From 4a39db797b99bd845dd0ff7d5875b5c6fa2e8794 Mon Sep 17 00:00:00 2001
From: Giovanni Mascellani <gmascellani@codeweavers.com>
Date: Tue, 10 Jun 2025 16:57:57 +0200
Subject: [PATCH] vkd3d-shader/ir: Introduce VKD3DSIH_IMUL_LOW.

It is meant to compute the lower word of an integer multiplication.
---
 libs/vkd3d-shader/dxil.c                 | 6 +++---
 libs/vkd3d-shader/glsl.c                 | 3 +++
 libs/vkd3d-shader/ir.c                   | 2 ++
 libs/vkd3d-shader/spirv.c                | 2 ++
 libs/vkd3d-shader/vkd3d_shader_private.h | 1 +
 5 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/libs/vkd3d-shader/dxil.c b/libs/vkd3d-shader/dxil.c
index 71fa81ec1..194c51a6f 100644
--- a/libs/vkd3d-shader/dxil.c
+++ b/libs/vkd3d-shader/dxil.c
@@ -4516,7 +4516,7 @@ static enum vkd3d_shader_opcode map_binary_op(uint64_t code, const struct sm6_ty
             is_valid = is_int && !is_bool;
             break;
         case BINOP_MUL:
-            op = is_int ? VKD3DSIH_UMUL : (is_double ? VKD3DSIH_DMUL : VKD3DSIH_MUL);
+            op = is_int ? VKD3DSIH_IMUL_LOW : (is_double ? VKD3DSIH_DMUL : VKD3DSIH_MUL);
             is_valid = !is_bool;
             break;
         case BINOP_OR:
@@ -4603,7 +4603,7 @@ static void sm6_parser_emit_binop(struct sm6_parser *sm6, const struct dxil_reco
             silence_warning = !(flags & ~(FP_NO_NAN | FP_NO_INF | FP_NO_SIGNED_ZEROS | FP_ALLOW_RECIPROCAL));
             break;
         case VKD3DSIH_IADD:
-        case VKD3DSIH_UMUL:
+        case VKD3DSIH_IMUL_LOW:
         case VKD3DSIH_ISHL:
             silence_warning = !(flags & ~(OB_NO_UNSIGNED_WRAP | OB_NO_SIGNED_WRAP));
             break;
@@ -4637,7 +4637,7 @@ static void sm6_parser_emit_binop(struct sm6_parser *sm6, const struct dxil_reco
 
     dst->type = a->type;
 
-    if (handler_idx == VKD3DSIH_UMUL || handler_idx == VKD3DSIH_UDIV || handler_idx == VKD3DSIH_IDIV)
+    if (handler_idx == VKD3DSIH_UDIV || handler_idx == VKD3DSIH_IDIV)
     {
         struct vkd3d_shader_dst_param *dst_params = instruction_dst_params_alloc(ins, 2, sm6);
         unsigned int index = code != BINOP_UDIV && code != BINOP_SDIV;
diff --git a/libs/vkd3d-shader/glsl.c b/libs/vkd3d-shader/glsl.c
index 214632c00..bf47474f3 100644
--- a/libs/vkd3d-shader/glsl.c
+++ b/libs/vkd3d-shader/glsl.c
@@ -1587,6 +1587,9 @@ static void vkd3d_glsl_handle_instruction(struct vkd3d_glsl_generator *gen,
         case VKD3DSIH_IMUL:
             shader_glsl_mul_extended(gen, ins);
             break;
+        case VKD3DSIH_IMUL_LOW:
+            shader_glsl_binop(gen, ins, "*");
+            break;
         case VKD3DSIH_INE:
         case VKD3DSIH_NEU:
             shader_glsl_relop(gen, ins, "!=", "notEqual");
diff --git a/libs/vkd3d-shader/ir.c b/libs/vkd3d-shader/ir.c
index 8489d0b5e..7d56c0c1e 100644
--- a/libs/vkd3d-shader/ir.c
+++ b/libs/vkd3d-shader/ir.c
@@ -208,6 +208,7 @@ const char *vsir_opcode_get_name(enum vkd3d_shader_opcode op, const char *error)
         [VKD3DSIH_IMM_ATOMIC_UMIN                 ] = "imm_atomic_umin",
         [VKD3DSIH_IMM_ATOMIC_XOR                  ] = "imm_atomic_xor",
         [VKD3DSIH_IMUL                            ] = "imul",
+        [VKD3DSIH_IMUL_LOW                        ] = "imul_low",
         [VKD3DSIH_INE                             ] = "ine",
         [VKD3DSIH_INEG                            ] = "ineg",
         [VKD3DSIH_ISFINITE                        ] = "isfinite",
@@ -7841,6 +7842,7 @@ static bool vsir_src_is_masked(enum vkd3d_shader_opcode opcode, unsigned int src
         case VKD3DSIH_IMAX:
         case VKD3DSIH_IMIN:
         case VKD3DSIH_IMUL:
+        case VKD3DSIH_IMUL_LOW:
         case VKD3DSIH_INE:
         case VKD3DSIH_INEG:
         case VKD3DSIH_ISFINITE:
diff --git a/libs/vkd3d-shader/spirv.c b/libs/vkd3d-shader/spirv.c
index dc8465432..dd4c9743d 100644
--- a/libs/vkd3d-shader/spirv.c
+++ b/libs/vkd3d-shader/spirv.c
@@ -7534,6 +7534,7 @@ static SpvOp spirv_compiler_map_alu_instruction(const struct vkd3d_shader_instru
         {VKD3DSIH_FREM,       SpvOpFRem},
         {VKD3DSIH_FTOD,       SpvOpFConvert},
         {VKD3DSIH_IADD,       SpvOpIAdd},
+        {VKD3DSIH_IMUL_LOW,   SpvOpIMul},
         {VKD3DSIH_INEG,       SpvOpSNegate},
         {VKD3DSIH_ISHL,       SpvOpShiftLeftLogical},
         {VKD3DSIH_ISHR,       SpvOpShiftRightArithmetic},
@@ -10671,6 +10672,7 @@ static int spirv_compiler_handle_instruction(struct spirv_compiler *compiler,
         case VKD3DSIH_FREM:
         case VKD3DSIH_FTOD:
         case VKD3DSIH_IADD:
+        case VKD3DSIH_IMUL_LOW:
         case VKD3DSIH_INEG:
         case VKD3DSIH_ISHL:
         case VKD3DSIH_ISHR:
diff --git a/libs/vkd3d-shader/vkd3d_shader_private.h b/libs/vkd3d-shader/vkd3d_shader_private.h
index 32cee4c78..6c940f1ed 100644
--- a/libs/vkd3d-shader/vkd3d_shader_private.h
+++ b/libs/vkd3d-shader/vkd3d_shader_private.h
@@ -456,6 +456,7 @@ enum vkd3d_shader_opcode
     VKD3DSIH_IMM_ATOMIC_UMIN,
     VKD3DSIH_IMM_ATOMIC_XOR,
     VKD3DSIH_IMUL,
+    VKD3DSIH_IMUL_LOW,
     VKD3DSIH_INE,
     VKD3DSIH_INEG,
     VKD3DSIH_ISFINITE,