caio/clang-p2996
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
Files
8cb2de7faecdd4e053dfc8468b2be84e2d8afb4e
clang-p2996/llvm/test/CodeGen/AMDGPU/GlobalISel/divergence-structurizer.ll
Petar Avramovic 06f711a906 AMDGPU/GlobalISelDivergenceLowering: select divergent i1 phis (#80003) 
Implement PhiLoweringHelper for GlobalISel in DivergenceLoweringHelper.
Use machine uniformity analysis to find divergent i1 phis and select
them as lane mask phis in same way SILowerI1Copies select VReg_1 phis.
Note that divergent i1 phis include phis created by LCSSA and all cases
of uses outside of cycle are actually covered by "lowering LCSSA phis".
GlobalISel lane masks are registers with sgpr register class and S1 LLT.

TODO: General goal is that instructions created in this pass are fully
instruction-selected so that selection of lane mask phis is not split
across multiple passes.

patch 3 from: https://github.com/llvm/llvm-project/pull/73337
2024-02-05 14:07:01 +01:00

465 lines
17 KiB
LLVM
Raw Blame History

; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 3
; RUN: llc -global-isel -mtriple=amdgcn-amd-amdpal -amdgpu-global-isel-risky-select -mcpu=gfx1010 -verify-machineinstrs < %s | FileCheck -check-prefix=GFX10 %s
; REQUIRES: do-not-run-me
; Simples case, if - then, that requires lane mask merging,
; %phi lane mask will hold %val_A at %A. Lanes that are active in %B
; will overwrite its own lane bit in lane mask with val_B
define amdgpu_ps void @divergent_i1_phi_if_then(ptr addrspace(1) %out, i32 %tid, i32 %cond) {
; GFX10-LABEL: divergent_i1_phi_if_then:
; GFX10: ; %bb.0: ; %A
; GFX10-NEXT: v_cmp_le_u32_e64 s0, 6, v2
; GFX10-NEXT: v_cmp_eq_u32_e32 vcc_lo, 0, v3
; GFX10-NEXT: s_and_saveexec_b32 s1, vcc_lo
; GFX10-NEXT: ; %bb.1: ; %B
; GFX10-NEXT: v_cmp_gt_u32_e64 s0, 1, v2
; GFX10-NEXT: ; %bb.2: ; %exit
; GFX10-NEXT: s_or_b32 exec_lo, exec_lo, s1
; GFX10-NEXT: v_cndmask_b32_e64 v2, 0, -1, s0
; GFX10-NEXT: v_add_nc_u32_e32 v2, 2, v2
; GFX10-NEXT: global_store_dword v[0:1], v2, off
; GFX10-NEXT: s_endpgm
A:
%val_A = icmp uge i32 %tid, 6
%cmp = icmp eq i32 %cond, 0
br i1 %cmp, label %B, label %exit
B:
%val_B = icmp ult i32 %tid, 1
br label %exit
exit:
%phi = phi i1 [ %val_A, %A ], [ %val_B, %B ]
%sel = select i1 %phi, i32 1, i32 2
store i32 %sel, ptr addrspace(1) %out
ret void
}
; if - else
define amdgpu_ps void @divergent_i1_phi_if_else(ptr addrspace(1) %out, i32 %tid, i32 %cond) {
; GFX10-LABEL: divergent_i1_phi_if_else:
; GFX10: ; %bb.0: ; %entry
; GFX10-NEXT: s_and_b32 s0, 1, s0
