Merge 'translate/insert: Implement INSERT OR REPLACE' from Preston Thorpe

This PR implements support for `INSERT OR REPLACE INTO t`.
For `OR IGNORE`, we currently rewrite this internally to an `ON CONFLICT
DO NOTHING`, and I was hopeful we could do this with OR REPLACE, however
it seems SQLite actually deletes the row and then proceeds to insert, so
we could not simply rewrite this to an `ON CONFLICT DO UPDATE SET
col=excluded.col`, as this would result in differing rowid's when
compared to SQLite.

Reviewed-by: Jussi Saurio <[email protected]>

Closes #3972

Author: PThorpe92

core/translate/emitter.rs

@@ -609,7 +609,7 @@ pub fn emit_fk_child_decrement_on_delete(
             // Parent MISSING, decrement is guarded by FkIfZero to avoid underflow
             program.preassign_label_to_next_insn(missing);
             program.emit_insn(Insn::Close { cursor_id: pcur });
-            emit_guarded_fk_decrement(program, done);
+            emit_guarded_fk_decrement(program, done, true);
             program.preassign_label_to_next_insn(done);
         } else {
             // Probe parent unique index
@@ -657,7 +657,7 @@ pub fn emit_fk_child_decrement_on_delete(
                 num_regs: n,
             });
             program.emit_insn(Insn::Close { cursor_id: icur });
-            emit_guarded_fk_decrement(program, ok);
+            emit_guarded_fk_decrement(program, ok, true);
             program.preassign_label_to_next_insn(ok);
             program.emit_insn(Insn::Close { cursor_id: icur });
         }

core/translate/fkeys.rs

@@ -14,14 +14,18 @@ use crate::{
 use std::{collections::HashSet, num::NonZeroUsize, sync::Arc};
 
 #[inline]
-pub fn emit_guarded_fk_decrement(program: &mut ProgramBuilder, label: BranchOffset) {
+pub fn emit_guarded_fk_decrement(
+    program: &mut ProgramBuilder,
+    label: BranchOffset,
+    deferred: bool,
+) {
     program.emit_insn(Insn::FkIfZero {
-        deferred: true,
+        deferred,
         target_pc: label,
     });
     program.emit_insn(Insn::FkCounter {
         increment_value: -1,
-        deferred: true,
+        deferred,
     });
 }
 
@@ -508,7 +512,7 @@ fn emit_fk_parent_key_probe(
             (true, ParentProbePass::New) => {
                 // Guard to avoid underflow if OLD pass didn't increment.
                 let skip = p.allocate_label();
-                emit_guarded_fk_decrement(p, skip);
+                emit_guarded_fk_decrement(p, skip, fk_ref.fk.deferred);
                 p.preassign_label_to_next_insn(skip);
             }
             // Immediate FK on NEW pass: nothing to cancel; do nothing.
@@ -676,7 +680,7 @@ pub fn emit_fk_child_update_counters(
                     program.preassign_label_to_next_insn(miss);
                     program.emit_insn(Insn::Close { cursor_id: pcur });
                     let skip = program.allocate_label();
-                    emit_guarded_fk_decrement(program, skip);
+                    emit_guarded_fk_decrement(program, skip, fk_ref.fk.deferred);
                     program.preassign_label_to_next_insn(skip);
 
                     program.preassign_label_to_next_insn(join);
@@ -703,7 +707,7 @@ pub fn emit_fk_child_update_counters(
                         |_p| Ok(()),
                         |p| {
                             let skip = p.allocate_label();
-                            emit_guarded_fk_decrement(p, skip);
+                            emit_guarded_fk_decrement(p, skip, fk_ref.fk.deferred);
                             p.preassign_label_to_next_insn(skip);
                             Ok(())
                         },