[llvm] [DirectX] Add static sampler support to root signature (PR #143422)

[via llvm-commits]

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@@ -261,6 +269,81 @@ static bool parseDescriptorTable(LLVMContext *Ctx,
   return false;
 }
 
+static bool parseStaticSampler(LLVMContext *Ctx, mcdxbc::RootSignatureDesc &RSD,
+                               MDNode *StaticSamplerNode) {
+  if (StaticSamplerNode->getNumOperands() != 14)
+    return reportError(Ctx, "Invalid format for Static Sampler");
+
+  dxbc::RTS0::v1::StaticSampler Sampler;
+  if (std::optional<uint32_t> Val = extractMdIntValue(StaticSamplerNode, 1))
+    Sampler.Filter = *Val;
+  else
+    return reportError(Ctx, "Invalid value for Filter");
+
+  if (std::optional<uint32_t> Val = extractMdIntValue(StaticSamplerNode, 2))
+    Sampler.AddressU = *Val;
+  else
+    return reportError(Ctx, "Invalid value for AddressU");
+
+  if (std::optional<uint32_t> Val = extractMdIntValue(StaticSamplerNode, 3))
+    Sampler.AddressV = *Val;
+  else
+    return reportError(Ctx, "Invalid value for AddressV");
+
+  if (std::optional<uint32_t> Val = extractMdIntValue(StaticSamplerNode, 4))
+    Sampler.AddressW = *Val;
+  else
+    return reportError(Ctx, "Invalid value for AddressW");
+
+  if (std::optional<APFloat> Val = extractMdFloatValue(StaticSamplerNode, 5))
+    Sampler.MipLODBias = Val->convertToFloat();
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joaosaffran wrote:

I did some research, I don't think `convertToFloat` to float, at least, I didn't see any error handling for it specifically. I moved to inside the extract function anyway.

https://github.com/llvm/llvm-project/pull/143422