-
Notifications
You must be signed in to change notification settings - Fork 10.8k
New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
AMDGPU: Document more backend recognized attributes #80239
Conversation
@llvm/pr-subscribers-backend-amdgpu Author: Matt Arsenault (arsenm) ChangesFull diff: https://github.com/llvm/llvm-project/pull/80239.diff 1 Files Affected:
diff --git a/llvm/docs/AMDGPUUsage.rst b/llvm/docs/AMDGPUUsage.rst
index 6b2417143ca06..ee4af9f51998e 100644
--- a/llvm/docs/AMDGPUUsage.rst
+++ b/llvm/docs/AMDGPUUsage.rst
@@ -1312,6 +1312,31 @@ The AMDGPU backend supports the following LLVM IR attributes.
the frame. This is an internal detail of how LDS variables are lowered,
language front ends should not set this attribute.
+ "amdgpu-gds-size" Bytes expected to be allocated at the start of GDS memory at entry.
+
+ "amdgpu-git-ptr-high" The hard-wired high half of the address of the global information table
+ for AMDPAL OS type. 0xffffffff represents no hard-wired high half, since
+ current hardware only allows a 16 bit value.
+
+ "amdgpu-32bit-address-high-bits" Assumed high 32-bits for
+ 32-bit address spaces which are really truncated
+ 64-bit addresses (i.e., addrspace(6))
+
+ "amdgpu-color-export" Assumed 1 for :ref:`amdgpu_ps <amdgpu_ps>`, and 0 for other calling conventions.
+
+ "amdgpu-depth-export" ..TODO:: Describe.
+
+ "InitialPSInputAddr" ..TODO:: Describe.
+
+
+ "amdgpu-wave-priority-threshold" ..TODO:: Describe.
+
+ "amdgpu-memory-bound". Set internally by backend
+
+ "amdgpu-wave-limiter" Set internally by backend
+
+ "amdgpu-unroll-threshold" ..TODO:: Describe.
+
======================================= ==========================================================
Calling Conventions
@@ -1397,7 +1422,7 @@ The AMDGPU backend supports the following calling conventions:
``amdgpu_ls`` Used for AMDPAL vertex shader if tessellation is in use.
..TODO::
Describe.
-
+.. _amdgpu_ps:
``amdgpu_ps`` Used for Mesa/AMDPAL pixel shaders.
..TODO::
Describe.
|
llvm/docs/AMDGPUUsage.rst
Outdated
@@ -1438,7 +1438,10 @@ The AMDGPU backend supports the following LLVM IR attributes. | |||
:ref:`amdgpu_ps <amdgpu_ps>` shaders. Any bits enabled by this value will | |||
be enabled in the final register value. | |||
|
|||
"amdgpu-wave-priority-threshold" ..TODO:: Describe. | |||
"amdgpu-wave-priority-threshold" VALU instruction count threshold for adjusting wave priority. If exceeded, |
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
ping @kosarev
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
The description looks correct to me. The pass was never proven useful though, if I recall correctly.
ping |
1 similar comment
ping |
"amdgpu-memory-bound" Set internally by backend | ||
|
||
"amdgpu-wave-limiter" Set internally by backend |
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
LLPC sets these in some cases. Any explicit setting takes precedence over the backend's internal heuristics. But I'm not sure if we want to document that.
No description provided.