Code that demonstrations elimination of redundant stores

store-migration.c

void multiply_add(int *accumulator, int multiplier, int addend) {
    *accumulator *= multiplier;
    *accumulator += addend;
}

store-migration_fgcse-sm_arm64.asm

// -fgcse-sm

multiply_add:
        ldr     w3, [x0]
        madd    w3, w3, w1, w2
        str     w3, [x0]
        ret

store-migration_fgcse-sm_x86-64.asm

# -fgcse-sm

multiply_add:
        imull   (%rdi), %esi
        addl    %edx, %esi
        movl    %esi, (%rdi)
        ret

store-migration_handcrafted.c

void optimized_multiply_add(int *accumulator, int multiplier, int addend) {
    int local_accumulator = *accumulator;
    local_accumulator *= multiplier;
    local_accumulator += addend;
    *accumulator = local_accumulator;
}

store-migration_Og_arm64.asm

multiply_add:
        ldr     w3, [x0]
        mul     w1, w3, w1
        str     w1, [x0]
        add     w1, w1, w2
        str     w1, [x0]
        ret

store-migration_Og_x86-64.asm

multiply_add:
        imull   (%rdi), %esi
        movl    %esi, (%rdi)
        addl    %edx, %esi
        movl    %esi, (%rdi)
        ret