; GFX10-NEXT: v_cmp_ne_u32_e32 vcc_lo, 0, v3
; GFX10-NEXT: v_cmp_ne_u32_e64 s0, 0, s0
; GFX10-NEXT: s_and_saveexec_b32 s1, vcc_lo
; GFX10-NEXT: s_xor_b32 s1, exec_lo, s1
; GFX10-NEXT: ; %bb.1: ; %B
; GFX10-NEXT: v_cmp_gt_u32_e64 s0, 2, v2
; GFX10-NEXT: ; implicit-def: $vgpr2
; GFX10-NEXT: ; %bb.2: ; %Flow
; GFX10-NEXT: s_andn2_saveexec_b32 s1, s1
; GFX10-NEXT: ; %bb.3: ; %A
; GFX10-NEXT: v_cmp_le_u32_e64 s0, 1, v2
; GFX10-NEXT: ; %bb.4: ; %exit
; GFX10-NEXT: s_or_b32 exec_lo, exec_lo, s1
; GFX10-NEXT: v_cndmask_b32_e64 v2, 0, -1, s0
; GFX10-NEXT: v_add_nc_u32_e32 v2, 2, v2
; GFX10-NEXT: global_store_dword v[0:1], v2, off
; GFX10-NEXT: s_endpgm
entry:
%cmp = icmp eq i32 %cond, 0
br i1 %cmp, label %A, label %B
A:
%val_A = icmp uge i32 %tid, 1
br label %exit
B:
%val_B = icmp ult i32 %tid, 2
br label %exit
exit:
%phi = phi i1 [ %val_A, %A ], [ %val_B, %B ]
%sel = select i1 %phi, i32 1, i32 2
store i32 %sel, ptr addrspace(1) %out
ret void
}
; if - break;
; counter = 0;
; do {
; if (a[counter] == 0)
; break;
; if (b[counter] == 0)
; break;
; if (c[counter] == 0)
; break;
; x[counter++]+=1;
; } while (counter<100);
; Tests with multiple break conditions. Divergent phis will be used to track
; if any of the break conditions was reached. We only need to do simple lane
; mask merging (for current loop iteration only). There is an intrinsic,
; if_break, that will merge lane masks across all iterations of the loop.
define amdgpu_cs void @loop_with_1break(ptr addrspace(1) %x, ptr addrspace(1) %a) {
; GFX10-LABEL: loop_with_1break:
; GFX10: ; %bb.0: ; %entry
; GFX10-NEXT: s_mov_b32 s0, 0
; GFX10-NEXT: v_mov_b32_e32 v4, s0
; GFX10-NEXT: s_branch .LBB2_2
; GFX10-NEXT: .LBB2_1: ; %Flow
; GFX10-NEXT: ; in Loop: Header=BB2_2 Depth=1
; GFX10-NEXT: s_waitcnt_depctr 0xffe3
; GFX10-NEXT: s_or_b32 exec_lo, exec_lo, s1
; GFX10-NEXT: s_and_b32 s1, exec_lo, s2
; GFX10-NEXT: s_or_b32 s0, s1, s0
; GFX10-NEXT: s_andn2_b32 exec_lo, exec_lo, s0
; GFX10-NEXT: s_cbranch_execz .LBB2_4
; GFX10-NEXT: .LBB2_2: ; %A
; GFX10-NEXT: ; =>This Inner Loop Header: Depth=1
; GFX10-NEXT: v_ashrrev_i32_e32 v5, 31, v4
; GFX10-NEXT: s_mov_b32 s2, -1
; GFX10-NEXT: v_lshlrev_b64 v[5:6], 2, v[4:5]
; GFX10-NEXT: v_add_co_u32 v7, vcc_lo, v2, v5
; GFX10-NEXT: v_add_co_ci_u32_e32 v8, vcc_lo, v3, v6, vcc_lo
; GFX10-NEXT: global_load_dword v7, v[7:8], off
; GFX10-NEXT: s_waitcnt vmcnt(0)
; GFX10-NEXT: v_cmp_ne_u32_e32 vcc_lo, 0, v7
; GFX10-NEXT: s_and_saveexec_b32 s1, vcc_lo
; GFX10-NEXT: s_cbranch_execz .LBB2_1
; GFX10-NEXT: ; %bb.3: ; %loop.body
