carbon-language/carbon-lang
1
0
Fork 0
mirror of https://github.com/carbon-language/carbon-lang.git synced 2026-10-04 22:02:52 +01:00
Code Issues Packages Projects Releases 10 Wiki Activity

Add the form ID to FormParamPattern (#6928)

Browse Source 
This enables some nice simplifications, and it's also a step toward a
broader restructuring of binding and parameter patterns.

Assisted-by: Gemini 3.1 Pro via Antigravity
This commit is contained in:
Geoff Romer
2026-03-20 01:08:38 +00:00
committed by GitHub
parent ce50f181f1
commit 8e5b358ec2
11 changed files with 65 additions and 88 deletions
Download Patch File Download Diff File Expand all files Collapse all files
toolchain/check/pattern_match.cpp
+38 -52
View File
@@ -231,12 +231,9 @@ static auto InsertHere(Context& context, SemIR::ExprRegionId region_id)
}
// Returns the kind of conversion to perform on the scrutinee when matching the
// given pattern. `form_kind` is the form of the pattern, if known; it only
// affects the behavior of `FormBindingPattern` and `FormParamPattern`,
// and it must be set in the `FormParamPattern` case.
static auto ConversionKindFor(
Context& context, SemIR::Inst pattern, MatchContext::WorkItem entry,
std::optional<SemIR::InstKind> form_kind = std::nullopt)
// given pattern.
static auto ConversionKindFor(Context& context, SemIR::Inst pattern,
MatchContext::WorkItem entry)
-> ConversionTarget::Kind {
CARBON_KIND_SWITCH(pattern) {
case SemIR::OutParamPattern::Kind:
@@ -252,15 +249,13 @@ static auto ConversionKindFor(
case SemIR::ValueParamPattern::Kind:
return ConversionTarget::Value;
case CARBON_KIND(SemIR::FormBindingPattern form_binding_pattern): {
if (!form_kind) {
auto form_id = context.entity_names()
.Get(form_binding_pattern.entity_name_id)
.form_id;
auto form_inst_id = context.constant_values().GetInstId(form_id);
form_kind = context.insts().Get(form_inst_id).kind();
}
auto form_id = context.entity_names()
.Get(form_binding_pattern.entity_name_id)
.form_id;
auto form_inst_id = context.constant_values().GetInstId(form_id);
auto form_inst = context.insts().Get(form_inst_id);
switch (*form_kind) {
switch (form_inst.kind()) {
case SemIR::InitForm::Kind:
context.TODO(entry.pattern_id, "Support local initializing forms");
[[fallthrough]];
@@ -272,12 +267,15 @@ static auto ConversionKindFor(
case SemIR::ValueForm::Kind:
return ConversionTarget::Value;
default:
CARBON_FATAL("Unexpected form kind {0}", form_kind);
CARBON_FATAL("Unexpected form {0}", form_inst);
}
}
case SemIR::FormParamPattern::Kind: {
CARBON_CHECK(form_kind);
switch (*form_kind) {
case CARBON_KIND(SemIR::FormParamPattern form_param_pattern): {
auto form_inst_id =
context.constant_values().GetInstId(form_param_pattern.form_id);
auto form_inst = context.insts().Get(form_inst_id);
switch (form_inst.kind()) {
case SemIR::InitForm::Kind:
return ConversionTarget::NoOp;
case SemIR::RefForm::Kind:
@@ -291,7 +289,7 @@ static auto ConversionKindFor(
case SemIR::ValueForm::Kind:
return ConversionTarget::Value;
default:
CARBON_FATAL("Unexpected form kind {0}", form_kind);
CARBON_FATAL("Unexpected form {0}", form_inst);
}
}
default:
@@ -346,13 +344,10 @@ auto MatchContext::DoEmitPatternMatch(Context& context,
}
// Returns the inst kind to use for the parameter corresponding to the given
// parameter pattern. If the pattern is a `FormParamPattern`, `form_kind`
// must be the pattern's form; otherwise it is ignored.
static auto ParamKindFor(
Context& context, SemIR::Inst param_pattern, MatchContext::WorkItem entry,
