fallback: legalize: G_STORE <2 x s1>,p0

Run:	explore-bc8218b282-20261015-075519
Kind:	fallback
Category:	legalize: G_STORE <2 x s1>,p0 NEW
Occurrences:	1570 in 863 configs, 342 test files
Snippet from:	align.35f82de67f.ll (mutant of align.ll) @foo via llvm-extract + llvm-reduce
Config:	`-mtriple=riscv32 -mattr=+c -verify-machineinstrs`
Local check:	reproduces at bc8218b282
Compiler Explorer:	https://godbolt.org/z/sTh3nvnnh (llc-assertions-trunk, checked 2026-10-15 08:04 UTC): G reproduces

Snippet:

define void @foo() {
entry:
  store <2 x i1> zeroinitializer, ptr null, align 1
  ret void
}

Compiler Explorer panes:

Pane	Options	Exit	Insts	stderr
GlobalISel	`-mtriple=riscv32 -mattr=+c -verify-machineinstrs -global-isel -global-isel-abort=2 -pass-remarks-missed=gisel.*`	0	2	remark: <unknown>:0:0: unable to legalize instruction: G_STORE %0:_(<2 x s1>), %2:_(p0) :: (store (<2 x s1>) into `ptr null`) (in function: foo) warning: Instruction selection used fallback path for foo
SelectionDAG (control)	`-mtriple=riscv32 -mattr=+c -verify-machineinstrs -global-isel=0`	0	2	-

Reproduce:

llc -mtriple=riscv32 -mattr=+c -verify-machineinstrs -global-isel -global-isel-abort=2 -pass-remarks-missed=gisel.* snippet.ll -o -
llc -mtriple=riscv32 -mattr=+c -verify-machineinstrs -global-isel=0 snippet.ll -o -

Local llc output:

remark: <unknown>:0:0: unable to legalize instruction: G_STORE %0:_(<2 x s1>), %2:_(p0) :: (store (<2 x s1>) into `ptr null`) (in function: foo)
warning: Instruction selection used fallback path for foo

Occurrences (1570) (first 50):

