[llvm] [SPIRV] Promote scalar arguments to vector for `OpExtInst` in `generateExtInst` instead of `SPIRVRegularizer` (PR #170155)

[Marcos Maronas via llvm-commits]

Juan Manuel Martinez =?utf-8?q?Caamaño?=,
Juan Manuel Martinez =?utf-8?q?Caamaño?=,
Juan Manuel Martinez =?utf-8?q?Caamaño?=,
Juan Manuel Martinez =?utf-8?q?Caamaño?=,
Juan Manuel Martinez =?utf-8?q?Caamaño?=,
Juan Manuel Martinez =?utf-8?q?Caamaño?Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/170155 at github.com>


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@@ -1157,10 +1157,63 @@ static unsigned getNumSizeComponents(SPIRVType *imgType) {
   return arrayed ? numComps + 1 : numComps;
 }
 
+static bool builtinMayNeedPromotionToVec(uint32_t BuiltinNumber) {
+  switch (BuiltinNumber) {
+  case SPIRV::OpenCLExtInst::s_min:
+  case SPIRV::OpenCLExtInst::u_min:
+  case SPIRV::OpenCLExtInst::s_max:
+  case SPIRV::OpenCLExtInst::u_max:
+  case SPIRV::OpenCLExtInst::fmax:
+  case SPIRV::OpenCLExtInst::fmin:
+  case SPIRV::OpenCLExtInst::fmax_common:
+  case SPIRV::OpenCLExtInst::fmin_common:
+  case SPIRV::OpenCLExtInst::s_clamp:
+  case SPIRV::OpenCLExtInst::fclamp:
+  case SPIRV::OpenCLExtInst::u_clamp:
+  case SPIRV::OpenCLExtInst::mix:
+  case SPIRV::OpenCLExtInst::step:
+  case SPIRV::OpenCLExtInst::smoothstep:
+    return true;
+  default:
+    break;
+  }
+  return false;
+}
+
 //===----------------------------------------------------------------------===//
 // Implementation functions for each builtin group
 //===----------------------------------------------------------------------===//
 
+static SmallVector<Register>
+getBuiltinCallArguments(const SPIRV::IncomingCall *Call, uint32_t BuiltinNumber,
+                        MachineIRBuilder &MIRBuilder, SPIRVGlobalRegistry *GR) {
+
+  Register ReturnTypeId = GR->getSPIRVTypeID(Call->ReturnType);
+  unsigned ResultElementCount =
+      GR->getScalarOrVectorComponentCount(ReturnTypeId);
+  bool MayNeedPromotionToVec =
+      builtinMayNeedPromotionToVec(BuiltinNumber) && ResultElementCount > 1;
+
+  if (!MayNeedPromotionToVec)
+    return {Call->Arguments.begin(), Call->Arguments.end()};
+
+  SmallVector<Register> Arguments;
+  for (Register Argument : Call->Arguments) {
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maarquitos14 wrote:

This is triggering copies for each `Argument`. Is this on purpose? Do we need copies?

https://github.com/llvm/llvm-project/pull/170155