Aaditya 0bd1c87996 [AMDGPU] Support divergent sized dynamic alloca (#121148) ...

Currently, AMDGPU backend can handle uniform-sized dynamic allocas. 
This patch extends support for divergent-sized dynamic allocas.
When the size argument of a dynamic alloca is divergent, 
a wave-wide reduction is performed to get the required stack space. 
`@llvm.amdgcn.wave.reduce.umax` is used to perform the 
wave reduction.

Dynamic allocas are not completely supported yet, 
as the stack is not properly restored on function exit.
This patch doesn't attempt to address the aforementioned issue.

Note: Compiler already Zero-Extends or Truncates all other 
types(of alloca size arg) to i32.

2025-01-06 12:28:24 +07:00

121 KiB

Raw Blame History

View Raw