[GlobalISel] Lower integer operations to libcalls

3 files changed, 22 insertions, 7 deletions

diff --git a/backend/include/rcc/CodeGen/GlobalISel/Legalizer.h b/backend/include/rcc/CodeGen/GlobalISel/Legalizer.h
index 358ed1a..2ba0012 100644
--- a/backend/include/rcc/CodeGen/GlobalISel/Legalizer.h
+++ b/backend/include/rcc/CodeGen/GlobalISel/Legalizer.h
@@ -6,6 +6,7 @@
 #include "rcc/CodeGen/CommandFlags.h"
 #include "rcc/CodeGen/GlobalISel/LegalizerInfo.h"
 #include "rcc/CodeGen/MachinePassManager.h"
+#include "rcc/CodeGen/TargetCallLowering.h"
 
 #include <memory>
 
@@ -13,12 +14,16 @@ namespace rcc {
 
 class Legalizer final : public MachineFunctionPass {
 public:
-  Legalizer(const LegalizerInfo *Info, OptimizationLevel Optimization)
-      : Info(Info), Optimization(Optimization) {}
-  Legalizer(const LegalizerInfo &Info, OptimizationLevel Optimization)
-      : Info(&Info), Optimization(Optimization) {}
-  Legalizer(std::unique_ptr<LegalizerInfo> Info, OptimizationLevel Optimization)
-      : OwnedInfo(std::move(Info)), Info(OwnedInfo.get()), Optimization(Optimization) {}
+  Legalizer(const LegalizerInfo *Info, OptimizationLevel Optimization,
+            LibcallLoweringInfo Libcalls = {})
+      : Info(Info), Optimization(Optimization), Libcalls(Libcalls) {}
+  Legalizer(const LegalizerInfo &Info, OptimizationLevel Optimization,
+            LibcallLoweringInfo Libcalls = {})
+      : Info(&Info), Optimization(Optimization), Libcalls(Libcalls) {}
+  Legalizer(std::unique_ptr<LegalizerInfo> Info, OptimizationLevel Optimization,
+            LibcallLoweringInfo Libcalls = {})
+      : OwnedInfo(std::move(Info)), Info(OwnedInfo.get()), Optimization(Optimization),
+        Libcalls(Libcalls) {}
 
   [[nodiscard]] const MachinePassContract &contract() const noexcept override;
   [[nodiscard]] Expected<MachinePassResult> run(MachineFunction &Function,
@@ -33,6 +38,7 @@ private:
   std::unique_ptr<LegalizerInfo> OwnedInfo;
   const LegalizerInfo *Info = nullptr;
   OptimizationLevel Optimization;
+  LibcallLoweringInfo Libcalls;
 };
 
 } // namespace rcc
diff --git a/backend/include/rcc/CodeGen/GlobalISel/LegalizerHelper.h b/backend/include/rcc/CodeGen/GlobalISel/LegalizerHelper.h
index 9ad66a2..39304ba 100644
--- a/backend/include/rcc/CodeGen/GlobalISel/LegalizerHelper.h
+++ b/backend/include/rcc/CodeGen/GlobalISel/LegalizerHelper.h
@@ -15,6 +15,7 @@ namespace rcc {
 class MachineFunction;
 class MachineInstr;
 class GISelChangeObserver;
+struct LibcallLoweringInfo;
 
 class LegalizerHelper final {
 public:
@@ -22,7 +23,8 @@ public:
   GISelChangeObserver &Observer;
 
   LegalizerHelper(MachineFunction &Function, const LegalizerInfo &Info,
-                  GISelChangeObserver &Observer, MachineIRBuilder &MIRBuilder);
+                  GISelChangeObserver &Observer, MachineIRBuilder &MIRBuilder,
+                  const LibcallLoweringInfo *Libcalls = nullptr);
 
   [[nodiscard]] Expected<void> legalize(MachineInstr &Instruction,
                                         const LegalizationDecision &Decision);
@@ -35,6 +37,7 @@ public:
   [[nodiscard]] Expected<void> lowerThreewayCompare(MachineInstr &Instruction);
   [[nodiscard]] Expected<void> lowerRotate(MachineInstr &Instruction);
   [[nodiscard]] Expected<void> lowerVAArg(MachineInstr &Instruction);
+  [[nodiscard]] Expected<void> libcall(MachineInstr &Instruction);
   [[nodiscard]] Expected<void> widenScalar(MachineInstr &Instruction, std::size_t TypeIndex,
                                            LowLevelType WideType);
   [[nodiscard]] Expected<void> widenScalarSrc(MachineInstr &Instruction, LowLevelType WideType,
@@ -118,6 +121,7 @@ private:
   MachineFunction &Function;
   MachineRegisterInfo &MRI;
   const LegalizerInfo &Info;
+  const LibcallLoweringInfo *Libcalls = nullptr;
 };
 
 } // namespace rcc
diff --git a/backend/include/rcc/CodeGen/TargetCallLowering.h b/backend/include/rcc/CodeGen/TargetCallLowering.h
index 21b5407..576ec39 100644
--- a/backend/include/rcc/CodeGen/TargetCallLowering.h
+++ b/backend/include/rcc/CodeGen/TargetCallLowering.h
@@ -402,6 +402,11 @@ public:
                                                 const CallLoweringPlan &Plan) const = 0;
 };
 
+struct LibcallLoweringInfo final {
+  const TargetCallLowering *CallLowering = nullptr;
+  CallingConventionID Convention;
+};
+
 } // namespace rcc
 
 #endif // RCC_CODEGEN_TARGETCALLLOWERING_H