promote-alloca-padding-size-estimate.ll
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; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=kaveri -mattr=-code-object-v3 -disable-promote-alloca-to-vector < %s | FileCheck -check-prefix=GCN %s
; This shows that the amount LDS size estimate should try to not be
; sensitive to the order of the LDS globals. This should try to
; estimate the worst case padding behavior to avoid overallocating
; LDS.
; These functions use the same amount of LDS, but the total, final
; size changes depending on the visit order of first use.
; The one with the suboptimal order resulting in extra padding exceeds
; the desired limit
; The padding estimate heuristic used by the promote alloca pass
; is mostly determined by the order of the globals,
; Raw usage = 1060 bytes
; Rounded usage:
; 292 + (4 pad) + 256 + (8 pad) + 512 = 1072
; 512 + (0 pad) + 256 + (0 pad) + 292 = 1060
; At default occupancy guess of 7, 2340 bytes available total.
; 1280 need to be left to promote alloca
; optimally packed, this requires
@lds0 = internal unnamed_addr addrspace(3) global [32 x <4 x i32>] undef, align 16
@lds2 = internal unnamed_addr addrspace(3) global [32 x i64] undef, align 8
@lds1 = internal unnamed_addr addrspace(3) global [73 x i32] undef, align 4
; GCN-LABEL: {{^}}promote_alloca_size_order_0:
; GCN: workgroup_group_segment_byte_size = 1060
define amdgpu_kernel void @promote_alloca_size_order_0(i32 addrspace(1)* nocapture %out, i32 addrspace(1)* nocapture %in, i32 %idx) #0 {
entry:
%stack = alloca [5 x i32], align 4, addrspace(5)
%tmp0 = load i32, i32 addrspace(1)* %in, align 4
%arrayidx1 = getelementptr inbounds [5 x i32], [5 x i32] addrspace(5)* %stack, i32 0, i32 %tmp0
store i32 4, i32 addrspace(5)* %arrayidx1, align 4
%arrayidx2 = getelementptr inbounds i32, i32 addrspace(1)* %in, i32 1
%tmp1 = load i32, i32 addrspace(1)* %arrayidx2, align 4
%arrayidx3 = getelementptr inbounds [5 x i32], [5 x i32] addrspace(5)* %stack, i32 0, i32 %tmp1
store i32 5, i32 addrspace(5)* %arrayidx3, align 4
%arrayidx10 = getelementptr inbounds [5 x i32], [5 x i32] addrspace(5)* %stack, i32 0, i32 0
%tmp2 = load i32, i32 addrspace(5)* %arrayidx10, align 4
store i32 %tmp2, i32 addrspace(1)* %out, align 4
%arrayidx12 = getelementptr inbounds [5 x i32], [5 x i32] addrspace(5)* %stack, i32 0, i32 1
%tmp3 = load i32, i32 addrspace(5)* %arrayidx12
%arrayidx13 = getelementptr inbounds i32, i32 addrspace(1)* %out, i32 1
store i32 %tmp3, i32 addrspace(1)* %arrayidx13
%gep.lds1 = getelementptr inbounds [73 x i32], [73 x i32] addrspace(3)* @lds1, i32 0, i32 %idx
store volatile i32 0, i32 addrspace(3)* %gep.lds1, align 4
%gep.lds2 = getelementptr inbounds [32 x i64], [32 x i64] addrspace(3)* @lds2, i32 0, i32 %idx
store volatile i64 0, i64 addrspace(3)* %gep.lds2, align 8
%gep.lds0 = getelementptr inbounds [32 x <4 x i32>], [32 x <4 x i32>] addrspace(3)* @lds0, i32 0, i32 %idx
store volatile <4 x i32> zeroinitializer, <4 x i32> addrspace(3)* %gep.lds0, align 16
ret void
}
; GCN-LABEL: {{^}}promote_alloca_size_order_1:
; GCN: workgroup_group_segment_byte_size = 1072
define amdgpu_kernel void @promote_alloca_size_order_1(i32 addrspace(1)* nocapture %out, i32 addrspace(1)* nocapture %in, i32 %idx) #0 {
entry:
%stack = alloca [5 x i32], align 4, addrspace(5)
%tmp0 = load i32, i32 addrspace(1)* %in, align 4
