From 3c021b79b483af9fc8d5f8f9ef3befca851db699 Mon Sep 17 00:00:00 2001
From: Rhys Perry <pendingchaos02@gmail.com>
Date: Wed, 23 Apr 2025 15:38:32 +0100
Subject: [PATCH] aco/ra: use a correct stride for subdword get_reg_impl
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fossil-db (gfx1201):
Totals from 3 (0.00% of 79377) affected shaders:
Instrs: 1312 -> 1308 (-0.30%)
CodeSize: 7112 -> 7096 (-0.22%)
Latency: 5381 -> 5382 (+0.02%)
InvThroughput: 753 -> 752 (-0.13%)
Copies: 69 -> 68 (-1.45%)
VALU: 836 -> 835 (-0.12%)

Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/34679>
---
 src/amd/compiler/aco_register_allocation.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/amd/compiler/aco_register_allocation.cpp b/src/amd/compiler/aco_register_allocation.cpp
index b880ac60a52..bc9674a53f4 100644
--- a/src/amd/compiler/aco_register_allocation.cpp
+++ b/src/amd/compiler/aco_register_allocation.cpp
@@ -1271,7 +1271,7 @@ get_reg_impl(ra_ctx& ctx, const RegisterFile& reg_file, std::vector<parallelcopy
 {
    const PhysRegInterval& bounds = info.bounds;
    uint32_t size = info.size;
-   uint32_t stride = info.stride;
+   uint32_t stride = info.rc.is_subdword() ? DIV_ROUND_UP(info.stride, 4) : info.stride;
    RegClass rc = info.rc;
 
    /* check how many free regs we have */