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; RUN: llc < %s -mtriple=x86_64-pc-win32-coreclr | FileCheck %s -check-prefix=WIN_X64
; RUN: llc < %s -mtriple=x86_64-pc-linux | FileCheck %s -check-prefix=LINUX
; By default, windows CoreCLR requires an inline prologue stack expansion check
; if more than 4096 bytes are allocated on the stack.
; Prolog stack allocation >= 4096 bytes will require the probe sequence
define i32 @main4k() nounwind {
entry:
; WIN_X64-LABEL:main4k:
; WIN_X64: # %bb.0:
; WIN_X64: movl $4096, %eax
; WIN_X64: movq %rcx, 8(%rsp)
; WIN_X64: movq %rdx, 16(%rsp)
; WIN_X64: xorq %rcx, %rcx
; WIN_X64: movq %rsp, %rdx
; WIN_X64: subq %rax, %rdx
; WIN_X64: cmovbq %rcx, %rdx
; WIN_X64: movq %gs:16, %rcx
; WIN_X64: cmpq %rcx, %rdx
; WIN_X64: jae .LBB0_3
; WIN_X64:# %bb.1:
; WIN_X64: andq $-4096, %rdx
; WIN_X64:.LBB0_2:
; WIN_X64: leaq -4096(%rcx), %rcx
; WIN_X64: movb $0, (%rcx)
; WIN_X64: cmpq %rcx, %rdx
; WIN_X64: jne .LBB0_2
; WIN_X64:.LBB0_3:
; WIN_X64: movq 8(%rsp), %rcx
; WIN_X64: movq 16(%rsp), %rdx
; WIN_X64: subq %rax, %rsp
; WIN_X64: xorl %eax, %eax
; WIN_X64: addq $4096, %rsp
; WIN_X64: retq
; LINUX-LABEL:main4k:
; LINUX-NOT: movq %gs:16, %rcx
; LINUX: retq
%a = alloca [4096 x i8]
ret i32 0
}
; Prolog stack allocation >= 4096 bytes will require the probe sequence
; Case with frame pointer
define i32 @main4k_frame() nounwind "no-frame-pointer-elim"="true" {
entry:
; WIN_X64-LABEL:main4k_frame:
; WIN_X64: movq %rcx, 16(%rsp)
; WIN_X64: movq %gs:16, %rcx
; LINUX-LABEL:main4k_frame:
; LINUX-NOT: movq %gs:16, %rcx
; LINUX: retq
%a = alloca [4096 x i8]
ret i32 0
}
; Prolog stack allocation >= 4096 bytes will require the probe sequence
; Case with INT args
define i32 @main4k_intargs(i32 %x, i32 %y) nounwind {
entry:
; WIN_X64: movq %rcx, 8(%rsp)
; WIN_X64: movq %gs:16, %rcx
; LINUX-NOT: movq %gs:16, %rcx
; LINUX: retq
%a = alloca [4096 x i8]
%t = add i32 %x, %y
ret i32 %t
}
; Prolog stack allocation >= 4096 bytes will require the probe sequence
; Case with FP regs
define i32 @main4k_fpargs(double %x, double %y) nounwind {
entry:
; WIN_X64: movq %rcx, 8(%rsp)
; WIN_X64: movq %gs:16, %rcx
; LINUX-NOT: movq %gs:16, %rcx
; LINUX: retq
%a = alloca [4096 x i8]
ret i32 0
}
; Prolog stack allocation >= 4096 bytes will require the probe sequence
; Case with mixed regs
define i32 @main4k_mixargs(double %x, i32 %y) nounwind {
entry:
; WIN_X64: movq %gs:16, %rcx
; LINUX-NOT: movq %gs:16, %rcx
; LINUX: retq
%a = alloca [4096 x i8]
ret i32 %y
}
; Make sure we don't emit the probe for a smaller prolog stack allocation.
define i32 @main128() nounwind {
entry:
; WIN_X64-NOT: movq %gs:16, %rcx
; WIN_X64: retq
; LINUX-NOT: movq %gs:16, %rcx
; LINUX: retq
%a = alloca [128 x i8]
ret i32 0
}
; Make sure we don't emit the probe sequence if not on windows even if the
; caller has the Win64 calling convention.
define win64cc i32 @main4k_win64() nounwind {
entry:
; WIN_X64: movq %gs:16, %rcx
; LINUX-NOT: movq %gs:16, %rcx
; LINUX: retq
%a = alloca [4096 x i8]
ret i32 0
}
declare i32 @bar(i8*) nounwind
; Within-body inline probe expansion
define win64cc i32 @main4k_alloca(i64 %n) nounwind {
entry:
; WIN_X64: callq bar
; WIN_X64: movq %gs:16, [[R:%r.*]]
; WIN_X64: callq bar
; LINUX: callq bar
; LINUX-NOT: movq %gs:16, [[R:%r.*]]
; LINUX: callq bar
%a = alloca i8, i64 1024
%ra = call i32 @bar(i8* %a) nounwind
%b = alloca i8, i64 %n
%rb = call i32 @bar(i8* %b) nounwind
%r = add i32 %ra, %rb
ret i32 %r
}
; Influence of stack-probe-size attribute
; Note this is not exposed in coreclr
define i32 @test_probe_size() "stack-probe-size"="8192" nounwind {
; WIN_X64-NOT: movq %gs:16, %rcx
; WIN_X64: retq
; LINUX-NOT: movq %gs:16, %rcx
; LINUX: retq
%a = alloca [4096 x i8]
ret i32 0
}
|
