13, 16(%r15) # 8-byte Reload
; CHECK-NEXT:    ld %f14, 8(%r15) # 8-byte Reload
; CHECK-NEXT:    ld %f15, 0(%r15) # 8-byte Reload
; CHECK-NEXT:    lmg %r6, %r15, 112(%r15)
; CHECK-NEXT:    br %r14
    i64 %i0, i64 %i1, i64 %i2, i64 %i3, i64 %i4, ; r2-r6
    double %f0, double %f1, double %f2, double %f3, ; f0, f2, f4, f6
    i8 signext %stackarg0,
    i16 zeroext %stackarg1,
    i32 %stackarg2,
    i64 %stackarg3,
    float %stackarg4,
    float %stackarg5,
    float %stackarg6,
    double %stackarg7,
    ptr %p
) nounwind {
entry:
  ; Add a use of the stack arguments here so that we will have to load them from
  ; the stack before the inline asm. Otherwise we would be exercising the
  ; machine scheduler, not rematerialization.
  store volatile i8 %stackarg0, ptr %p
  store volatile i16 %stackarg1, ptr %p
  store volatile i32 %stackarg2, ptr %p
  store volatile i64 %stackarg3, ptr %p
  store volatile float %stackarg4, ptr %p
  store volatile float %stackarg5, ptr %p
  store volatile float %stackarg6, ptr %p
  store volatile double %stackarg7, ptr %p
  ; Clobber registers to force re-loads
  tail call void asm sideeffect "", "~{r0},~{r1},~{r2},~{r3},~{r4},~{r5},~{r6},~{r7},~{r8},~{r9},~{r10},~{r11},~{r12},~{r13},~{f0},~{f1},~{f2},~{f3},~{f4},~{f5},~{f6},~{f7},~{f8},~{f9},~{f10},~{f11},~{f12},~{f13},~{f14},~{f15}"()
  ; Now use them after spilling everything to force rematerialization
  store volatile i8 %stackarg0, ptr %p
  store volatile i16 %stackarg1, ptr %p
  store volatile i32 %stackarg2, ptr %p
  store volatile i64 %stackarg3, ptr %p
  store volatile float %stackarg4, ptr %p
  store volatile float %stackarg5, ptr %p
  store volatile float %stackarg6, ptr %p
  store volatile double %stackarg7, ptr %p
  ret void
}

@const = external constant i32
; Remat the load of the constant global.
define i32 @constglobal_load() nounwind {
; CHECK-LABEL: constglobal_load:
; CHECK:       # %bb.0: # %entry
; CHECK-NEXT:    stmg %r6, %r15, 48(%r15)
; CHECK-NEXT:    #APP
; CHECK-NEXT:    #NO_APP
; CHECK-NEXT:    lhi %r2, 1
; CHECK-NEXT:    lgrl %r1, const@GOT
; CHECK-NEXT:    a %r2, 0(%r1)
; CHECK-NEXT:    lmg %r6, %r15, 48(%r15)
; CHECK-NEXT:    br %r14
entry:
  %global = load i32, ptr @const
  tail call void asm sideeffect "", "~{r0},~{r1},~{r2},~{r3},~{r4},~{r5},~{r6},~{r7},~{r8},~{r9},~{r10},~{r11},~{r12},~{r13},~{r14},~{r15}"()
  %a = add i32 %global, 1
  ret i32 %a
}