[llvm] [SPIR-V] Handle bfloat in getZeroFP/getOneFP (PR #202859)

[Juan Manuel Martinez Caamaño via llvm-commits]

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@@ -25,3 +31,50 @@ entry:
   store <2 x bfloat> %data2, ptr @G2
   ret void
 }
+
+; CHECK-DAG: %[[#]] = OpConstantNull %[[#BFLOAT]]
+; CHECK-DAG: %[[#one:]] = OpConstant %[[#BFLOAT]] 16256
+; CHECK-DAG: %[[#]] = OpConstantNull %[[#VEC]]
+; CHECK-DAG: %[[#]] = OpConstantComposite %[[#VEC]] %[[#one]] %[[#one]]
+
+define spir_func bfloat @one_bfloat() {
+entry:
+  ret bfloat 1.0
+}
+
+define spir_func <2 x bfloat> @one_bfloat2() {
+entry:
+  ret <2 x bfloat> <bfloat 1.0, bfloat 1.0>
+}
+
+;--- saturate.ll
+; GLSL.std.450 defines its floating-point operands as IEEE 754 encoded
+; OpTypeFloat, so FClamp on bfloat is not currently representable in a
+; spirv-val-valid module. Check the lowering with FileCheck only.
+target datalayout = "e-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128-v192:256-v256:256-v512:512-v1024:1024-n8:16:32:64"
+target triple = "spir64-unknown-unknown"
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jmmartinez wrote:

```suggestion
```

https://github.com/llvm/llvm-project/pull/202859