bc: implement pass-by-reference code from upstream

function                                             old     new   delta
zxc_program_popResultAndCopyToVar                    298     493    +195
bc_vec_pushIndex                                       -      75     +75
zxc_vm_process                                       859     928     +69
xc_program_dereference                                 -      66     +66
bc_vec_npush                                           -      65     +65
zbc_num_s                                            239     249     +10
zxc_program_num                                     1024    1032      +8
zbc_num_divmod                                       150     156      +6
xc_program_search                                    143     146      +3
zxc_program_assign                                   392     389      -3
zdc_program_execStr                                  520     517      -3
xc_program_pushVar                                   198     195      -3
zxc_program_exec                                    4101    4092      -9
zbc_program_call                                     318     308     -10
zbc_func_insert                                      120     104     -16
zbc_parse_stmt_possibly_auto                        1460    1439     -21
bc_vec_push                                           53      12     -41
xc_parse_pushIndex                                    61      18     -43
------------------------------------------------------------------------------
(add/remove: 3/0 grow/shrink: 6/9 up/down: 497/-149)          Total: 348 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

2 files changed, 318 insertions, 0 deletions

diff --git a/testsuite/bc_references.bc b/testsuite/bc_references.bc
new file mode 100644
index 000000000..fc48c1a56
--- /dev/null
+++ b/testsuite/bc_references.bc
@@ -0,0 +1,106 @@
+define printarray(a[], len) {
+
+        auto i
+
+        for (i = 0; i < len; ++i) {
+                a[i]
+        }
+}
+
+define a2(a[], len) {
+
+        auto i
+
+        for (i = 0; i < len; ++i) {
+                a[i] = a[i] * a[i]
+        }
+
+        printarray(a[], len)
+}
+
+define a4(a__[], len) {
+
+        auto i
+
+        for (i = 0; i < len; ++i) {
+                a__[i] = a__[i] * a__[i]
+        }
+
+        printarray(a__[], len)
+}
+
+define a6(*a__[], len) {
+
+        auto i
+
+        for (i = 0; i < len; ++i) {
+                a__[i] = a__[i] * a__[i]
+        }
+
+        printarray(a__[], len)
+}
+
+define a1(*a[], len) {
+
+        auto i
+
+        for (i = 0; i < len; ++i) {
+                a[i] = i
+        }
+
+        a2(a[], len)
+
+        printarray(a[], len)
+}
+
+define a3(*a__[], len) {
+
+        auto i
+
+        for (i = 0; i < len; ++i) {
+                a__[i] = i
+        }
+
+        a4(a__[], len)
+
+        printarray(a__[], len)
+}
+
+define a5(*a__[], len) {
+
+        auto i
+
+        for (i = 0; i < len; ++i) {
+                a__[i] = i
+        }
+
+        a2(a__[], len)
+
+        printarray(a__[], len)
+}
+
+define a7(*a__[], len) {
+
+        auto i
+
+        for (i = 0; i < len; ++i) {
+                a__[i] = i
+        }
+
+        a6(a__[], len)
+
+        printarray(a__[], len)
+}
+
+len = 16
+
+a1(a[], len)
+printarray(a[], len)
+a3(a[], len)
+printarray(a[], len)
+a5(a[], len)
+printarray(a[], len)
+a7(a[], len)
+printarray(a[], len)
+
+halt
diff --git a/testsuite/bc_references_results.txt b/testsuite/bc_references_results.txt
new file mode 100644
index 000000000..564b54a3a
--- /dev/null
+++ b/testsuite/bc_references_results.txt
@@ -0,0 +1,212 @@
+0
+1
+4
+9
+16
+25
+36
+49
+64
+81
+100
+121
+144
+169
+196
+225
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+0
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+4
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+64
+81
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+144
+169
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+0