[JIT] Run the SimplificationPass/ConstantPropagationPass until there are no changes.

10 files changed, 348 insertions, 36 deletions

diff --git a/src/xenia/cpu/compiler/compiler_passes.h b/src/xenia/cpu/compiler/compiler_passes.h
index 6b81d1fb5..fc58ec710 100644
--- a/src/xenia/cpu/compiler/compiler_passes.h
+++ b/src/xenia/cpu/compiler/compiler_passes.h
@@ -10,6 +10,8 @@
 #ifndef XENIA_CPU_COMPILER_COMPILER_PASSES_H_
 #define XENIA_CPU_COMPILER_COMPILER_PASSES_H_
 
+#include "xenia/cpu/compiler/passes/conditional_group_pass.h"
+#include "xenia/cpu/compiler/passes/conditional_group_subpass.h"
 #include "xenia/cpu/compiler/passes/constant_propagation_pass.h"
 #include "xenia/cpu/compiler/passes/context_promotion_pass.h"
 #include "xenia/cpu/compiler/passes/control_flow_analysis_pass.h"
diff --git a/src/xenia/cpu/compiler/passes/conditional_group_pass.cc b/src/xenia/cpu/compiler/passes/conditional_group_pass.cc
new file mode 100644
index 000000000..ef84991e8
--- /dev/null
+++ b/src/xenia/cpu/compiler/passes/conditional_group_pass.cc
@@ -0,0 +1,85 @@
+/**
+ ******************************************************************************
+ * Xenia : Xbox 360 Emulator Research Project                                 *
+ ******************************************************************************
+ * Copyright 2013 Ben Vanik. All rights reserved.                             *
+ * Released under the BSD license - see LICENSE in the root for more details. *
+ ******************************************************************************
+ */
+
+#include "xenia/cpu/compiler/passes/conditional_group_pass.h"
+
+#include <gflags/gflags.h>
+
+#include "xenia/base/profiling.h"
+#include "xenia/cpu/compiler/compiler.h"
+#include "xenia/cpu/ppc/ppc_context.h"
+#include "xenia/cpu/processor.h"
+
+namespace xe {
+namespace cpu {
+namespace compiler {
+namespace passes {
+
+// TODO(benvanik): remove when enums redefined.
+using namespace xe::cpu::hir;
+
+using xe::cpu::hir::Block;
+using xe::cpu::hir::HIRBuilder;
+using xe::cpu::hir::Instr;
+using xe::cpu::hir::Value;
+
+ConditionalGroupPass::ConditionalGroupPass() : CompilerPass() {}
+
+ConditionalGroupPass::~ConditionalGroupPass() {}
+
+bool ConditionalGroupPass::Initialize(Compiler* compiler) {
+  if (!CompilerPass::Initialize(compiler)) {
+    return false;
+  }
+
+  for (size_t i = 0; i < passes_.size(); ++i) {
+    auto& pass = passes_[i];
+    if (!pass->Initialize(compiler)) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
+bool ConditionalGroupPass::Run(HIRBuilder* builder) {
+  bool dirty;
+  int loops = 0;
+  do {
+    assert_true(loops < 20);  // arbitrary number
+    dirty = false;
+    for (size_t i = 0; i < passes_.size(); ++i) {
+      scratch_arena()->Reset();
+      auto& pass = passes_[i];
+      auto subpass = dynamic_cast<ConditionalGroupSubpass*>(pass.get());
+      if (!subpass) {
+        if (!pass->Run(builder)) {
+          return false;
+        }
+      } else {
+        bool result = false;
+        if (!subpass->Run(builder, result)) {
+          return false;
+        }
+        dirty |= result;
+      }
+    }
+    loops++;
+  } while (dirty);
+  return true;
+}
+
+void ConditionalGroupPass::AddPass(std::unique_ptr<CompilerPass> pass) {
+  passes_.push_back(std::move(pass));
+}
+
+}  // namespace passes
+}  // namespace compiler
+}  // namespace cpu
+}  // namespace xe
diff --git a/src/xenia/cpu/compiler/passes/conditional_group_pass.h b/src/xenia/cpu/compiler/passes/conditional_group_pass.h
new file mode 100644
index 000000000..7421fe1b5
--- /dev/null
+++ b/src/xenia/cpu/compiler/passes/conditional_group_pass.h
@@ -0,0 +1,45 @@
+/**
+ ******************************************************************************
+ * Xenia : Xbox 360 Emulator Research Project                                 *
+ ******************************************************************************
+ * Copyright 2013 Ben Vanik. All rights reserved.                             *
+ * Released under the BSD license - see LICENSE in the root for more details. *
+ ******************************************************************************
+ */
+
