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; RUN: llc -verify-machineinstrs < %s -mtriple=aarch64-none-linux-gnu | FileCheck %s --check-prefixes=SDAG,COMMON
; RUN: llc -global-isel -global-isel-abort=1 -verify-machineinstrs < %s -mtriple=aarch64-none-linux-gnu | FileCheck %s --check-prefixes=GISEL,COMMON
declare tailcc void @callee_stack0()
declare tailcc void @callee_stack8([8 x i64], i64)
declare tailcc void @callee_stack16([8 x i64], i64, i64)
declare extern_weak tailcc void @callee_weak()
define tailcc void @caller_to0_from0() nounwind {
; COMMON-LABEL: caller_to0_from0:
; COMMON-NEXT: // %bb.
tail call tailcc void @callee_stack0()
ret void
; COMMON-NEXT: b callee_stack0
}
define tailcc void @caller_to0_from8([8 x i64], i64) #0 {
; COMMON-LABEL: caller_to0_from8:
tail call tailcc void @callee_stack0()
ret void
; COMMON: add sp, sp, #16
; COMMON: .cfi_def_cfa_offset -16
; COMMON-NEXT: b callee_stack0
}
define tailcc void @caller_to8_from0() "frame-pointer"="all" uwtable {
; COMMON-LABEL: caller_to8_from0:
; Key point is that the "42" should go #16 below incoming stack
; pointer (we didn't have arg space to reuse).
tail call tailcc void @callee_stack8([8 x i64] undef, i64 42)
ret void
; COMMON: str {{x[0-9]+}}, [x29, #16]
; COMMON: ldp x29, x30, [sp], #16
; If there is a sub here then the 42 will be briefly exposed to corruption
; from an interrupt if the kernel does not honour a red-zone, and a larger
; call could well overflow the red zone even if it is present.
; COMMON-NOT: sub sp,
; COMMON-NEXT: .cfi_def_cfa_offset 16
; COMMON-NEXT: .cfi_restore w30
; COMMON-NEXT: .cfi_restore w29
; COMMON-NEXT: b callee_stack8
}
define tailcc void @caller_to8_from8([8 x i64], i64 %a) #0 {
; COMMON-LABEL: caller_to8_from8:
; COMMON-NOT: sub sp,
; Key point is that the "%a" should go where at SP on entry.
tail call tailcc void @callee_stack8([8 x i64] undef, i64 42)
ret void
; COMMON: str {{x[0-9]+}}, [sp]
; COMMON-NEXT: b callee_stack8
}
define tailcc void @caller_to16_from8([8 x i64], i64 %a) #0 {
; COMMON-LABEL: caller_to16_from8:
; COMMON-NOT: sub sp,
; Important point is that the call reuses the "dead" argument space
; above %a on the stack. If it tries to go below incoming-SP then the
; callee will not deallocate the space, even in tailcc.
tail call tailcc void @callee_stack16([8 x i64] undef, i64 42, i64 2)
; COMMON: stp {{x[0-9]+}}, {{x[0-9]+}}, [sp]
; COMMON-NEXT: b callee_stack16
ret void
}
define tailcc void @caller_to8_from24([8 x i64], i64 %a, i64 %b, i64 %c) #0 {
; COMMON-LABEL: caller_to8_from24:
; COMMON-NOT: sub sp,
; Key point is that the "%a" should go where at #16 above SP on entry.
tail call tailcc void @callee_stack8([8 x i64] undef, i64 42)
ret void
; COMMON: str {{x[0-9]+}}, [sp, #16]!
; COMMON-NEXT: .cfi_def_cfa_offset -16
; COMMON-NEXT: b callee_stack8
}
define tailcc void @caller_to16_from16([8 x i64], i64 %a, i64 %b) #0 {
; COMMON-LABEL: caller_to16_from16:
; COMMON-NOT: sub sp,
; Here we want to make sure that both loads happen before the stores:
; otherwise either %a or %b will be wrongly clobbered.
tail call tailcc void @callee_stack16([8 x i64] undef, i64 %b, i64 %a)
ret void
; COMMON: ldp {{x[0-9]+}}, {{x[0-9]+}}, [sp]
; COMMON: stp {{x[0-9]+}}, {{x[0-9]+}}, [sp]
; COMMON-NEXT: b callee_stack16
}
define tailcc void @disable_tail_calls() nounwind "disable-tail-calls"="true" {
; COMMON-LABEL: disable_tail_calls:
; COMMON-NEXT: // %bb.
tail call tailcc void @callee_stack0()
ret void
; COMMON: bl callee_stack0
; COMMON: ret
}
; Weakly-referenced extern functions cannot be tail-called, as AAELF does
; not define the behaviour of branch instructions to undefined weak symbols.
define tailcc void @caller_weak() #0 {
; COMMON-LABEL: caller_weak:
; COMMON: bl callee_weak
tail call void @callee_weak()
ret void
}
declare { [2 x float] } @get_vec2()
define { [3 x float] } @test_add_elem() #0 {
; SDAG-LABEL: test_add_elem:
; SDAG: bl get_vec2
; SDAG: fmov s2, #1.0
; SDAG: ret
; GISEL-LABEL: test_add_elem:
; GISEL: str x30, [sp, #-16]!
