[llvm] [AMDGPU,test] Add one more while-break case (PR #101300)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-backend-amdgpu

Author: Ruiling, Song (ruiling)

<details>
<summary>Changes</summary>

which suffers from v_mov issue.

---
Full diff: https://github.com/llvm/llvm-project/pull/101300.diff


1 Files Affected:

- (modified) llvm/test/CodeGen/AMDGPU/while-break.ll (+86) 


``````````diff
diff --git a/llvm/test/CodeGen/AMDGPU/while-break.ll b/llvm/test/CodeGen/AMDGPU/while-break.ll
index 13b37b40ee95c..46254994580d2 100644
--- a/llvm/test/CodeGen/AMDGPU/while-break.ll
+++ b/llvm/test/CodeGen/AMDGPU/while-break.ll
@@ -152,4 +152,90 @@ end:
   ret float %r
 }
 
+; Two chains of phi network that have the same value from %if block.
+define amdgpu_ps < 2 x float> @while_break_two_chains_of_phi(float %v, i32 %x, i32 %y, i32 %z, ptr addrspace(1) %p) #0 {
+; GCN-LABEL: while_break_two_chains_of_phi:
+; GCN:       ; %bb.0: ; %entry
+; GCN-NEXT:    v_mov_b32_e32 v6, 0
+; GCN-NEXT:    s_mov_b32 s2, 0
+; GCN-NEXT:    s_mov_b32 s0, 0
+; GCN-NEXT:    s_branch .LBB2_2
+; GCN-NEXT:  .LBB2_1: ; %Flow1
+; GCN-NEXT:    ; in Loop: Header=BB2_2 Depth=1
+; GCN-NEXT:    s_or_b32 exec_lo, exec_lo, s1
+; GCN-NEXT:    s_and_b32 s1, exec_lo, s4
+; GCN-NEXT:    s_or_b32 s2, s1, s2
+; GCN-NEXT:    s_andn2_b32 exec_lo, exec_lo, s2
+; GCN-NEXT:    s_cbranch_execz .LBB2_6
+; GCN-NEXT:  .LBB2_2: ; %header
+; GCN-NEXT:    ; =>This Inner Loop Header: Depth=1
+; GCN-NEXT:    v_cmp_ge_i32_e64 s3, s0, v1
+; GCN-NEXT:    v_cmp_lt_i32_e32 vcc_lo, s0, v1
+; GCN-NEXT:    s_and_saveexec_b32 s4, vcc_lo
+; GCN-NEXT:    s_cbranch_execz .LBB2_4
+; GCN-NEXT:  ; %bb.3: ; %if
+; GCN-NEXT:    ; in Loop: Header=BB2_2 Depth=1
+; GCN-NEXT:    s_ashr_i32 s1, s0, 31
+; GCN-NEXT:    s_lshl_b64 s[6:7], s[0:1], 2
+; GCN-NEXT:    s_andn2_b32 s1, s3, exec_lo
+; GCN-NEXT:    v_add_co_u32 v6, vcc_lo, v4, s6
+; GCN-NEXT:    v_add_co_ci_u32_e32 v7, vcc_lo, s7, v5, vcc_lo
+; GCN-NEXT:    v_cmp_lt_i32_e32 vcc_lo, s0, v2
+; GCN-NEXT:    global_load_dword v0, v[6:7], off
+; GCN-NEXT:    s_and_b32 s3, vcc_lo, exec_lo
+; GCN-NEXT:    s_or_b32 s3, s1, s3
+; GCN-NEXT:    s_waitcnt vmcnt(0)
+; GCN-NEXT:    v_add_f32_e32 v6, 1.0, v0
+; GCN-NEXT:    v_mov_b32_e32 v0, v6
+; GCN-NEXT:  .LBB2_4: ; %Flow
+; GCN-NEXT:    ; in Loop: Header=BB2_2 Depth=1
+; GCN-NEXT:    s_or_b32 exec_lo, exec_lo, s4
+; GCN-NEXT:    v_mov_b32_e32 v7, v6
+; GCN-NEXT:    s_mov_b32 s4, -1
+; GCN-NEXT:    s_and_saveexec_b32 s1, s3
+; GCN-NEXT:    s_cbranch_execz .LBB2_1
+; GCN-NEXT:  ; %bb.5: ; %latch
+; GCN-NEXT:    ; in Loop: Header=BB2_2 Depth=1
+; GCN-NEXT:    v_cmp_lt_i32_e32 vcc_lo, s0, v3
+; GCN-NEXT:    v_mov_b32_e32 v7, v0
+; GCN-NEXT:    s_add_i32 s0, s0, 1
+; GCN-NEXT:    s_orn2_b32 s4, vcc_lo, exec_lo
+; GCN-NEXT:    s_branch .LBB2_1
+; GCN-NEXT:  .LBB2_6: ; %end
+; GCN-NEXT:    s_or_b32 exec_lo, exec_lo, s2
+; GCN-NEXT:    v_mov_b32_e32 v0, v7
+; GCN-NEXT:    v_mov_b32_e32 v1, v6
+; GCN-NEXT:    ; return to shader part epilog
+entry:
+  br label %header
+
+header:
+  %v.1 = phi float [ %v, %entry ], [ %v.2, %latch ]
+  %v.copy = phi float [ 0.0, %entry ], [ %v.copy.2, %latch ]
+  %ind = phi i32 [ 0, %entry], [ %ind.inc, %latch ]
+  %cc = icmp slt i32 %ind, %x
+  br i1 %cc, label %if, label %latch
+
+if:
+  %v.ptr = getelementptr float, ptr addrspace(1) %p, i32 %ind
+  %v.load = load float, ptr addrspace(1) %v.ptr
+  %v.if = fadd float %v.load, 1.0
+  %cc2 = icmp slt i32 %ind, %y
+  br i1 %cc2, label %latch, label %end
+
+latch:
+  %v.2 = phi float [ %v.1, %header ], [ %v.if, %if ]
+  %v.copy.2 = phi float [ %v.copy, %header ], [ %v.if, %if ]
+  %ind.inc = add i32 %ind, 1
+  %cc3 = icmp slt i32 %ind, %z
+  br i1 %cc3, label %end, label %header
+
+end:
+  %r = phi float [ %v.2, %latch ], [ %v.if, %if ]
+  %r2 = phi float [ %v.copy.2, %latch ], [ %v.if, %if ]
+  %packed0 = insertelement < 2 x float > poison, float %r, i32 0
+  %packed1 = insertelement < 2 x float > %packed0, float %r2, i32 1
+  ret < 2 x float> %packed1
+}
+
 attributes #0 = { nounwind }

``````````

</details>


https://github.com/llvm/llvm-project/pull/101300