+#ifndef XENIA_CPU_COMPILER_PASSES_CONDITIONAL_GROUP_PASS_H_
+#define XENIA_CPU_COMPILER_PASSES_CONDITIONAL_GROUP_PASS_H_
+
+#include <cmath>
+#include <vector>
+
+#include "xenia/base/platform.h"
+#include "xenia/cpu/compiler/compiler_pass.h"
+#include "xenia/cpu/compiler/passes/conditional_group_subpass.h"
+
+namespace xe {
+namespace cpu {
+namespace compiler {
+namespace passes {
+
+class ConditionalGroupPass : public CompilerPass {
+ public:
+  ConditionalGroupPass();
+  virtual ~ConditionalGroupPass() override;
+
+  bool Initialize(Compiler* compiler) override;
+
+  bool Run(hir::HIRBuilder* builder) override;
+
+  void AddPass(std::unique_ptr<CompilerPass> pass);
+
+ private:
+  std::vector<std::unique_ptr<CompilerPass>> passes_;
+};
+
+}  // namespace passes
+}  // namespace compiler
+}  // namespace cpu
+}  // namespace xe
+
+#endif  // XENIA_CPU_COMPILER_PASSES_CONDITIONAL_GROUP_PASS_H_
diff --git a/src/xenia/cpu/compiler/passes/conditional_group_subpass.cc b/src/xenia/cpu/compiler/passes/conditional_group_subpass.cc
new file mode 100644
index 000000000..39780e2f5
--- /dev/null
+++ b/src/xenia/cpu/compiler/passes/conditional_group_subpass.cc
@@ -0,0 +1,26 @@
+/**
+ ******************************************************************************
+ * Xenia : Xbox 360 Emulator Research Project                                 *
+ ******************************************************************************
+ * Copyright 2013 Ben Vanik. All rights reserved.                             *
+ * Released under the BSD license - see LICENSE in the root for more details. *
+ ******************************************************************************
+ */
+
+#include "xenia/cpu/compiler/passes/conditional_group_subpass.h"
+
+#include "xenia/cpu/compiler/compiler.h"
+
+namespace xe {
+namespace cpu {
+namespace compiler {
+namespace passes {
+
+ConditionalGroupSubpass::ConditionalGroupSubpass() : CompilerPass() {}
+
+ConditionalGroupSubpass::~ConditionalGroupSubpass() = default;
+
+}  // namespace passes
+}  // namespace compiler
+}  // namespace cpu
+}  // namespace xe
diff --git a/src/xenia/cpu/compiler/passes/conditional_group_subpass.h b/src/xenia/cpu/compiler/passes/conditional_group_subpass.h
new file mode 100644
index 000000000..f62c50ed3
--- /dev/null
+++ b/src/xenia/cpu/compiler/passes/conditional_group_subpass.h
@@ -0,0 +1,47 @@
+/**
+ ******************************************************************************
+ * Xenia : Xbox 360 Emulator Research Project                                 *
+ ******************************************************************************
+ * Copyright 2013 Ben Vanik. All rights reserved.                             *
+ * Released under the BSD license - see LICENSE in the root for more details. *
+ ******************************************************************************
+ */
+
+#ifndef XENIA_CPU_COMPILER_PASSES_CONDITIONAL_GROUP_SUBPASS_H_
+#define XENIA_CPU_COMPILER_PASSES_CONDITIONAL_GROUP_SUBPASS_H_
+
+#include "xenia/base/arena.h"
+#include "xenia/cpu/compiler/compiler_pass.h"
+#include "xenia/cpu/hir/hir_builder.h"
+
+namespace xe {
+namespace cpu {
+class Processor;
+}  // namespace cpu
+}  // namespace xe
+
+namespace xe {
+namespace cpu {
+namespace compiler {
+class Compiler;
+namespace passes {
+
+class ConditionalGroupSubpass : public CompilerPass {
+ public:
+  ConditionalGroupSubpass();
+  virtual ~ConditionalGroupSubpass();
+
+  bool Run(hir::HIRBuilder* builder) override {
+    bool dummy;
+    return Run(builder, dummy);
+  }
+
+  virtual bool Run(hir::HIRBuilder* builder, bool& result) = 0;
+};
+
+}  // namespace passes
+}  // namespace compiler
+}  // namespace cpu
+}  // namespace xe
+
+#endif  // XENIA_CPU_COMPILER_PASSES_CONDITIONAL_GROUP_SUBPASS_H_
diff --git a/src/xenia/cpu/compiler/passes/constant_propagation_pass.cc b/src/xenia/cpu/compiler/passes/constant_propagation_pass.cc
index 3db8e99d6..3a399cefd 100644
--- a/src/xenia/cpu/compiler/passes/constant_propagation_pass.cc
+++ b/src/xenia/cpu/compiler/passes/constant_propagation_pass.cc
@@ -31,11 +31,12 @@ using xe::cpu::hir::HIRBuilder;
 using xe::cpu::hir::TypeName;
 using xe::cpu::hir::Value;
 