std::optional<SemIR::InstKind> form_kind = std::nullopt)
-> SemIR::InstKind {
switch (param_pattern.kind()) {
// parameter pattern.
static auto ParamKindFor(Context& context, SemIR::Inst param_pattern,
MatchContext::WorkItem entry) -> SemIR::InstKind {
CARBON_KIND_SWITCH(param_pattern) {
case SemIR::OutParamPattern::Kind:
return SemIR::OutParam::Kind;
case SemIR::RefParamPattern::Kind:
@@ -360,9 +355,11 @@ static auto ParamKindFor(
return SemIR::RefParam::Kind;
case SemIR::ValueParamPattern::Kind:
return SemIR::ValueParam::Kind;
case SemIR::FormParamPattern::Kind:
CARBON_CHECK(form_kind);
switch (*form_kind) {
case CARBON_KIND(SemIR::FormParamPattern form_param_pattern): {
auto form_inst_id =
context.constant_values().GetInstId(form_param_pattern.form_id);
auto form_inst = context.insts().Get(form_inst_id);
switch (form_inst.kind()) {
case SemIR::InitForm::Kind:
case SemIR::RefForm::Kind:
return SemIR::RefParam::Kind;
@@ -373,8 +370,9 @@ static auto ParamKindFor(
case SemIR::ValueForm::Kind:
return SemIR::ValueParam::Kind;
default:
CARBON_FATAL("Unexpected form kind {0}", form_kind);
CARBON_FATAL("Unexpected form {0}", form_inst);
}
}
default:
CARBON_FATAL("Unexpected param pattern kind: {0}", param_pattern);
}
@@ -383,26 +381,15 @@ static auto ParamKindFor(
auto MatchContext::DoEmitPatternMatch(Context& context,
SemIR::AnyParamPattern param_pattern,
WorkItem entry) -> void {
// If this is a FormParamPattern, determine its form.
std::optional<SemIR::InstKind> form_kind;
// If the form is initializing, match this as a `VarPattern` before matching
// it as a parameter pattern.
if (param_pattern.kind == SemIR::FormParamPattern::Kind) {
if (param_pattern.subpattern_id == SemIR::ErrorInst::InstId) {
form_kind = SemIR::ErrorInst::Kind;
} else {
auto binding_pattern = context.insts().GetAs<SemIR::FormBindingPattern>(
param_pattern.subpattern_id);
auto form_id =
context.entity_names().Get(binding_pattern.entity_name_id).form_id;
auto form_inst_id = context.constant_values().GetInstId(form_id);
form_kind = context.insts().Get(form_inst_id).kind();
// If the form is initializing, match this as a `VarPattern` before
// matching it as a parameter pattern.
if (form_kind == SemIR::InitForm::Kind) {
auto new_scrutinee_id =
DoEmitVarPatternMatchImpl(context, param_pattern.type_id, entry);
entry.scrutinee_id = new_scrutinee_id;
}
auto form_inst_id =
context.constant_values().GetInstId(param_pattern.form_id);
if (context.insts().Get(form_inst_id).kind() == SemIR::InitForm::Kind) {
auto new_scrutinee_id =
DoEmitVarPatternMatchImpl(context, param_pattern.type_id, entry);
entry.scrutinee_id = new_scrutinee_id;
}
}
@@ -418,8 +405,7 @@ auto MatchContext::DoEmitPatternMatch(Context& context,
context.sem_ir(), callee_specific_id_, entry.pattern_id));
call_args_.push_back(Convert(
context, SemIR::LocId(entry.scrutinee_id), entry.scrutinee_id,
{.kind =
ConversionKindFor(context, param_pattern, entry, form_kind),
{.kind = ConversionKindFor(context, param_pattern, entry),
.type_id = scrutinee_type_id}));
}
// Do not traverse farther, because the caller side of the pattern
@@ -428,7 +414,7 @@ auto MatchContext::DoEmitPatternMatch(Context& context,
}
case MatchKind::Callee: {
SemIR::AnyParam param = {
.kind = ParamKindFor(context, param_pattern, entry, form_kind),
.kind = ParamKindFor(context, param_pattern, entry),
.type_id =
ExtractScrutineeType(context.sem_ir(), param_pattern.type_id),
.index = SemIR::CallParamIndex(call_params_.size()),