From 23ee29a953c23bc4e6a19555f0376bf526968ab8 Mon Sep 17 00:00:00 2001
From: Henri Verbeet <hverbeet@locutus.nl>
Date: Wed, 3 Sep 2025 16:25:47 +0200
Subject: [PATCH] vkd3d-shader/hlsl: Implement constant folding of
 'reinterpret' expressions.

As encountered in tests/hlsl/frexp.shader_test.
---
 libs/vkd3d-shader/hlsl_constant_ops.c | 17 +++++++++++++++++
 tests/hlsl/frexp.shader_test          | 14 +++++++-------
 2 files changed, 24 insertions(+), 7 deletions(-)

diff --git a/libs/vkd3d-shader/hlsl_constant_ops.c b/libs/vkd3d-shader/hlsl_constant_ops.c
index 1262cfe89..492969ec6 100644
--- a/libs/vkd3d-shader/hlsl_constant_ops.c
+++ b/libs/vkd3d-shader/hlsl_constant_ops.c
@@ -508,6 +508,19 @@ static bool fold_rcp(struct hlsl_ctx *ctx, struct hlsl_constant_value *dst, cons
     return true;
 }
 
+static bool fold_reinterpret(struct hlsl_ctx *ctx, struct hlsl_constant_value *dst,
+        const struct hlsl_type *dst_type, const struct hlsl_ir_constant *src)
+{
+    unsigned int k;
+
+    for (k = 0; k < dst_type->e.numeric.dimx; ++k)
+    {
+        dst->u[k] = src->value.u[k];
+    }
+
+    return true;
+}
+
 static bool fold_rsq(struct hlsl_ctx *ctx, struct hlsl_constant_value *dst, const struct hlsl_type *dst_type,
         const struct hlsl_ir_constant *src, const struct vkd3d_shader_location *loc)
 {
@@ -1393,6 +1406,10 @@ bool hlsl_fold_constant_exprs(struct hlsl_ctx *ctx, struct hlsl_ir_node *instr,
             success = fold_rcp(ctx, &res, instr->data_type, arg1, &instr->loc);
             break;
 
+        case HLSL_OP1_REINTERPRET:
+            success = fold_reinterpret(ctx, &res, instr->data_type, arg1);
+            break;
+
         case HLSL_OP1_RSQ:
             success = fold_rsq(ctx, &res, instr->data_type, arg1, &instr->loc);
             break;
diff --git a/tests/hlsl/frexp.shader_test b/tests/hlsl/frexp.shader_test
index f0fd773a4..bbea71825 100644
--- a/tests/hlsl/frexp.shader_test
+++ b/tests/hlsl/frexp.shader_test
@@ -55,7 +55,7 @@ uniform 0 uint4 0x0007ffff 0 0 0
 todo(sm<4 | msl & sm>=6) draw quad
 probe (0, 0) f32(0, 0, 0, 0)
 
-[pixel shader todo(sm<4)]
+[pixel shader]
 float4 main() : sv_target
 {
     int arg = 7604;
@@ -66,10 +66,10 @@ float4 main() : sv_target
 }
 
 [test]
-todo(sm<4) draw quad
+draw quad
 probe (0, 0) f32(13.0, 0.0, 0.0, 0.0)
 
-[pixel shader todo(sm<4)]
+[pixel shader]
 float4 main() : sv_target
 {
     bool arg = true;
@@ -80,11 +80,11 @@ float4 main() : sv_target
 }
 
 [test]
-todo(sm<4) draw quad
-if(sm<4)  probe (0, 0) f32(0.0, 1.0, 0.0, 0.0)
+draw quad
+if(sm<4)  todo probe (0, 0) f32(0.0, 1.0, 0.0, 0.0)
 if(sm>=4) probe (0, 0) f32(1.0, 1.0, 0.0, 0.0)
 
-[pixel shader todo(sm<4)]
+[pixel shader]
 float4 main() : sv_target
 {
     half arg = 3.141;
@@ -95,7 +95,7 @@ float4 main() : sv_target
 }
 
 [test]
-todo(sm<4) draw quad
+draw quad
 probe (0, 0) f32(2.0, 0.785250008, 0.0, 0.0)
 
 [require]