Files
clang-p2996/llvm/test/CodeGen/AMDGPU/recursion.ll
Matt Arsenault c7a0c2d0f7 AMDGPU: Report large stack usage for recursive calls
We were previously setting an ignored bit in the kernel headers. The
current behavior is to add the large amount on top of the statically
known size of a single stack frame. I'm not sure if we should just use
the large size as the entire reported size instead.
2021-11-10 20:02:01 -05:00

65 lines
1.9 KiB
LLVM

; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 -verify-machineinstrs < %s | FileCheck %s
; CHECK-LABEL: {{^}}recursive:
; CHECK: ScratchSize: 16
define void @recursive() {
call void @recursive()
store volatile i32 0, i32 addrspace(1)* undef
ret void
}
; CHECK-LABEL: {{^}}tail_recursive:
; CHECK: ScratchSize: 0
define void @tail_recursive() {
tail call void @tail_recursive()
ret void
}
define void @calls_tail_recursive() norecurse {
tail call void @tail_recursive()
ret void
}
; CHECK-LABEL: {{^}}tail_recursive_with_stack:
define void @tail_recursive_with_stack() {
%alloca = alloca i32, addrspace(5)
store volatile i32 0, i32 addrspace(5)* %alloca
tail call void @tail_recursive_with_stack()
ret void
}
; For an arbitrary recursive call, report a large number for unknown stack usage.
; CHECK-LABEL: {{^}}calls_recursive:
; CHECK: .amdhsa_private_segment_fixed_size 16400{{$}}
define amdgpu_kernel void @calls_recursive() {
call void @recursive()
ret void
}
; Make sure we do not report a huge stack size for tail recursive
; functions
; CHECK-LABEL: {{^}}kernel_indirectly_calls_tail_recursive:
; CHECK: .amdhsa_private_segment_fixed_size 0{{$}}
define amdgpu_kernel void @kernel_indirectly_calls_tail_recursive() {
call void @calls_tail_recursive()
ret void
}
; TODO: Even though tail_recursive is only called as a tail call, we
; end up treating it as generally recursive call from the regular call
; in the kernel.
; CHECK-LABEL: {{^}}kernel_calls_tail_recursive:
; CHECK: .amdhsa_private_segment_fixed_size 16384{{$}}
define amdgpu_kernel void @kernel_calls_tail_recursive() {
call void @tail_recursive()
ret void
}
; CHECK-LABEL: {{^}}kernel_calls_tail_recursive_with_stack:
; CHECK: .amdhsa_private_segment_fixed_size 16384{{$}}
define amdgpu_kernel void @kernel_calls_tail_recursive_with_stack() {
call void @tail_recursive_with_stack()
ret void
}