%arrayidx1 = getelementptr inbounds [5 x i32], [5 x i32] addrspace(5)* %stack, i32 0, i32 %tmp0
store i32 4, i32 addrspace(5)* %arrayidx1, align 4
%arrayidx2 = getelementptr inbounds i32, i32 addrspace(1)* %in, i32 1
%tmp1 = load i32, i32 addrspace(1)* %arrayidx2, align 4
%arrayidx3 = getelementptr inbounds [5 x i32], [5 x i32] addrspace(5)* %stack, i32 0, i32 %tmp1
store i32 5, i32 addrspace(5)* %arrayidx3, align 4
%arrayidx10 = getelementptr inbounds [5 x i32], [5 x i32] addrspace(5)* %stack, i32 0, i32 0
%tmp2 = load i32, i32 addrspace(5)* %arrayidx10, align 4
store i32 %tmp2, i32 addrspace(1)* %out, align 4
%arrayidx12 = getelementptr inbounds [5 x i32], [5 x i32] addrspace(5)* %stack, i32 0, i32 1
%tmp3 = load i32, i32 addrspace(5)* %arrayidx12
%arrayidx13 = getelementptr inbounds i32, i32 addrspace(1)* %out, i32 1
store i32 %tmp3, i32 addrspace(1)* %arrayidx13
%gep.lds0 = getelementptr inbounds [32 x <4 x i32>], [32 x <4 x i32>] addrspace(3)* @lds0, i32 0, i32 %idx
store volatile <4 x i32> zeroinitializer, <4 x i32> addrspace(3)* %gep.lds0, align 16
%gep.lds2 = getelementptr inbounds [32 x i64], [32 x i64] addrspace(3)* @lds2, i32 0, i32 %idx
store volatile i64 0, i64 addrspace(3)* %gep.lds2, align 8
%gep.lds1 = getelementptr inbounds [73 x i32], [73 x i32] addrspace(3)* @lds1, i32 0, i32 %idx
store volatile i32 0, i32 addrspace(3)* %gep.lds1, align 4
ret void
}
@lds3 = internal unnamed_addr addrspace(3) global [13 x i32] undef, align 4
@lds4 = internal unnamed_addr addrspace(3) global [63 x <4 x i32>] undef, align 16
; The guess from the alignment padding pushes this over the determined
; size limit, so it isn't promoted
; GCN-LABEL: {{^}}promote_alloca_align_pad_guess_over_limit:
; GCN: workgroup_group_segment_byte_size = 1060
define amdgpu_kernel void @promote_alloca_align_pad_guess_over_limit(i32 addrspace(1)* nocapture %out, i32 addrspace(1)* nocapture %in, i32 %idx) #0 {
entry:
%stack = alloca [5 x i32], align 4, addrspace(5)
%tmp0 = load i32, i32 addrspace(1)* %in, align 4
%arrayidx1 = getelementptr inbounds [5 x i32], [5 x i32] addrspace(5)* %stack, i32 0, i32 %tmp0
store i32 4, i32 addrspace(5)* %arrayidx1, align 4
%arrayidx2 = getelementptr inbounds i32, i32 addrspace(1)* %in, i32 1
%tmp1 = load i32, i32 addrspace(1)* %arrayidx2, align 4
%arrayidx3 = getelementptr inbounds [5 x i32], [5 x i32] addrspace(5)* %stack, i32 0, i32 %tmp1
store i32 5, i32 addrspace(5)* %arrayidx3, align 4
%arrayidx10 = getelementptr inbounds [5 x i32], [5 x i32] addrspace(5)* %stack, i32 0, i32 0
%tmp2 = load i32, i32 addrspace(5)* %arrayidx10, align 4
store i32 %tmp2, i32 addrspace(1)* %out, align 4
%arrayidx12 = getelementptr inbounds [5 x i32], [5 x i32] addrspace(5)* %stack, i32 0, i32 1
%tmp3 = load i32, i32 addrspace(5)* %arrayidx12
%arrayidx13 = getelementptr inbounds i32, i32 addrspace(1)* %out, i32 1
store i32 %tmp3, i32 addrspace(1)* %arrayidx13
%gep.lds3 = getelementptr inbounds [13 x i32], [13 x i32] addrspace(3)* @lds3, i32 0, i32 %idx
store volatile i32 0, i32 addrspace(3)* %gep.lds3, align 4
%gep.lds4 = getelementptr inbounds [63 x <4 x i32>], [63 x <4 x i32>] addrspace(3)* @lds4, i32 0, i32 %idx
store volatile <4 x i32> zeroinitializer, <4 x i32> addrspace(3)* %gep.lds4, align 16
ret void
}
attributes #0 = { nounwind "amdgpu-flat-work-group-size"="64,64" "amdgpu-waves-per-eu"="1,7" }