-ConstantPropagationPass::ConstantPropagationPass() : CompilerPass() {}
+ConstantPropagationPass::ConstantPropagationPass()
+    : ConditionalGroupSubpass() {}
 
 ConstantPropagationPass::~ConstantPropagationPass() {}
 
-bool ConstantPropagationPass::Run(HIRBuilder* builder) {
+bool ConstantPropagationPass::Run(HIRBuilder* builder, bool& result) {
   // Once ContextPromotion has run there will likely be a whole slew of
   // constants that can be pushed through the function.
   // Example:
@@ -63,6 +64,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
   //   v1 = 19
   //   v2 = 0
 
+  result = false;
   auto block = builder->first_block();
   while (block) {
     auto i = block->instr_head;
@@ -76,6 +78,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             } else {
               i->Remove();
             }
+            result = true;
           }
           break;
 
@@ -86,6 +89,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             } else {
               i->Remove();
             }
+            result = true;
           }
           break;
 
@@ -98,6 +102,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             } else {
               i->Remove();
             }
+            result = true;
           }
           break;
         case OPCODE_CALL_INDIRECT:
@@ -109,6 +114,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             }
             i->Replace(&OPCODE_CALL_info, i->flags);
             i->src1.symbol = function;
+            result = true;
           }
           break;
         case OPCODE_CALL_INDIRECT_TRUE:
@@ -120,6 +126,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             } else {
               i->Remove();
             }
+            result = true;
           }
           break;
 
@@ -132,6 +139,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             } else {
               i->Remove();
             }
+            result = true;
           }
           break;
         case OPCODE_BRANCH_FALSE:
@@ -143,6 +151,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             } else {
               i->Remove();
             }
+            result = true;
           }
           break;
 
@@ -152,6 +161,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Cast(target_type);
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_CONVERT:
@@ -160,6 +170,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Convert(target_type, RoundMode(i->flags));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_ROUND:
@@ -167,6 +178,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Round(RoundMode(i->flags));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_ZERO_EXTEND:
@@ -175,6 +187,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->ZeroExtend(target_type);
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_SIGN_EXTEND:
@@ -183,6 +196,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->SignExtend(target_type);
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_TRUNCATE:
@@ -191,6 +205,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Truncate(target_type);
             i->Remove();
+            result = true;
           }
           break;
 