; GFX10-NEXT: ; in Loop: Header=BB2_2 Depth=1
; GFX10-NEXT: v_add_co_u32 v5, vcc_lo, v0, v5
; GFX10-NEXT: v_add_co_ci_u32_e32 v6, vcc_lo, v1, v6, vcc_lo
; GFX10-NEXT: v_add_nc_u32_e32 v8, 1, v4
; GFX10-NEXT: v_cmp_gt_u32_e64 s2, 0x64, v4
; GFX10-NEXT: global_load_dword v7, v[5:6], off
; GFX10-NEXT: v_mov_b32_e32 v4, v8
; GFX10-NEXT: s_waitcnt vmcnt(0)
; GFX10-NEXT: v_add_nc_u32_e32 v7, 1, v7
; GFX10-NEXT: global_store_dword v[5:6], v7, off
; GFX10-NEXT: s_branch .LBB2_1
; GFX10-NEXT: .LBB2_4: ; %exit
; GFX10-NEXT: s_endpgm
entry:
br label %A
A:
%counter = phi i32 [ %counter.plus.1, %loop.body ], [ 0, %entry ]
%a.plus.counter = getelementptr inbounds i32, ptr addrspace(1) %a, i32 %counter
%a.val = load i32, ptr addrspace(1) %a.plus.counter
%a.cond = icmp eq i32 %a.val, 0
br i1 %a.cond, label %exit, label %loop.body
loop.body:
%x.plus.counter = getelementptr inbounds i32, ptr addrspace(1) %x, i32 %counter
%x.val = load i32, ptr addrspace(1) %x.plus.counter
%x.val.plus.1 = add i32 %x.val, 1
store i32 %x.val.plus.1, ptr addrspace(1) %x.plus.counter
%counter.plus.1 = add i32 %counter, 1
%x.cond = icmp ult i32 %counter, 100
br i1 %x.cond, label %exit, label %A
exit:
ret void
}
define amdgpu_cs void @loop_with_2breaks(ptr addrspace(1) %x, ptr addrspace(1) %a, ptr addrspace(1) %b) {
; GFX10-LABEL: loop_with_2breaks:
; GFX10: ; %bb.0: ; %entry
; GFX10-NEXT: s_mov_b32 s0, 0
; GFX10-NEXT: v_mov_b32_e32 v6, s0
; GFX10-NEXT: s_branch .LBB3_3
; GFX10-NEXT: .LBB3_1: ; %Flow3
; GFX10-NEXT: ; in Loop: Header=BB3_3 Depth=1
; GFX10-NEXT: s_waitcnt_depctr 0xffe3
; GFX10-NEXT: s_or_b32 exec_lo, exec_lo, s3
; GFX10-NEXT: .LBB3_2: ; %Flow
; GFX10-NEXT: ; in Loop: Header=BB3_3 Depth=1
; GFX10-NEXT: s_or_b32 exec_lo, exec_lo, s1
; GFX10-NEXT: s_and_b32 s1, exec_lo, s2
; GFX10-NEXT: s_or_b32 s0, s1, s0
; GFX10-NEXT: s_andn2_b32 exec_lo, exec_lo, s0
; GFX10-NEXT: s_cbranch_execz .LBB3_6
; GFX10-NEXT: .LBB3_3: ; %A
; GFX10-NEXT: ; =>This Inner Loop Header: Depth=1
; GFX10-NEXT: v_ashrrev_i32_e32 v7, 31, v6
; GFX10-NEXT: s_mov_b32 s2, -1
; GFX10-NEXT: v_lshlrev_b64 v[7:8], 2, v[6:7]
; GFX10-NEXT: v_add_co_u32 v9, vcc_lo, v2, v7
; GFX10-NEXT: v_add_co_ci_u32_e32 v10, vcc_lo, v3, v8, vcc_lo
; GFX10-NEXT: global_load_dword v9, v[9:10], off
; GFX10-NEXT: s_waitcnt vmcnt(0)
; GFX10-NEXT: v_cmp_ne_u32_e32 vcc_lo, 0, v9
; GFX10-NEXT: s_and_saveexec_b32 s1, vcc_lo
; GFX10-NEXT: s_cbranch_execz .LBB3_2
; GFX10-NEXT: ; %bb.4: ; %B
; GFX10-NEXT: ; in Loop: Header=BB3_3 Depth=1
; GFX10-NEXT: v_add_co_u32 v9, vcc_lo, v4, v7
