[llvm] [DirectX] Add support for vector type checking in DXIL Shader Flag Analysis (PR #150532)

[Deric C. via llvm-commits]

https://github.com/Icohedron created https://github.com/llvm/llvm-project/pull/150532

Fixes #150482 by replacing all `Instruction.getType()` in DXILShaderFlags.cpp with `Instruction.getType()->getScalarType()` to account for vectors types as suggested by @bogner 

>From b5263f733ccd4407e20124fd39b8da88c5685e73 Mon Sep 17 00:00:00 2001
From: Deric Cheung <dericcheung at microsoft.com>
Date: Thu, 24 Jul 2025 21:38:55 +0000
Subject: [PATCH] Account for vectors in shader flag analysis type checks

---
 llvm/lib/Target/DirectX/DXILShaderFlags.cpp   | 15 ++++---
 .../ShaderFlags/rawbuffer-low-precision.ll    | 44 +++++++++++++++++++
 2 files changed, 52 insertions(+), 7 deletions(-)
 create mode 100644 llvm/test/CodeGen/DirectX/ShaderFlags/rawbuffer-low-precision.ll

diff --git a/llvm/lib/Target/DirectX/DXILShaderFlags.cpp b/llvm/lib/Target/DirectX/DXILShaderFlags.cpp
index eb4adfea5aed6..e7e7f2ce66ae8 100644
--- a/llvm/lib/Target/DirectX/DXILShaderFlags.cpp
+++ b/llvm/lib/Target/DirectX/DXILShaderFlags.cpp
@@ -106,11 +106,11 @@ void ModuleShaderFlags::updateFunctionFlags(ComputedShaderFlags &CSF,
                                             DXILResourceTypeMap &DRTM,
                                             const ModuleMetadataInfo &MMDI) {
   if (!CSF.Doubles)
-    CSF.Doubles = I.getType()->isDoubleTy();
+    CSF.Doubles = I.getType()->getScalarType()->isDoubleTy();
 
   if (!CSF.Doubles) {
     for (const Value *Op : I.operands()) {
-      if (Op->getType()->isDoubleTy()) {
+      if (Op->getType()->getScalarType()->isDoubleTy()) {
         CSF.Doubles = true;
         break;
       }
@@ -130,12 +130,13 @@ void ModuleShaderFlags::updateFunctionFlags(ComputedShaderFlags &CSF,
   }
 
   if (!CSF.LowPrecisionPresent)
-    CSF.LowPrecisionPresent =
-        I.getType()->isIntegerTy(16) || I.getType()->isHalfTy();
+    CSF.LowPrecisionPresent = I.getType()->getScalarType()->isIntegerTy(16) ||
+                              I.getType()->getScalarType()->isHalfTy();
 
   if (!CSF.LowPrecisionPresent) {
     for (const Value *Op : I.operands()) {
-      if (Op->getType()->isIntegerTy(16) || Op->getType()->isHalfTy()) {
+      if (Op->getType()->getScalarType()->isIntegerTy(16) ||
+          Op->getType()->getScalarType()->isHalfTy()) {
         CSF.LowPrecisionPresent = true;
         break;
       }
@@ -150,11 +151,11 @@ void ModuleShaderFlags::updateFunctionFlags(ComputedShaderFlags &CSF,
   }
 
   if (!CSF.Int64Ops)
-    CSF.Int64Ops = I.getType()->isIntegerTy(64);
+    CSF.Int64Ops = I.getType()->getScalarType()->isIntegerTy(64);
 
   if (!CSF.Int64Ops && !isa<LifetimeIntrinsic>(&I)) {
     for (const Value *Op : I.operands()) {
-      if (Op->getType()->isIntegerTy(64)) {
+      if (Op->getType()->getScalarType()->isIntegerTy(64)) {
         CSF.Int64Ops = true;
         break;
       }
diff --git a/llvm/test/CodeGen/DirectX/ShaderFlags/rawbuffer-low-precision.ll b/llvm/test/CodeGen/DirectX/ShaderFlags/rawbuffer-low-precision.ll
new file mode 100644
index 0000000000000..ec4b87fd81799
--- /dev/null
+++ b/llvm/test/CodeGen/DirectX/ShaderFlags/rawbuffer-low-precision.ll
@@ -0,0 +1,44 @@
+; RUN: opt -S --passes="print-dx-shader-flags" 2>&1 %s | FileCheck %s
+; RUN: llc %s --filetype=obj -o - | obj2yaml | FileCheck %s --check-prefix=DXC
+
+target triple = "dxil-pc-shadermodel6.7-library"
+
+; CHECK: ; Combined Shader Flags for Module
+; CHECK-NEXT: ; Shader Flags Value: 0x00800030
+; CHECK-NEXT: ;
+; CHECK-NEXT: ; Note: shader requires additional functionality:
+; CHECK-NEXT: ;       Native low-precision data types
+; CHECK-NEXT: ; Note: extra DXIL module flags:
+; CHECK-NEXT: ;       Raw and structured buffers
+; CHECK-NEXT: ;       Low-precision data types present
+; CHECK-NEXT: ;       Enable native low-precision data types
+; CHECK-NEXT: ;
+; CHECK-NEXT: ; Shader Flags for Module Functions
+
+; CHECK: Function rawbuf : 0x00800030
+define void @rawbuf() "hlsl.export" {
+  %halfrb = tail call target("dx.RawBuffer", <4 x half>, 0, 0)
+    @llvm.dx.resource.handlefrombinding.tdx.RawBuffer_v4f16_0_0t(i32 0, i32 0, i32 1, i32 0, i1 false, ptr null)
+  %i16rb = tail call target("dx.RawBuffer", <4 x i16>, 1, 0)
+    @llvm.dx.resource.handlefrombinding.tdx.RawBuffer_v4i16_1_0t(i32 0, i32 1, i32 1, i32 0, i1 false, ptr null)
+  %loadhalfrb = call { <4 x i16>, i1 }
+    @llvm.dx.resource.load.rawbuffer.v4i16.tdx.RawBuffer_v4f16_0_0t(target("dx.RawBuffer", <4 x half>, 0, 0) %halfrb, i32 0, i32 0)
+  %storei16rb = extractvalue { <4 x i16>, i1 } %loadhalfrb, 0
+  call void @llvm.dx.resource.store.rawbuffer.tdx.RawBuffer_v4i16_1_0t.v4i16(target("dx.RawBuffer", <4 x i16>, 1, 0) %i16rb, i32 0, i32 0, <4 x i16> %storei16rb)
+  ret void
+}
+
+; Metadata to avoid adding flags not currently of interest to this test, and
+; enable native low precision data types
+!dx.valver = !{!0}
+!0 = !{i32 1, i32 8}
+!llvm.module.flags = !{!1, !2}
+!1 = !{i32 1, !"dx.nativelowprec", i32 1}
+!2 = !{i32 1, !"dx.resmayalias", i32 1}
+
+; DXC: - Name:            SFI0
+; DXC-NEXT:     Size:            8
+; DXC-NEXT:     Flags:
+; DXC:      MinimumPrecision: false
+; DXC:      NativeLowPrecision: true
+; DXC: ...