Add LLDB data formatters for Slang IR (#7828)

1 files changed, 179 insertions, 0 deletions

diff --git a/source/slang/slang_lldb.py b/source/slang/slang_lldb.py
new file mode 100644
index 000000000..c1213e830
--- /dev/null
+++ b/source/slang/slang_lldb.py
@@ -0,0 +1,179 @@
+"""
+This python script provides LLDB formatters for Slang IR types.
+To use it, add the following line to your ~/.lldbinit file:
+command script import /path/to/source/slang/slang_lldb.py
+"""
+
+import json
+
+import lldb
+
+
+class Children:
+    indices: dict[str, int]
+    values: list[lldb.SBValue]
+
+    def __init__(self):
+        self.indices = {}
+        self.values = []
+
+    def append(self, value: lldb.SBValue) -> None:
+        self.indices[value.name] = len(self.values)
+        self.values.append(value)
+
+    def __len__(self) -> int:
+        return len(self.values)
+
+    def get_index(self, name: str) -> int:
+        return self.indices[name]
+
+    def get_at_index(self, idx: int) -> lldb.SBValue:
+        return self.values[idx]
+
+
+def IRUse_summary(valobj: lldb.SBValue, dict) -> str:
+    val = valobj.GetNonSyntheticValue()
+    return val.GetChildMemberWithName("usedValue").deref.summary
+
+
+class IRInstListBase_synthetic(lldb.SBSyntheticValueProvider):
+    def __init__(self, valobj: lldb.SBValue, dict):
+        self.valobj = valobj
+
+    def num_children(self):
+        return len(self.children)
+
+    def get_child_index(self, name):
+        return self.children.get_index(name)
+
+    def get_child_at_index(self, idx):
+        return self.children.get_at_index(idx)
+
+    def update(self):
+        self.children = Children()
+        pointer = self.valobj.GetChildMemberWithName("first")
+        i = 0
+        while pointer.unsigned != 0:
+            child = pointer.deref
+            self.children.append(child.Clone(f"[{i}]"))
+            pointer = child.GetNonSyntheticValue().GetChildMemberWithName("next")
+            i += 1
+
+    def has_children(self):
+        return True
+
+
+class IRInst_synthetic(lldb.SBSyntheticValueProvider):
+    def __init__(self, valobj: lldb.SBValue, dict):
+        self.valobj = valobj
+
+    def num_children(self):
+        return len(self.children)
+
+    def get_child_index(self, name):
+        return self.children.get_index(name)
+
+    def get_child_at_index(self, idx):
+        return self.children.get_at_index(idx)
+
+    def update(self):
+        self.children = Children()
+        target = self.valobj.target
+        ty = self.valobj.type
+        op = self.valobj.GetChildMemberWithName("m_op")
+
+        # literal values
+        value: list[tuple[str, lldb.SBValue]] = []
+        match op.value:
+            case "kIROp_StringLit":
+                string_lit_t = target.FindFirstType("Slang::IRStringLit")
+                string_lit = self.valobj.Cast(string_lit_t)
+                val = string_lit.GetChildMemberWithName("value")
+                value = [("[value]", val.GetChildMemberWithName("stringVal"))]
+            case "kIROp_IntLit":
+                int_lit_t = target.FindFirstType("Slang::IRIntLit")
+                int_lit = self.valobj.Cast(int_lit_t)
+                val = int_lit.GetChildMemberWithName("value")
+                value = [("[value]", val.GetChildMemberWithName("intVal"))]
+
+        # operands
+        operands: list[tuple[str, lldb.SBValue]] = []
+        offset = ty.GetByteSize()
+        ir_use_t = target.FindFirstType("Slang::IRUse")
+        ir_use_size = ir_use_t.GetByteSize()
+        for index in range(self.valobj.GetChildMemberWithName("operandCount").unsigned):
+            name = f"[operand{index}]"
+            operand = self.valobj.CreateChildAtOffset(
+                name, offset + index * ir_use_size, ir_use_t
+            )
+            operands.append((name, operand))
+
+        for name, child in [
+            ("[op]", op),
+            ("[UID]", self.valobj.GetChildMemberWithName("_debugUID")),
+            (
+                "[type]",
+                self.valobj.GetChildMemberWithName("typeUse").GetChildMemberWithName(
+                    "usedValue"
+                ),
+            ),
+            # TODO: [exportName]
+            # TODO: [importName]
+            # TODO: [name]
+            *value,
+            *operands,
+            (
+                "[decorations/children]",
+                self.valobj.GetChildMemberWithName("m_decorationsAndChildren"),
+            ),
+            ("[parent]", self.valobj.GetChildMemberWithName("parent")),
+            # TODO: Traverse the linked list to show all uses next to
+            # each other, rather than pointing to the first one.
+            ("[uses]", self.valobj.GetChildMemberWithName("firstUse")),
+        ]:
+            self.children.append(child.Clone(name))
+
+    def has_children(self):
+        return True
+
+
+def IRInst_summary(valobj: lldb.SBValue, dict) -> str:
+    val = valobj.GetNonSyntheticValue()
+    op = val.GetChildMemberWithName("m_op")
+    return f"{{{op.value} {val.address_of.value}}}"
+
+
+def stringval_summary(valobj: lldb.SBValue) -> str:
+    val = valobj.GetNonSyntheticValue()
+    num_chars = val.GetChildMemberWithName("numChars").unsigned
+    chars = val.GetChildMemberWithName("chars").GetPointeeData(0, num_chars).uint8
+    return json.dumps("".join(chr(chars[i]) for i in range(num_chars)))
+
+
+def StringValue_summary(valobj: lldb.SBValue, dict) -> str:
+    return stringval_summary(valobj)
+
+
+def StringSliceValue_summary(valobj: lldb.SBValue, dict) -> str:
+    return stringval_summary(valobj)
+
+
+def __lldb_init_module(debugger: lldb.SBDebugger, internal_dict):
+    commands = [
+        # Slang::IRUse
+        "type summary add Slang::IRUse -F slang_lldb.IRUse_summary -w slang",
+        # Slang::IRInstListBase
+        "type synthetic add Slang::IRInstListBase -l slang_lldb.IRInstListBase_synthetic -w slang",
+        # Slang::IRInst
+        "type synthetic add Slang::IRInst -l slang_lldb.IRInst_synthetic -w slang",
+        "type summary add --expand Slang::IRInst -F slang_lldb.IRInst_summary -w slang",
+        # Slang::IRConstant::StringValue
+        "type summary add Slang::IRConstant::StringValue -F slang_lldb.StringValue_summary -w slang",
+        # Slang::IRConstant::StringSliceValue
+        "type summary add Slang::IRConstant::StringSliceValue -F slang_lldb.StringSliceValue_summary -w slang",
+        # Enable slang category
+        "type category enable slang",
+    ]
+
+    for c in commands:
+        debugger.HandleCommand(c)