; GFX10-NEXT: v_add_co_ci_u32_e32 v10, vcc_lo, v5, v8, vcc_lo
; GFX10-NEXT: global_load_dword v9, v[9:10], off
; GFX10-NEXT: s_waitcnt vmcnt(0)
; GFX10-NEXT: v_cmp_ne_u32_e32 vcc_lo, 0, v9
; GFX10-NEXT: s_and_saveexec_b32 s3, vcc_lo
; GFX10-NEXT: s_cbranch_execz .LBB3_1
; GFX10-NEXT: ; %bb.5: ; %loop.body
; GFX10-NEXT: ; in Loop: Header=BB3_3 Depth=1
; GFX10-NEXT: v_add_co_u32 v7, vcc_lo, v0, v7
; GFX10-NEXT: v_add_co_ci_u32_e32 v8, vcc_lo, v1, v8, vcc_lo
; GFX10-NEXT: v_add_nc_u32_e32 v10, 1, v6
; GFX10-NEXT: v_cmp_gt_u32_e64 s2, 0x64, v6
; GFX10-NEXT: global_load_dword v9, v[7:8], off
; GFX10-NEXT: v_mov_b32_e32 v6, v10
; GFX10-NEXT: s_waitcnt vmcnt(0)
; GFX10-NEXT: v_add_nc_u32_e32 v9, 1, v9
; GFX10-NEXT: global_store_dword v[7:8], v9, off
; GFX10-NEXT: s_branch .LBB3_1
; GFX10-NEXT: .LBB3_6: ; %exit
; GFX10-NEXT: s_endpgm
entry:
br label %A
A:
%counter = phi i32 [ %counter.plus.1, %loop.body ], [ 0, %entry ]
%a.plus.counter = getelementptr inbounds i32, ptr addrspace(1) %a, i32 %counter
%a.val = load i32, ptr addrspace(1) %a.plus.counter
%a.cond = icmp eq i32 %a.val, 0
br i1 %a.cond, label %exit, label %B
B:
%b.plus.counter = getelementptr inbounds i32, ptr addrspace(1) %b, i32 %counter
%b.val = load i32, ptr addrspace(1) %b.plus.counter
%b.cond = icmp eq i32 %b.val, 0
br i1 %b.cond, label %exit, label %loop.body
loop.body:
%x.plus.counter = getelementptr inbounds i32, ptr addrspace(1) %x, i32 %counter
%x.val = load i32, ptr addrspace(1) %x.plus.counter
%x.val.plus.1 = add i32 %x.val, 1
store i32 %x.val.plus.1, ptr addrspace(1) %x.plus.counter
%counter.plus.1 = add i32 %counter, 1
%x.cond = icmp ult i32 %counter, 100
br i1 %x.cond, label %exit, label %A
exit:
ret void
}
define amdgpu_cs void @loop_with_3breaks(ptr addrspace(1) %x, ptr addrspace(1) %a, ptr addrspace(1) %b, ptr addrspace(1) %c) {
; GFX10-LABEL: loop_with_3breaks:
; GFX10: ; %bb.0: ; %entry
; GFX10-NEXT: s_mov_b32 s0, 0
; GFX10-NEXT: v_mov_b32_e32 v8, s0
; GFX10-NEXT: s_branch .LBB4_4
; GFX10-NEXT: .LBB4_1: ; %Flow5
; GFX10-NEXT: ; in Loop: Header=BB4_4 Depth=1
; GFX10-NEXT: s_waitcnt_depctr 0xffe3
; GFX10-NEXT: s_or_b32 exec_lo, exec_lo, s4
; GFX10-NEXT: .LBB4_2: ; %Flow4
; GFX10-NEXT: ; in Loop: Header=BB4_4 Depth=1
; GFX10-NEXT: s_or_b32 exec_lo, exec_lo, s3
; GFX10-NEXT: .LBB4_3: ; %Flow
; GFX10-NEXT: ; in Loop: Header=BB4_4 Depth=1
; GFX10-NEXT: s_or_b32 exec_lo, exec_lo, s1
; GFX10-NEXT: s_and_b32 s1, exec_lo, s2
; GFX10-NEXT: s_or_b32 s0, s1, s0
; GFX10-NEXT: s_andn2_b32 exec_lo, exec_lo, s0