Input	Function	Config
abds.25f8f11ce8.ll (mutant of abds.ll)	abd_sub_i32	`-mtriple=riscv64`
abds.3e7b9ea675.ll (mutant of abds.ll)	abd_sub_i32	`-mtriple=riscv64 -mattr=+zbb`
abds.3ecc56a59a.ll (mutant of abds.ll)	abd_sub_i32	`-mtriple=riscv32`
abds.5f682b539a.ll (mutant of abds.ll)	abd_sub_i32	`-mtriple=riscv32 -mattr=+zbb`
abdu-neg.090651bbfb.ll (mutant of abdu-neg.ll)	abd_ext_i16_i32	`-mtriple=riscv64 -mattr=+zbb`
abdu-neg.3a70c52383.ll (mutant of abdu-neg.ll)	abd_ext_i16_i32	`-mtriple=riscv64`
abdu-neg.a8e37c9028.ll (mutant of abdu-neg.ll)	abd_ext_i16_i32	`-mtriple=riscv32 -mattr=+zbb`
abdu-neg.c3f68adddf.ll (mutant of abdu-neg.ll)	abd_ext_i16_i32	`-mtriple=riscv32`
add-before-shl.0e07a46225.ll (mutant of add-before-shl.ll)	add_large_const	`-mtriple=riscv64 -mattr=+c -verify-machineinstrs -M no-aliases`
add-before-shl.18e8de9cb1.ll (mutant of add-before-shl.ll)	add_large_const	`-mtriple=riscv64 -verify-machineinstrs -M no-aliases`
add-before-shl.3bd37a7662.ll (mutant of add-before-shl.ll)	add_large_const	`-mtriple=riscv32 -verify-machineinstrs -M no-aliases`
add-before-shl.41ea7dc431.ll (mutant of add-before-shl.ll)	add_large_const	`-mtriple=riscv64 -mattr=+zca -verify-machineinstrs -M no-aliases`
add-before-shl.9804799cf1.ll (mutant of add-before-shl.ll)	add_large_const	`-mtriple=riscv32 -mattr=+zca -verify-machineinstrs -M no-aliases`
add-before-shl.a7005a0962.ll (mutant of add-before-shl.ll)	add_large_const	`-mtriple=riscv32 -mattr=+c -verify-machineinstrs -M no-aliases`
add-imm.78d34010d8.ll (mutant of add-imm.ll)	add32_sext_accept	`-mtriple=riscv32 -verify-machineinstrs`
add-imm.8d8e523edf.ll (mutant of add-imm.ll)	add32_sext_accept	`-mtriple=riscv64 -verify-machineinstrs`
add_sext_shl_constant.008d2e5d00.ll (mutant of add_sext_shl_constant.ll)	add_shl_sext	`-mtriple=riscv64 -mattr=+xandesperf`
add_sext_shl_constant.3e14adca19.ll (mutant of add_sext_shl_constant.ll)	add_shl_sext	`-mtriple=riscv64`
add_sext_shl_constant.a3f9305a22.ll (mutant of add_sext_shl_constant.ll)	add_shl_sext	`-mtriple=riscv64 -mattr=+zba`
addc-adde-sube-subc.7c82319d68.ll (mutant of addc-adde-sube-subc.ll)	subc_sube	`-mtriple=riscv32 -verify-machineinstrs`
addcarry.14c720ddda.ll (mutant of addcarry.ll)	addcarry_2x32	`-mtriple=riscv32 -mattr=+m`
addimm-mulimm.120cfc1271.ll (mutant of addimm-mulimm.ll)	mulneg3000_add8990_c	`-mtriple=riscv64 -mattr=+m,+zba -verify-machineinstrs`
addimm-mulimm.c02453d8fc.ll (mutant of addimm-mulimm.ll)	mulneg3000_add8990_c	`-mtriple=riscv32 -mattr=+m,+zba -verify-machineinstrs`
addrspacecast.0b77f9389c.ll (mutant of addrspacecast.ll)	cast1	`-mtriple=riscv64 -verify-machineinstrs`
addrspacecast.1ce03716f9.ll (mutant of addrspacecast.ll)	cast1	`-mtriple=riscv32 -verify-machineinstrs`
aext-to-sext.84c59e61c8.ll (mutant of aext-to-sext.ll)	sext_phi_constants	`-mtriple=riscv64 -mattr=+m -verify-machineinstrs`
align-loops.aa48c8fe86.ll (mutant of align-loops.ll)	test	`-mtriple=riscv64`
align-loops.b23621e622.ll (mutant of align-loops.ll)	test	`-mtriple=riscv64 -align-loops=32`
align-loops.dc07f17f08.ll (mutant of align-loops.ll)	test	`-mtriple=riscv64 -align-loops=16`
align.35f82de67f.ll (mutant of align.ll)	foo	`-mtriple=riscv32 -mattr=+c -verify-machineinstrs`
align.a1423431b7.ll (mutant of align.ll)	foo	`-mtriple=riscv32 -verify-machineinstrs`
allow-check.eb3368ed92.ll (mutant of allow-check.ll)	test_ubsan	`-mtriple=riscv32 -fast-isel=0`
allow-check.ebab1da33b.ll (mutant of allow-check.ll)	test_ubsan	`-mtriple=riscv64 -fast-isel=0`
alu32.1cddb4e7a6.ll (mutant of alu32.ll)	ori	`-mtriple=riscv32 -verify-machineinstrs`
alu32.9c4bb9c982.ll (mutant of alu32.ll)	ori	`-mtriple=riscv64 -verify-machineinstrs`
analyze-branch.6051923832.ll (mutant of analyze-branch.ll)	test_bcc_fallthrough_nottaken	`-mtriple=riscv32 -verify-machineinstrs`
and-shl.9716f10ced.ll (mutant of and-shl.ll)	and_0x7ff_shl_2	`-mtriple=riscv32 -verify-machineinstrs`
and-shl.d44804229c.ll (mutant of and-shl.ll)	and_0x7ff_shl_2	`-mtriple=riscv64 -verify-machineinstrs`
andn-zext-lowmask.09294132f0.ll (mutant of andn-zext-lowmask.ll)	andn_zext_lowmask_i64_i16	`-mtriple=riscv32 -verify-machineinstrs`
andn-zext-lowmask.13d0e704a0.ll (mutant of andn-zext-lowmask.ll)	andn_zext_lowmask_i64_i16	`-mtriple=riscv32 -mattr=+zbb -verify-machineinstrs`
andn-zext-lowmask.814fba8027.ll (mutant of andn-zext-lowmask.ll)	andn_zext_lowmask_i64_i16	`-mtriple=riscv64 -mattr=+zbb -verify-machineinstrs`
andn-zext-lowmask.f1d728074d.ll (mutant of andn-zext-lowmask.ll)	andn_zext_lowmask_i64_i16	`-mtriple=riscv64 -verify-machineinstrs`
arith-with-overflow.8509ced85e.ll (mutant of arith-with-overflow.ll)	ssub	`-mtriple=riscv32 -verify-machineinstrs`
atomic-cmpxchg-branch-on-result.00d39c4b84.ll (mutant of atomic-cmpxchg-branch-on-result.ll)	cmpxchg_masked_and_branch1	`-mtriple=riscv32 -mattr=+a -verify-machineinstrs`
atomic-cmpxchg-branch-on-result.853fd173aa.ll (mutant of atomic-cmpxchg-branch-on-result.ll)	cmpxchg_masked_and_branch1	`-mtriple=riscv32 -mattr=+a,+zacas -verify-machineinstrs`
atomic-cmpxchg-branch-on-result.b82bc433c7.ll (mutant of atomic-cmpxchg-branch-on-result.ll)	cmpxchg_masked_and_branch1	`-mtriple=riscv64 -mattr=+a,+zacas,+zabha -verify-machineinstrs`
atomic-cmpxchg-branch-on-result.b983522bd9.ll (mutant of atomic-cmpxchg-branch-on-result.ll)	cmpxchg_masked_and_branch1	`-mtriple=riscv64 -mattr=+a -verify-machineinstrs`
atomic-cmpxchg-branch-on-result.ceeede5f5b.ll (mutant of atomic-cmpxchg-branch-on-result.ll)	cmpxchg_masked_and_branch1	`-mtriple=riscv64 -mattr=+a,+zacas -verify-machineinstrs`
atomic-rmw-sub.22055640b0.ll (mutant of atomic-rmw-sub.ll)	atomicrmw_sub_i64_constant	`-mtriple=riscv32 -verify-machineinstrs`
atomic-rmw-sub.251623f0d6.ll (mutant of atomic-rmw-sub.ll)	atomicrmw_sub_i64_constant	`-mtriple=riscv32 -mattr=+zalrsc -verify-machineinstrs`

Generated 2026-10-15 08:05 UTC.