llvm/test/CodeGen/AMDGPU/spill-alloc-sgpr-init-bug.ll
Nicolai Haehnle cb2ad1e249 AMDGPU/SI: Do not move scratch resource register on Tonga & Iceland
Due to the SGPR init bug, every program claims to use the same number
of SGPRs anyway, so there's no point in trying to shift those registers
down from their initial spot of reservation.

Add a test that uses VGPR spilling and blocks most SGPRs from being used for
the scratch resource register. Previously, this would run into an assertion.

Differential Revision: http://reviews.llvm.org/D15724

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256870 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-05 20:42:49 +00:00

25 lines
1.1 KiB
LLVM

; RUN: llc -march=amdgcn -mcpu=tonga < %s | FileCheck --check-prefix=TONGA %s
; On Tonga and Iceland, limited SGPR availability means care must be taken to
; allocate scratch registers correctly. Check that this test compiles without
; error.
; TONGA-LABEL: test
define void @test(<256 x i32> addrspace(1)* %out, <256 x i32> addrspace(1)* %in) {
entry:
%tid = call i32 @llvm.SI.tid() nounwind readnone
%aptr = getelementptr <256 x i32>, <256 x i32> addrspace(1)* %in, i32 %tid
%a = load <256 x i32>, <256 x i32> addrspace(1)* %aptr
call void asm sideeffect "", "~{memory}" ()
%outptr = getelementptr <256 x i32>, <256 x i32> addrspace(1)* %in, i32 %tid
store <256 x i32> %a, <256 x i32> addrspace(1)* %outptr
; mark 128-bit SGPR registers as used so they are unavailable for the
; scratch resource descriptor
call void asm sideeffect "", "~{SGPR4},~{SGPR8},~{SGPR12},~{SGPR16},~{SGPR20},~{SGPR24},~{SGPR28}" ()
call void asm sideeffect "", "~{SGPR32},~{SGPR36},~{SGPR40},~{SGPR44},~{SGPR48},~{SGPR52},~{SGPR56}" ()
call void asm sideeffect "", "~{SGPR60},~{SGPR64},~{SGPR68}" ()
ret void
}
declare i32 @llvm.SI.tid() nounwind readnone