; GFX10-NEXT: s_cbranch_execz .LBB4_8
; GFX10-NEXT: .LBB4_4: ; %A
; GFX10-NEXT: ; =>This Inner Loop Header: Depth=1
; GFX10-NEXT: v_ashrrev_i32_e32 v9, 31, v8
; GFX10-NEXT: s_mov_b32 s2, -1
; GFX10-NEXT: v_lshlrev_b64 v[9:10], 2, v[8:9]
; GFX10-NEXT: v_add_co_u32 v11, vcc_lo, v2, v9
; GFX10-NEXT: v_add_co_ci_u32_e32 v12, vcc_lo, v3, v10, vcc_lo
; GFX10-NEXT: global_load_dword v11, v[11:12], off
; GFX10-NEXT: s_waitcnt vmcnt(0)
; GFX10-NEXT: v_cmp_ne_u32_e32 vcc_lo, 0, v11
; GFX10-NEXT: s_and_saveexec_b32 s1, vcc_lo
; GFX10-NEXT: s_cbranch_execz .LBB4_3
; GFX10-NEXT: ; %bb.5: ; %B
; GFX10-NEXT: ; in Loop: Header=BB4_4 Depth=1
; GFX10-NEXT: v_add_co_u32 v11, vcc_lo, v4, v9
; GFX10-NEXT: v_add_co_ci_u32_e32 v12, vcc_lo, v5, v10, vcc_lo
; GFX10-NEXT: global_load_dword v11, v[11:12], off
; GFX10-NEXT: s_waitcnt vmcnt(0)
; GFX10-NEXT: v_cmp_ne_u32_e32 vcc_lo, 0, v11
; GFX10-NEXT: s_and_saveexec_b32 s3, vcc_lo
; GFX10-NEXT: s_cbranch_execz .LBB4_2
; GFX10-NEXT: ; %bb.6: ; %C
; GFX10-NEXT: ; in Loop: Header=BB4_4 Depth=1
; GFX10-NEXT: v_add_co_u32 v11, vcc_lo, v6, v9
; GFX10-NEXT: v_add_co_ci_u32_e32 v12, vcc_lo, v7, v10, vcc_lo
; GFX10-NEXT: global_load_dword v11, v[11:12], off
; GFX10-NEXT: s_waitcnt vmcnt(0)
; GFX10-NEXT: v_cmp_ne_u32_e32 vcc_lo, 0, v11
; GFX10-NEXT: s_and_saveexec_b32 s4, vcc_lo
; GFX10-NEXT: s_cbranch_execz .LBB4_1
; GFX10-NEXT: ; %bb.7: ; %loop.body
; GFX10-NEXT: ; in Loop: Header=BB4_4 Depth=1
; GFX10-NEXT: v_add_co_u32 v9, vcc_lo, v0, v9
; GFX10-NEXT: v_add_co_ci_u32_e32 v10, vcc_lo, v1, v10, vcc_lo
; GFX10-NEXT: v_add_nc_u32_e32 v12, 1, v8
; GFX10-NEXT: v_cmp_gt_u32_e64 s2, 0x64, v8
; GFX10-NEXT: global_load_dword v11, v[9:10], off
; GFX10-NEXT: v_mov_b32_e32 v8, v12
; GFX10-NEXT: s_waitcnt vmcnt(0)
; GFX10-NEXT: v_add_nc_u32_e32 v11, 1, v11
; GFX10-NEXT: global_store_dword v[9:10], v11, off
; GFX10-NEXT: s_branch .LBB4_1
; GFX10-NEXT: .LBB4_8: ; %exit
; GFX10-NEXT: s_endpgm
entry:
br label %A
A:
%counter = phi i32 [ %counter.plus.1, %loop.body ], [ 0, %entry ]
%a.plus.counter = getelementptr inbounds i32, ptr addrspace(1) %a, i32 %counter
%a.val = load i32, ptr addrspace(1) %a.plus.counter
%a.cond = icmp eq i32 %a.val, 0
br i1 %a.cond, label %exit, label %B
B:
%b.plus.counter = getelementptr inbounds i32, ptr addrspace(1) %b, i32 %counter
%b.val = load i32, ptr addrspace(1) %b.plus.counter
%b.cond = icmp eq i32 %b.val, 0
br i1 %b.cond, label %exit, label %C
C:
%c.plus.counter = getelementptr inbounds i32, ptr addrspace(1) %c, i32 %counter
