[llvm] [AArch64][GlobalISel] Promote BF16 G_FCMP (PR #196093)

[Cullen Rhodes via llvm-commits]

================
@@ -450,33 +414,108 @@ define bfloat @test_select(bfloat %a, bfloat %b, i1 zeroext %c) #0 {
 }
 
 define bfloat @test_select_cc(bfloat %a, bfloat %b, bfloat %c, bfloat %d) #0 {
-; CHECK-LABEL: test_select_cc:
-; CHECK:       // %bb.0:
-; CHECK-NEXT:    // kill: def $h3 killed $h3 def $d3
-; CHECK-NEXT:    // kill: def $h2 killed $h2 def $d2
-; CHECK-NEXT:    // kill: def $h0 killed $h0 def $s0
-; CHECK-NEXT:    // kill: def $h1 killed $h1 def $s1
-; CHECK-NEXT:    shll v3.4s, v3.4h, #16
-; CHECK-NEXT:    shll v2.4s, v2.4h, #16
-; CHECK-NEXT:    fcmp s2, s3
-; CHECK-NEXT:    fcsel s0, s0, s1, ne
-; CHECK-NEXT:    // kill: def $h0 killed $h0 killed $s0
-; CHECK-NEXT:    ret
+; CHECK-CVT-SD-LABEL: test_select_cc:
+; CHECK-CVT-SD:       // %bb.0:
+; CHECK-CVT-SD-NEXT:    // kill: def $h3 killed $h3 def $d3
+; CHECK-CVT-SD-NEXT:    // kill: def $h2 killed $h2 def $d2
+; CHECK-CVT-SD-NEXT:    // kill: def $h0 killed $h0 def $s0
+; CHECK-CVT-SD-NEXT:    // kill: def $h1 killed $h1 def $s1
+; CHECK-CVT-SD-NEXT:    shll v3.4s, v3.4h, #16
+; CHECK-CVT-SD-NEXT:    shll v2.4s, v2.4h, #16
+; CHECK-CVT-SD-NEXT:    fcmp s2, s3
+; CHECK-CVT-SD-NEXT:    fcsel s0, s0, s1, ne
+; CHECK-CVT-SD-NEXT:    // kill: def $h0 killed $h0 killed $s0
+; CHECK-CVT-SD-NEXT:    ret
+;
+; CHECK-BF16-SD-LABEL: test_select_cc:
+; CHECK-BF16-SD:       // %bb.0:
+; CHECK-BF16-SD-NEXT:    // kill: def $h3 killed $h3 def $d3
+; CHECK-BF16-SD-NEXT:    // kill: def $h2 killed $h2 def $d2
+; CHECK-BF16-SD-NEXT:    // kill: def $h0 killed $h0 def $s0
+; CHECK-BF16-SD-NEXT:    // kill: def $h1 killed $h1 def $s1
+; CHECK-BF16-SD-NEXT:    shll v3.4s, v3.4h, #16
+; CHECK-BF16-SD-NEXT:    shll v2.4s, v2.4h, #16
+; CHECK-BF16-SD-NEXT:    fcmp s2, s3
+; CHECK-BF16-SD-NEXT:    fcsel s0, s0, s1, ne
+; CHECK-BF16-SD-NEXT:    // kill: def $h0 killed $h0 killed $s0
+; CHECK-BF16-SD-NEXT:    ret
+;
+; CHECK-CVT-GI-LABEL: test_select_cc:
+; CHECK-CVT-GI:       // %bb.0:
+; CHECK-CVT-GI-NEXT:    // kill: def $h2 killed $h2 def $d2
+; CHECK-CVT-GI-NEXT:    // kill: def $h3 killed $h3 def $d3
+; CHECK-CVT-GI-NEXT:    // kill: def $h0 killed $h0 def $s0
+; CHECK-CVT-GI-NEXT:    // kill: def $h1 killed $h1 def $s1
+; CHECK-CVT-GI-NEXT:    fmov w8, s0
+; CHECK-CVT-GI-NEXT:    fmov w9, s1
+; CHECK-CVT-GI-NEXT:    shll v2.4s, v2.4h, #16
+; CHECK-CVT-GI-NEXT:    shll v3.4s, v3.4h, #16
+; CHECK-CVT-GI-NEXT:    fcmp s2, s3
+; CHECK-CVT-GI-NEXT:    csel w8, w8, w9, ne
+; CHECK-CVT-GI-NEXT:    fmov s0, w8
+; CHECK-CVT-GI-NEXT:    // kill: def $h0 killed $h0 killed $s0
+; CHECK-CVT-GI-NEXT:    ret
+;
+; CHECK-BF16-GI-LABEL: test_select_cc:
+; CHECK-BF16-GI:       // %bb.0:
+; CHECK-BF16-GI-NEXT:    // kill: def $h2 killed $h2 def $d2
+; CHECK-BF16-GI-NEXT:    // kill: def $h3 killed $h3 def $d3
+; CHECK-BF16-GI-NEXT:    // kill: def $h0 killed $h0 def $s0
+; CHECK-BF16-GI-NEXT:    // kill: def $h1 killed $h1 def $s1
+; CHECK-BF16-GI-NEXT:    fmov w8, s0
+; CHECK-BF16-GI-NEXT:    fmov w9, s1
+; CHECK-BF16-GI-NEXT:    shll v2.4s, v2.4h, #16
+; CHECK-BF16-GI-NEXT:    shll v3.4s, v3.4h, #16
+; CHECK-BF16-GI-NEXT:    fcmp s2, s3
+; CHECK-BF16-GI-NEXT:    csel w8, w8, w9, ne
+; CHECK-BF16-GI-NEXT:    fmov s0, w8
+; CHECK-BF16-GI-NEXT:    // kill: def $h0 killed $h0 killed $s0
+; CHECK-BF16-GI-NEXT:    ret
----------------
c-rhodes wrote:

would it make sense to add common CHECK-SD / CHECK-GI prefixes to the RUN lines? Seems there's a few cases like this where CVT/BF16 check lines are common for a given instruction selector

https://github.com/llvm/llvm-project/pull/196093