[HLSL] Add the DXC matrix orientation flags

[farzonl]

fixes #58676

• Make /Zpr and /Zpc turn on the -fmatrix-memory-layout= row-major and column-major flags
• Add the new DXC driver flags to Options.td
• Error in the HLSL toolchain when both flags are specified
• Add the new error diagnostic to DiagnosticDriverKinds.td
• propogate the flag via the Clang toolchain

[llvmbot]

@llvm/pr-subscribers-hlsl
@llvm/pr-subscribers-clang

@llvm/pr-subscribers-clang-driver

Author: Farzon Lotfi (farzonl)

Changes

fixes #58676

• Make /Zpr and /Zpc turn on the -fmatrix-memory-layout= row-major and column-major flags
• Add the new DXC driver flags to Options.td
• Error in the HLSL toolchain when both flags are specified
• Add the new error diagnostic to DiagnosticDriverKinds.td
• propogate the flag via the Clang toolchain

---

Full diff: https://github.com/llvm/llvm-project/pull/171550.diff

5 Files Affected:

• (modified) clang/include/clang/Basic/DiagnosticDriverKinds.td (+2)
• (modified) clang/include/clang/Options/Options.td (+2)
• (modified) clang/lib/Driver/ToolChains/Clang.cpp (+4)
• (modified) clang/lib/Driver/ToolChains/HLSL.cpp (+4)
• (added) clang/test/Driver/hlsl_matrix_pack_order.hlsl (+8)

diff --git a/clang/include/clang/Basic/DiagnosticDriverKinds.td b/clang/include/clang/Basic/DiagnosticDriverKinds.td
index 3e6f7a2a430ff..fca84904326c9 100644
--- a/clang/include/clang/Basic/DiagnosticDriverKinds.td
+++ b/clang/include/clang/Basic/DiagnosticDriverKinds.td
@@ -826,6 +826,8 @@ def err_drv_target_variant_invalid : Error<
 
 def err_drv_invalid_directx_shader_module : Error<
   "invalid profile : %0">;
+def err_drv_dxc_invalid_matrix_layout : Error<
+  "cannot specify /Zpr and /Zpc together">;
 def err_drv_dxc_missing_target_profile : Error<
   "target profile option (-T) is missing">;
 def err_drv_hlsl_unsupported_target : Error<
diff --git a/clang/include/clang/Options/Options.td b/clang/include/clang/Options/Options.td
index e55146f0c7823..35fb9d5bd227a 100644
--- a/clang/include/clang/Options/Options.td
+++ b/clang/include/clang/Options/Options.td
@@ -9587,6 +9587,8 @@ class DXCJoinedOrSeparate<string name> : Option<["/", "-"], name,
   KIND_JOINED_OR_SEPARATE>, Group<dxc_Group>,
   Visibility<[DXCOption]>;
 
+def dxc_col_major : DXCFlag<"Zpc">, HelpText<"Pack matrices in column-major order">;
+def dxc_row_major : DXCFlag<"Zpr">, HelpText<"Pack matrices in row-major order">;
 def dxc_no_stdinc : DXCFlag<"hlsl-no-stdinc">,
   HelpText<"HLSL only. Disables all standard includes containing non-native compiler types and functions.">;
 def dxc_Fo : DXCJoinedOrSeparate<"Fo">,
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index 542b70b3e9d4c..b0d1c994de160 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -3723,6 +3723,10 @@ static void RenderHLSLOptions(const ArgList &Args, ArgStringList &CmdArgs,
   if (!Args.hasArg(options::OPT_dxc_no_stdinc) &&
       !Args.hasArg(options::OPT_nostdinc))
     CmdArgs.push_back("-finclude-default-header");
+  if (Args.hasArg(options::OPT_dxc_col_major))
+    CmdArgs.push_back("-fmatrix-memory-layout=column-major");
+  if (Args.hasArg(options::OPT_dxc_row_major))
+    CmdArgs.push_back("-fmatrix-memory-layout=row-major");
 }
 
 static void RenderOpenACCOptions(const Driver &D, const ArgList &Args,
diff --git a/clang/lib/Driver/ToolChains/HLSL.cpp b/clang/lib/Driver/ToolChains/HLSL.cpp
index 5d7221b8718a9..8f58b2f449a9a 100644
--- a/clang/lib/Driver/ToolChains/HLSL.cpp
+++ b/clang/lib/Driver/ToolChains/HLSL.cpp
@@ -412,6 +412,10 @@ HLSLToolChain::TranslateArgs(const DerivedArgList &Args, StringRef BoundArch,
 
   const OptTable &Opts = getDriver().getOpts();
 
+  if (Args.hasArg(options::OPT_dxc_col_major) &&
+      Args.hasArg(options::OPT_dxc_row_major))
+    getDriver().Diag(diag::err_drv_dxc_invalid_matrix_layout);
+
   for (Arg *A : Args) {
     if (A->getOption().getID() == options::OPT_dxil_validator_version) {
       StringRef ValVerStr = A->getValue();
diff --git a/clang/test/Driver/hlsl_matrix_pack_order.hlsl b/clang/test/Driver/hlsl_matrix_pack_order.hlsl
new file mode 100644
index 0000000000000..f7b6902fd02d8
--- /dev/null
+++ b/clang/test/Driver/hlsl_matrix_pack_order.hlsl
@@ -0,0 +1,8 @@
+// RUN: %clang_dxc -T lib_6_7  -Zpr -### %s 2>&1 | FileCheck %s  --check-prefix=CHECK-ROW-MAJOR
+// CHECK-ROW-MAJOR:  -fmatrix-memory-layout=row-major
+
+// RUN: %clang_dxc -T lib_6_7  -Zpc -### %s 2>&1 | FileCheck %s --check-prefix=CHECK-COL-MAJOR
+// CHECK-COL-MAJOR:  -fmatrix-memory-layout=column-major
+
+// RUN: not  %clang_dxc  -Tlib_6_7 -Zpr -Zpc -fcgl -Fo - %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-MISMATCH-MAJOR
+// CHECK-MISMATCH-MAJOR: cannot specify /Zpr and /Zpc together