%c.val = load i32, ptr addrspace(1) %c.plus.counter
%c.cond = icmp eq i32 %c.val, 0
br i1 %c.cond, label %exit, label %loop.body
loop.body:
%x.plus.counter = getelementptr inbounds i32, ptr addrspace(1) %x, i32 %counter
%x.val = load i32, ptr addrspace(1) %x.plus.counter
%x.val.plus.1 = add i32 %x.val, 1
store i32 %x.val.plus.1, ptr addrspace(1) %x.plus.counter
%counter.plus.1 = add i32 %counter, 1
%x.cond = icmp ult i32 %counter, 100
br i1 %x.cond, label %exit, label %A
exit:
ret void
}
; Divergent condition if with body, ending with break. This is loop with two
; exits but structurizer will create phi that will track exit from break
; and move break.body after the loop. Loop will then have one exit and phi
; used outside of the loop by condition used to enter the break.body.
define amdgpu_cs void @loop_with_div_break_with_body(ptr addrspace(1) %x, ptr addrspace(1) %a, ptr addrspace(1) %a.break) {
; GFX10-LABEL: loop_with_div_break_with_body:
; GFX10: ; %bb.0: ; %entry
; GFX10-NEXT: s_mov_b32 s0, 0
; GFX10-NEXT: v_mov_b32_e32 v6, s0
; GFX10-NEXT: s_branch .LBB5_2
; GFX10-NEXT: .LBB5_1: ; %Flow
; GFX10-NEXT: ; in Loop: Header=BB5_2 Depth=1
; GFX10-NEXT: s_waitcnt_depctr 0xffe3
; GFX10-NEXT: s_or_b32 exec_lo, exec_lo, s1
; GFX10-NEXT: s_and_b32 s1, exec_lo, s2
; GFX10-NEXT: s_or_b32 s0, s1, s0
; GFX10-NEXT: s_and_b32 s1, 1, s3
; GFX10-NEXT: v_cmp_ne_u32_e64 s1, 0, s1
; GFX10-NEXT: s_andn2_b32 exec_lo, exec_lo, s0
; GFX10-NEXT: s_cbranch_execz .LBB5_4
; GFX10-NEXT: .LBB5_2: ; %A
; GFX10-NEXT: ; =>This Inner Loop Header: Depth=1
; GFX10-NEXT: v_ashrrev_i32_e32 v7, 31, v6
; GFX10-NEXT: s_mov_b32 s2, -1
; GFX10-NEXT: s_mov_b32 s3, 1
; GFX10-NEXT: v_lshlrev_b64 v[7:8], 2, v[6:7]
; GFX10-NEXT: v_add_co_u32 v9, vcc_lo, v2, v7
; GFX10-NEXT: v_add_co_ci_u32_e32 v10, vcc_lo, v3, v8, vcc_lo
; GFX10-NEXT: global_load_dword v9, v[9:10], off
; GFX10-NEXT: s_waitcnt vmcnt(0)
; GFX10-NEXT: v_cmp_ne_u32_e32 vcc_lo, 0, v9
; GFX10-NEXT: s_and_saveexec_b32 s1, vcc_lo
; GFX10-NEXT: s_cbranch_execz .LBB5_1
; GFX10-NEXT: ; %bb.3: ; %loop.body
; GFX10-NEXT: ; in Loop: Header=BB5_2 Depth=1
; GFX10-NEXT: v_add_co_u32 v7, vcc_lo, v0, v7
; GFX10-NEXT: v_add_co_ci_u32_e32 v8, vcc_lo, v1, v8, vcc_lo
; GFX10-NEXT: v_add_nc_u32_e32 v10, 1, v6
; GFX10-NEXT: v_cmp_gt_u32_e64 s2, 0x64, v6
; GFX10-NEXT: s_mov_b32 s3, 0
; GFX10-NEXT: global_load_dword v9, v[7:8], off
; GFX10-NEXT: v_mov_b32_e32 v6, v10
; GFX10-NEXT: s_waitcnt vmcnt(0)
; GFX10-NEXT: v_add_nc_u32_e32 v9, 1, v9
; GFX10-NEXT: global_store_dword v[7:8], v9, off
