Special casing some VC++ traps.

src/alloy/backend/ivm/ivm_intcode.cc

@@ -309,8 +309,15 @@ int Translate_DEBUG_BREAK_TRUE(TranslationContext& ctx, Instr* i) {
 }
 
 uint32_t IntCode_TRAP(IntCodeState& ics, const IntCode* i) {
-  // 0x0FE00014 is a 'debug print' where r3 = buffer r4 = length
   // TODO(benvanik): post software interrupt to debugger.
+  switch (i->flags) {
+  case 20:
+    // 0x0FE00014 is a 'debug print' where r3 = buffer r4 = length
+    break;
+  case 22:
+    // Always trap?
+    break;
+  }
   __debugbreak();
   return IA_NEXT;
 }

src/alloy/backend/x64/x64_emitter.cc

@@ -219,10 +219,23 @@ void X64Emitter::DebugBreak() {
   db(0xCC);
 }
 
-void X64Emitter::Trap() {
+void X64Emitter::Trap(uint16_t trap_type) {
+  switch (trap_type) {
+  case 20:
     // 0x0FE00014 is a 'debug print' where r3 = buffer r4 = length
+    // TODO(benvanik): debug print at runtime.
+    break;
+  case 0:
+  case 22:
+    // Always trap?
     // TODO(benvanik): post software interrupt to debugger.
     db(0xCC);
+    break;
+  default:
+    XELOGW("Unknown trap type %d", trap_type);
+    db(0xCC);
+    break;
+  }
 }
 
 void X64Emitter::UnimplementedInstr(const hir::Instr* i) {

src/alloy/backend/x64/x64_emitter.h

@@ -117,7 +117,7 @@ public:
   void MarkSourceOffset(const hir::Instr* i);
 
   void DebugBreak();
-  void Trap();
+  void Trap(uint16_t trap_type = 0);
   void UnimplementedInstr(const hir::Instr* i);
   void UnimplementedExtern(const hir::Instr* i);
 

src/alloy/backend/x64/x64_sequences.cc

@@ -191,7 +191,7 @@ EMITTER_OPCODE_TABLE(
 // ============================================================================
 EMITTER(TRAP, MATCH(I<OPCODE_TRAP, VoidOp>)) {
   static void Emit(X64Emitter& e, const EmitArgType& i) {
-    e.Trap();
+    e.Trap(i.instr->flags);
   }
 };
 EMITTER_OPCODE_TABLE(
@@ -207,7 +207,7 @@ EMITTER(TRAP_TRUE_I8, MATCH(I<OPCODE_TRAP_TRUE, VoidOp, I8<>>)) {
     e.test(i.src1, i.src1);
     Xbyak::Label skip;
     e.jz(skip);
-    e.Trap();
+    e.Trap(i.instr->flags);
     e.L(skip);
   }
 };
@@ -216,7 +216,7 @@ EMITTER(TRAP_TRUE_I16, MATCH(I<OPCODE_TRAP_TRUE, VoidOp, I16<>>)) {
     e.test(i.src1, i.src1);
     Xbyak::Label skip;
     e.jz(skip);
-    e.Trap();
+    e.Trap(i.instr->flags);
     e.L(skip);
   }
 };
@@ -225,7 +225,7 @@ EMITTER(TRAP_TRUE_I32, MATCH(I<OPCODE_TRAP_TRUE, VoidOp, I32<>>)) {
     e.test(i.src1, i.src1);
     Xbyak::Label skip;
     e.jz(skip);
-    e.Trap();
+    e.Trap(i.instr->flags);
     e.L(skip);
   }
 };
@@ -234,7 +234,7 @@ EMITTER(TRAP_TRUE_I64, MATCH(I<OPCODE_TRAP_TRUE, VoidOp, I64<>>)) {
     e.test(i.src1, i.src1);
     Xbyak::Label skip;
     e.jz(skip);
-    e.Trap();
+    e.Trap(i.instr->flags);
     e.L(skip);
   }
 };
@@ -243,7 +243,7 @@ EMITTER(TRAP_TRUE_F32, MATCH(I<OPCODE_TRAP_TRUE, VoidOp, F32<>>)) {
     e.vptest(i.src1, i.src1);
     Xbyak::Label skip;
     e.jz(skip);
-    e.Trap();
+    e.Trap(i.instr->flags);
     e.L(skip);
   }
 };
@@ -252,7 +252,7 @@ EMITTER(TRAP_TRUE_F64, MATCH(I<OPCODE_TRAP_TRUE, VoidOp, F64<>>)) {
     e.vptest(i.src1, i.src1);
     Xbyak::Label skip;
     e.jz(skip);
-    e.Trap();
+    e.Trap(i.instr->flags);
     e.L(skip);
   }
 };

src/alloy/frontend/ppc/ppc_emit_control.cc

@@ -482,6 +482,12 @@ XEEMITTER(twi,          0x0C000000, D  )(PPCHIRBuilder& f, InstrData& i) {
   // if (a = EXTS(SI)) & TO[2] then TRAP
   // if (a <u EXTS(SI)) & TO[3] then TRAP
   // if (a >u EXTS(SI)) & TO[4] then TRAP
+  if (i.D.RA == 0 && i.D.RT == 0x1F) {
+    // This is a special trap. Probably.
+    uint16_t type = (uint16_t)XEEXTS16(i.D.DS);
+    f.Trap(type);
+    return 0;
+  }
   Value* ra = f.SignExtend(f.Truncate(
       f.LoadGPR(i.D.RA), INT32_TYPE), INT64_TYPE);
   Value* rb = f.LoadConstant(XEEXTS16(i.D.DS));

src/alloy/hir/hir_builder.cc

@@ -577,21 +577,21 @@ void HIRBuilder::DebugBreakTrue(Value* cond) {
   EndBlock();
 }
 
-void HIRBuilder::Trap() {
+void HIRBuilder::Trap(uint16_t trap_code) {
-  Instr* i = AppendInstr(OPCODE_TRAP_info, 0);
+  Instr* i = AppendInstr(OPCODE_TRAP_info, trap_code);
   i->src1.value = i->src2.value = i->src3.value = NULL;
   EndBlock();
 }
 
-void HIRBuilder::TrapTrue(Value* cond) {
+void HIRBuilder::TrapTrue(Value* cond, uint16_t trap_code) {
   if (cond->IsConstant()) {
     if (cond->IsConstantTrue()) {
-      Trap();
+      Trap(trap_code);
     }
     return;
   }
 
-  Instr* i = AppendInstr(OPCODE_TRAP_TRUE_info, 0);
+  Instr* i = AppendInstr(OPCODE_TRAP_TRUE_info, trap_code);
   i->set_src1(cond);
   i->src2.value = i->src3.value = NULL;
   EndBlock();

src/alloy/hir/hir_builder.h

@@ -71,8 +71,8 @@ public:
   void DebugBreak();
   void DebugBreakTrue(Value* cond);
 
-  void Trap();
+  void Trap(uint16_t trap_code = 0);
-  void TrapTrue(Value* cond);
+  void TrapTrue(Value* cond, uint16_t trap_code = 0);
 
   void Call(runtime::FunctionInfo* symbol_info, uint32_t call_flags = 0);
   void CallTrue(Value* cond, runtime::FunctionInfo* symbol_info,