fallback: legalize: G_BITCAST <4 x s16>,<8 x s8>
| Run: | main-04ca53e65f-20261014-105623 |
| Kind: | fallback |
| Category: | legalize: G_BITCAST <4 x s16>,<8 x s8> |
| Occurrences: | 2 in 1 configs, 1 test files |
| Snippet from: | rvp-widening-convert.ll @test_pwcvth_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 i16> @test_pwcvth_v4i8(<4 x i8> %a) {
%shuffle = shufflevector <4 x i8> zeroinitializer, <4 x i8> %a, <8 x i32> <i32 0, i32 4, i32 1, i32 5, i32 2, i32 6, i32 3, i32 7>
%res = bitcast <8 x i8> %shuffle to <4 x i16>
ret <4 x i16> %res
}
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: %6:_(<4 x s16>) = G_BITCAST %3:_(<8 x s8>) (in function: test_pwcvth_v4i8)
warning: Instruction selection used fallback path for test_pwcvth_v4i8
Occurrences (2):
| Input | Function | Config |
|---|
| rvp-widening-convert.ll | test_pwcvth_v4i8 | -mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs |
| rvp-widening-convert.9bb5c6787c.ll (mutant of rvp-widening-convert.ll) | test_pwcvth_v4i8 | -mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs |
Generated 2026-10-15 08:05 UTC.