; GFX10-NEXT: s_branch .LBB5_1
; GFX10-NEXT: .LBB5_4: ; %loop.exit.guard
; GFX10-NEXT: s_or_b32 exec_lo, exec_lo, s0
; GFX10-NEXT: s_and_saveexec_b32 s0, s1
; GFX10-NEXT: s_xor_b32 s0, exec_lo, s0
; GFX10-NEXT: s_cbranch_execz .LBB5_6
; GFX10-NEXT: ; %bb.5: ; %break.body
; GFX10-NEXT: v_mov_b32_e32 v0, 10
; GFX10-NEXT: global_store_dword v[4:5], v0, off
; GFX10-NEXT: .LBB5_6: ; %exit
; GFX10-NEXT: s_endpgm
entry:
br label %A
A:
%counter = phi i32 [ %counter.plus.1, %loop.body ], [ 0, %entry ]
%a.plus.counter = getelementptr inbounds i32, ptr addrspace(1) %a, i32 %counter
%a.val = load i32, ptr addrspace(1) %a.plus.counter
%a.cond = icmp eq i32 %a.val, 0
br i1 %a.cond, label %break.body, label %loop.body
break.body:
store i32 10, ptr addrspace(1) %a.break
br label %exit
loop.body:
%x.plus.counter = getelementptr inbounds i32, ptr addrspace(1) %x, i32 %counter
%x.val = load i32, ptr addrspace(1) %x.plus.counter
%x.val.plus.1 = add i32 %x.val, 1
store i32 %x.val.plus.1, ptr addrspace(1) %x.plus.counter
%counter.plus.1 = add i32 %counter, 1
%x.cond = icmp ult i32 %counter, 100
br i1 %x.cond, label %exit, label %A
exit:
ret void
}
; Snippet from test generated by the GraphicsFuzz tool, frontend generates ir
; with irreducible control flow graph. FixIrreducible converts it into natural
; loop and in the process creates i1 phi with three incoming values.
; int loop(int x, int y, int a0, int a1, int a2, int a3, int a4) {
; do {
; if (y < a2) {
; do {
; } while (x < a2);
; }
; if (x < a3) {
; return a1;
; }
; } while (y < a2);
; return a0;
; }
; This test is also interesting because it has phi with three incomings
;define amdgpu_ps i32 @irreducible_cfg(i32 %x, i32 %y, i32 %a0, i32 %a1, i32 %a2, i32 %a3) {
;.entry:
; %.y_lt_a2 = icmp sgt i32 %a2, %y
; %.x_lt_a2 = icmp sgt i32 %a2, %x
; %.x_lt_a3 = icmp sgt i32 %a3, %x
; br i1 %.y_lt_a2, label %.preheader, label %.loopexit ; first iteration, jump to inner loop if 'y < a2' or start with 'if (x < a3)'
;
;.preheader: ; if (y < a2),
; br label %.inner_loop
;
;.inner_loop: ; do while x < a2
; br i1 %.x_lt_a2, label %.inner_loop, label %.loopexit
;
;.loopexit: ; if x < a3
; %not.inner_loop = xor i1 %.y_lt_a2, true
; %brmerge = select i1 %.x_lt_a3, i1 true, i1 %not.inner_loop ; exit loop if 'x < a3' or 'loop ends since !(y < a2)'
; %.ret = select i1 %.x_lt_a3, i32 %a1, i32 %a0 ; select retrun value a1 'x < a3' or a0 'loop ends'
; br i1 %brmerge, label %.exit, label %.preheader
;
;.exit:
; ret i32 %.ret
;}
Reference in New Issue View Git Blame Copy Permalink