; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 4 ; RUN: llc < %s -mtriple=riscv64 -mattr=+v -riscv-v-vector-bits-max=128 -verify-machineinstrs | FileCheck %s ; This showcases a miscompile that was fixed in #83107: ; - The memset will be type-legalized to a 512 bit store + 2 x 128 bit stores. ; - the load and store of q aliases the upper 128 bits store of p. ; - The aliasing 128 bit store will be between the chain of the scalar ; load/store: ; ; t54: ch = store<(store (s512) into %ir.p, align 1)> t0, ... ; t51: ch = store<(store (s128) into %ir.p + 64, align 1)> t0, ... ; ; t44: i64,ch = load<(load (s32) from %ir.q), sext from i32> t0, ... ; t50: ch = store<(store (s128) into %ir.p + 80, align 1)> t44:1, ... ; t46: ch = store<(store (s32) into %ir.q), trunc to i32> t50, ... ; ; Previously, the scalar load/store was incorrectly combined away: ; ; t54: ch = store<(store (s512) into %ir.p, align 1)> t0, ... ; t51: ch = store<(store (s128) into %ir.p + 64, align 1)> t0, ... ; ; // MISSING ; t50: ch = store<(store (s128) into %ir.p + 80, align 1)> t44:1, ... ; // MISSING ; ; - We need to compile with an exact VLEN so that we select an ISD::STORE node ; which triggers the combine ; - The miscompile doesn't happen if we use separate GEPs as we need the stores ; to share the same MachinePointerInfo define void @aliasing(ptr %p) { ; CHECK-LABEL: aliasing: ; CHECK: # %bb.0: ; CHECK-NEXT: lw a1, 84(a0) ; CHECK-NEXT: addi a2, a0, 80 ; CHECK-NEXT: vsetivli zero, 16, e8, m1, ta, ma ; CHECK-NEXT: vmv.v.i v8, 0 ; CHECK-NEXT: vs1r.v v8, (a2) ; CHECK-NEXT: addi a2, a0, 64 ; CHECK-NEXT: vs1r.v v8, (a2) ; CHECK-NEXT: vsetvli a2, zero, e8, m4, ta, ma ; CHECK-NEXT: vmv.v.i v8, 0 ; CHECK-NEXT: vs4r.v v8, (a0) ; CHECK-NEXT: sw a1, 84(a0) ; CHECK-NEXT: ret %q = getelementptr inbounds i8, ptr %p, i64 84 %tmp = load i32, ptr %q tail call void @llvm.memset.p0.i64(ptr %p, i8 0, i64 96, i1 false) store i32 %tmp, ptr %q ret void }