@@ -210,6 +225,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
               i->Replace(&OPCODE_LOAD_MMIO_info, 0);
               i->src1.offset = reinterpret_cast<uint64_t>(mmio_range);
               i->src2.offset = address;
+              result = true;
             } else {
               auto heap = memory->LookupHeap(address);
               uint32_t protect;
@@ -222,18 +238,22 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
                   case INT8_TYPE:
                     v->set_constant(xe::load<uint8_t>(host_addr));
                     i->Remove();
+                    result = true;
                     break;
                   case INT16_TYPE:
                     v->set_constant(xe::load<uint16_t>(host_addr));
                     i->Remove();
+                    result = true;
                     break;
                   case INT32_TYPE:
                     v->set_constant(xe::load<uint32_t>(host_addr));
                     i->Remove();
+                    result = true;
                     break;
                   case INT64_TYPE:
                     v->set_constant(xe::load<uint64_t>(host_addr));
                     i->Remove();
+                    result = true;
                     break;
                   case VEC128_TYPE:
                     vec128_t val;
@@ -241,6 +261,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
                     val.high = xe::load<uint64_t>(host_addr + 8);
                     v->set_constant(val);
                     i->Remove();
+                    result = true;
                     break;
                   default:
                     assert_unhandled_case(v->type);
@@ -270,6 +291,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
               i->src1.offset = reinterpret_cast<uint64_t>(mmio_range);
               i->src2.offset = address;
               i->set_src3(value);
+              result = true;
             }
           }
           break;
@@ -281,10 +303,12 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
                 auto src2 = i->src2.value;
                 i->Replace(&OPCODE_ASSIGN_info, 0);
                 i->set_src1(src2);
+                result = true;
               } else if (i->src1.value->IsConstantFalse()) {
                 auto src3 = i->src3.value;
                 i->Replace(&OPCODE_ASSIGN_info, 0);
                 i->set_src1(src3);
+                result = true;
               } else if (i->src2.value->IsConstant() &&
                          i->src3.value->IsConstant()) {
                 // TODO: Select
@@ -305,6 +329,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
               v->set_constant(uint8_t(0));
             }
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_IS_FALSE:
@@ -315,6 +340,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
               v->set_constant(uint8_t(0));
             }
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_IS_NAN:
@@ -329,6 +355,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
               v->set_constant(uint8_t(0));
             }
             i->Remove();
+            result = true;
           }
           break;
 
@@ -338,6 +365,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             bool value = i->src1.value->IsConstantEQ(i->src2.value);
             i->dest->set_constant(uint8_t(value));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_COMPARE_NE:
@@ -345,6 +373,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             bool value = i->src1.value->IsConstantNE(i->src2.value);
             i->dest->set_constant(uint8_t(value));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_COMPARE_SLT:
@@ -352,6 +381,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             bool value = i->src1.value->IsConstantSLT(i->src2.value);
             i->dest->set_constant(uint8_t(value));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_COMPARE_SLE:
@@ -359,6 +389,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             bool value = i->src1.value->IsConstantSLE(i->src2.value);
             i->dest->set_constant(uint8_t(value));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_COMPARE_SGT:
@@ -366,6 +397,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             bool value = i->src1.value->IsConstantSGT(i->src2.value);
             i->dest->set_constant(uint8_t(value));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_COMPARE_SGE:
@@ -373,6 +405,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             bool value = i->src1.value->IsConstantSGE(i->src2.value);
             i->dest->set_constant(uint8_t(value));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_COMPARE_ULT:
@@ -380,6 +413,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             bool value = i->src1.value->IsConstantULT(i->src2.value);
             i->dest->set_constant(uint8_t(value));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_COMPARE_ULE:
@@ -387,6 +421,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             bool value = i->src1.value->IsConstantULE(i->src2.value);
             i->dest->set_constant(uint8_t(value));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_COMPARE_UGT:
@@ -394,6 +429,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             bool value = i->src1.value->IsConstantUGT(i->src2.value);
             i->dest->set_constant(uint8_t(value));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_COMPARE_UGE:
@@ -401,6 +437,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             bool value = i->src1.value->IsConstantUGE(i->src2.value);
             i->dest->set_constant(uint8_t(value));
             i->Remove();
+            result = true;
           }
           break;
 