; GISEL: bl get_vec2
; GISEL: fmov s2, #1.0
; GISEL: ldr x30, [sp], #16
; GISEL: ret
%call = tail call { [2 x float] } @get_vec2()
%arr = extractvalue { [2 x float] } %call, 0
%arr.0 = extractvalue [2 x float] %arr, 0
%arr.1 = extractvalue [2 x float] %arr, 1
%res.0 = insertvalue { [3 x float] } undef, float %arr.0, 0, 0
%res.01 = insertvalue { [3 x float] } %res.0, float %arr.1, 0, 1
%res.012 = insertvalue { [3 x float] } %res.01, float 1.000000e+00, 0, 2
ret { [3 x float] } %res.012
}
declare double @get_double()
define { double, [2 x double] } @test_mismatched_insert() #0 {
; COMMON-LABEL: test_mismatched_insert:
; COMMON: bl get_double
; COMMON: bl get_double
; COMMON: bl get_double
; COMMON: ret
%val0 = call double @get_double()
%val1 = call double @get_double()
%val2 = tail call double @get_double()
%res.0 = insertvalue { double, [2 x double] } undef, double %val0, 0
%res.01 = insertvalue { double, [2 x double] } %res.0, double %val1, 1, 0
%res.012 = insertvalue { double, [2 x double] } %res.01, double %val2, 1, 1
ret { double, [2 x double] } %res.012
}
define void @fromC_totail() #0 {
; COMMON-LABEL: fromC_totail:
; COMMON: sub sp, sp, #32
; COMMON-NOT: sub sp,
; COMMON: mov w[[TMP:[0-9]+]], #42
; COMMON: str x[[TMP]], [sp]
; COMMON: bl callee_stack8
; We must reset the stack to where it was before the call by undoing its extra stack pop.
; COMMON: str x[[TMP]], [sp, #-16]!
; COMMON: bl callee_stack8
; COMMON: sub sp, sp, #16
call tailcc void @callee_stack8([8 x i64] undef, i64 42)
call tailcc void @callee_stack8([8 x i64] undef, i64 42)
ret void
}
define void @fromC_totail_noreservedframe(i32 %len) #0 {
; COMMON-LABEL: fromC_totail_noreservedframe:
; COMMON: stp x29, x30, [sp, #-32]!
; COMMON: mov w[[TMP:[0-9]+]], #42
; Note stack is subtracted here to allocate space for arg
; COMMON: str x[[TMP]], [sp, #-16]!
; COMMON: bl callee_stack8
; And here.
; COMMON: str x[[TMP]], [sp, #-16]!
; COMMON: bl callee_stack8
; But not restored here because callee_stack8 did that for us.
; COMMON-NOT: sub sp,
; Variable sized allocation prevents reserving frame at start of function so each call must allocate any stack space it needs.
%var = alloca i32, i32 %len
call tailcc void @callee_stack8([8 x i64] undef, i64 42)
call tailcc void @callee_stack8([8 x i64] undef, i64 42)
ret void
}
declare void @Ccallee_stack8([8 x i64], i64)
define tailcc void @fromtail_toC() #0 {
; COMMON-LABEL: fromtail_toC:
; COMMON: sub sp, sp, #32
; COMMON-NOT: sub sp,
; COMMON: mov w[[TMP:[0-9]+]], #42
; COMMON: str x[[TMP]], [sp]
; COMMON: bl Ccallee_stack8
; C callees will return with the stack exactly where we left it, so we mustn't try to fix anything.
; COMMON-NOT: add sp,
; COMMON-NOT: sub sp,
; COMMON: str x[[TMP]], [sp]{{$}}
; COMMON: bl Ccallee_stack8
; COMMON-NOT: sub sp,
call void @Ccallee_stack8([8 x i64] undef, i64 42)
call void @Ccallee_stack8([8 x i64] undef, i64 42)
ret void
}
attributes #0 = { uwtable }
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