fallback: legalize: G_SHUFFLE_VECTOR <4 x s8>
| Run: | main-04ca53e65f-20261014-113325 |
| Kind: | fallback |
| Category: | legalize: G_SHUFFLE_VECTOR <4 x s8> |
| Occurrences: | 3 in 1 configs, 2 test files |
| Snippet from: | rvp-reverse.ll @test_prev_v4i8 via llvm-extract |
| Config: | -mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs |
| Local check: | reproduces at 04ca53e65f |
| Compiler Explorer: | not uploaded (over --godbolt-limit or disabled) |
Snippet:
define <4 x i8> @test_prev_v4i8(<4 x i8> %a) {
%r = shufflevector <4 x i8> %a, <4 x i8> poison, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
ret <4 x i8> %r
}
Reproduce:
llc -mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs -global-isel -global-isel-abort=2 -pass-remarks-missed=gisel.* snippet.ll -o -
llc -mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs -global-isel=0 snippet.ll -o -
Local llc output:
remark: <unknown>:0:0: unable to legalize instruction: %3:_(<4 x s8>) = G_SHUFFLE_VECTOR %0:_(<4 x s8>), %4:_, shufflemask(3, 2, 1, 0) (in function: test_prev_v4i8)
warning: Instruction selection used fallback path for test_prev_v4i8
Occurrences (3):
| Input | Function | Config |
|---|
| rvp-reverse.ll | test_prev_v4i8 | -mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs |
| rvp-simd-32.ll | test_non_const_splat_i8 | -mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs |
| rvp-reverse.0fe498b94f.ll (mutant of rvp-reverse.ll) | test_prev_v4i8 | -mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs |
Generated 2026-10-15 08:05 UTC.