@@ -413,6 +450,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Add(i->src2.value);
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_ADD_CARRY:
@@ -433,6 +471,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
                 i->set_src1(ca);
               }
             }
+            result = true;
           }
           break;
         case OPCODE_SUB:
@@ -440,6 +479,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Sub(i->src2.value);
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_MUL:
@@ -447,6 +487,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Mul(i->src2.value);
             i->Remove();
+            result = true;
           } else if (i->src1.value->IsConstant() ||
                      i->src2.value->IsConstant()) {
             // Reorder the sources to make things simpler.
@@ -460,12 +501,14 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             if (s2->type != VEC128_TYPE && s2->IsConstantOne()) {
               i->Replace(&OPCODE_ASSIGN_info, 0);
               i->set_src1(s1);
+              result = true;
             } else if (s2->type == VEC128_TYPE) {
               auto& c = s2->constant;
               if (c.v128.f32[0] == 1.f && c.v128.f32[1] == 1.f &&
                   c.v128.f32[2] == 1.f && c.v128.f32[3] == 1.f) {
                 i->Replace(&OPCODE_ASSIGN_info, 0);
                 i->set_src1(s1);
+                result = true;
               }
             }
           }
@@ -475,6 +518,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->MulHi(i->src2.value, (i->flags & ARITHMETIC_UNSIGNED) != 0);
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_DIV:
@@ -482,6 +526,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Div(i->src2.value, (i->flags & ARITHMETIC_UNSIGNED) != 0);
             i->Remove();
+            result = true;
           } else if (i->src2.value->IsConstant()) {
             // Division by one = no-op.
             Value* src1 = i->src1.value;
@@ -489,12 +534,14 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
                 i->src2.value->IsConstantOne()) {
               i->Replace(&OPCODE_ASSIGN_info, 0);
               i->set_src1(src1);
+              result = true;
             } else if (i->src2.value->type == VEC128_TYPE) {
               auto& c = i->src2.value->constant;
               if (c.v128.f32[0] == 1.f && c.v128.f32[1] == 1.f &&
                   c.v128.f32[2] == 1.f && c.v128.f32[3] == 1.f) {
                 i->Replace(&OPCODE_ASSIGN_info, 0);
                 i->set_src1(src1);
+                result = true;
               }
             }
           }
@@ -505,6 +552,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
               v->set_from(i->src1.value);
               Value::MulAdd(v, i->src1.value, i->src2.value, i->src3.value);
               i->Remove();
+              result = true;
             } else {
               // Multiply part is constant.
               Value* mul = builder->AllocValue();
@@ -515,6 +563,8 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
               i->Replace(&OPCODE_ADD_info, 0);
               i->set_src1(mul);
               i->set_src2(add);
+
+              result = true;
             }
           }
           break;
@@ -525,6 +575,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
               v->set_from(i->src1.value);
               Value::MulSub(v, i->src1.value, i->src2.value, i->src3.value);
               i->Remove();
+              result = true;
             } else {
               // Multiply part is constant.
               Value* mul = builder->AllocValue();
@@ -535,6 +586,8 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
               i->Replace(&OPCODE_SUB_info, 0);
               i->set_src1(mul);
               i->set_src2(add);
+
+              result = true;
             }
           }
           break;
@@ -543,6 +596,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Max(i->src2.value);
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_NEG:
@@ -550,6 +604,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Neg();
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_ABS:
@@ -557,6 +612,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Abs();
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_SQRT:
@@ -564,6 +620,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Sqrt();
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_RSQRT:
@@ -571,6 +628,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->RSqrt();
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_RECIP:
@@ -578,6 +636,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Recip();
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_AND:
@@ -585,6 +644,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->And(i->src2.value);
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_OR:
@@ -592,6 +652,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Or(i->src2.value);
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_XOR:
@@ -599,11 +660,13 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Xor(i->src2.value);
             i->Remove();
+            result = true;
           } else if (!i->src1.value->IsConstant() &&
                      !i->src2.value->IsConstant() &&
