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clang-p2996/llvm/test/CodeGen/AMDGPU/illegal-eviction-assert.mir
Christudasan Devadasan ac0f64f06d [AMDGPU] Split vgpr regalloc pipeline (#93526)
Allocating wwm-registers and per-thread VGPR operands
together imposes many challenges in the way the
registers are reused during allocation. There are
times when regalloc reuses the registers of regular
VGPRs operations for wwm-operations in a small range
leading to unwantedly clobbering their inactive lanes
causing correctness issues that are hard to trace.

This patch splits the VGPR allocation pipeline further
to allocate wwm-registers first and the regular VGPR
operands in a separate pipeline. The splitting would
ensure that the physical registers used for wwm
allocations won't take part in the next allocation
pipeline to avoid any such clobbering.
2024-09-30 19:55:42 +05:30

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# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
# RUN: not llc -mtriple=amdgcn -mcpu=gfx900 -start-before=greedy,0 -stop-after=virtregrewriter,2 -o - 2>%t.err %s | FileCheck %s
# RUN: FileCheck -check-prefix=ERR %s < %t.err
# This testcase cannot be compiled. An attempted eviction legality
# check was inconsistent with a later assertion when the eviction was
# performed.
# ERR: error: ran out of registers during register allocation
--- |
define void @foo() #0 {
ret void
}
attributes #0 = { "amdgpu-waves-per-eu"="8,8" }
...
# CHECK: S_NOP 0, implicit-def renamable $vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17_vgpr18_vgpr19, implicit-def renamable $vgpr20_vgpr21_vgpr22_vgpr23_vgpr24_vgpr25_vgpr26_vgpr27, implicit-def renamable $vgpr0_vgpr1_vgpr2_vgpr3, implicit-def renamable $vgpr28_vgpr29_vgpr30_vgpr31, implicit-def renamable $vgpr0_vgpr1_vgpr2_vgpr3
# CHECK: S_NOP 0, implicit killed renamable $vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17_vgpr18_vgpr19, implicit killed renamable $vgpr20_vgpr21_vgpr22_vgpr23_vgpr24_vgpr25_vgpr26_vgpr27, implicit killed renamable $vgpr0_vgpr1_vgpr2_vgpr3, implicit killed renamable $vgpr28_vgpr29_vgpr30_vgpr31, implicit killed renamable $vgpr0_vgpr1_vgpr2_vgpr3
---
name: foo
tracksRegLiveness: true
machineFunctionInfo:
scratchRSrcReg: '$sgpr0_sgpr1_sgpr2_sgpr3'
frameOffsetReg: '$sgpr33'
stackPtrOffsetReg: '$sgpr32'
body: |
bb.0:
S_NOP 0, implicit-def %0:vreg_512, implicit-def %1:vreg_256, implicit-def %2:vreg_128, implicit-def %3:vreg_128, implicit-def %4:vreg_128
S_NOP 0, implicit %0, implicit %1, implicit %2, implicit %3, implicit %4
S_ENDPGM 0
...