                      i->src1.value == i->src2.value) {
             v->set_zero(v->type);
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_NOT:
@@ -611,6 +674,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Not();
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_SHL:
@@ -618,10 +682,12 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Shl(i->src2.value);
             i->Remove();
+            result = true;
           } else if (i->src2.value->IsConstantZero()) {
             auto src1 = i->src1.value;
             i->Replace(&OPCODE_ASSIGN_info, 0);
             i->set_src1(src1);
+            result = true;
           }
           break;
         case OPCODE_SHR:
@@ -629,10 +695,12 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Shr(i->src2.value);
             i->Remove();
+            result = true;
           } else if (i->src2.value->IsConstantZero()) {
             auto src1 = i->src1.value;
             i->Replace(&OPCODE_ASSIGN_info, 0);
             i->set_src1(src1);
+            result = true;
           }
           break;
         case OPCODE_SHA:
@@ -640,6 +708,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->Sha(i->src2.value);
             i->Remove();
+            result = true;
           }
           break;
         // TODO(benvanik): ROTATE_LEFT
@@ -648,6 +717,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->ByteSwap();
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_CNTLZ:
@@ -655,6 +725,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_zero(v->type);
             v->CountLeadingZeros(i->src1.value);
             i->Remove();
+            result = true;
           }
           break;
         // TODO(benvanik): INSERT/EXTRACT
@@ -664,6 +735,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_zero(v->type);
             v->Extract(i->src1.value, i->src2.value);
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_SPLAT:
@@ -671,6 +743,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_zero(v->type);
             v->Splat(i->src1.value);
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_VECTOR_COMPARE_EQ:
@@ -678,6 +751,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->VectorCompareEQ(i->src2.value, hir::TypeName(i->flags));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_VECTOR_COMPARE_SGT:
@@ -685,6 +759,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->VectorCompareSGT(i->src2.value, hir::TypeName(i->flags));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_VECTOR_COMPARE_SGE:
@@ -692,6 +767,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->VectorCompareSGE(i->src2.value, hir::TypeName(i->flags));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_VECTOR_COMPARE_UGT:
@@ -699,6 +775,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->VectorCompareUGT(i->src2.value, hir::TypeName(i->flags));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_VECTOR_COMPARE_UGE:
@@ -706,6 +783,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->VectorCompareUGE(i->src2.value, hir::TypeName(i->flags));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_VECTOR_CONVERT_F2I:
@@ -714,6 +792,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->VectorConvertF2I(i->src1.value,
                                 !!(i->flags & ARITHMETIC_UNSIGNED));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_VECTOR_CONVERT_I2F:
@@ -722,6 +801,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->VectorConvertI2F(i->src1.value,
                                 !!(i->flags & ARITHMETIC_UNSIGNED));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_VECTOR_SHL:
@@ -729,6 +809,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->VectorShl(i->src2.value, hir::TypeName(i->flags));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_VECTOR_SHR:
@@ -736,6 +817,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->VectorShr(i->src2.value, hir::TypeName(i->flags));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_VECTOR_ROTATE_LEFT:
@@ -743,6 +825,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->VectorRol(i->src2.value, hir::TypeName(i->flags));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_VECTOR_ADD:
@@ -753,6 +836,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
                          !!(arith_flags & ARITHMETIC_UNSIGNED),
                          !!(arith_flags & ARITHMETIC_SATURATE));
             i->Remove();
+            result = true;
           }
           break;
         case OPCODE_VECTOR_SUB:
@@ -763,6 +847,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
                          !!(arith_flags & ARITHMETIC_UNSIGNED),
                          !!(arith_flags & ARITHMETIC_SATURATE));
             i->Remove();
+            result = true;
           }
           break;
 
@@ -771,6 +856,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->DotProduct3(i->src2.value);
             i->Remove();
+            result = true;
           }
           break;
 
@@ -779,6 +865,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
             v->set_from(i->src1.value);
             v->DotProduct4(i->src2.value);
             i->Remove();
+            result = true;
           }
           break;
 
@@ -790,6 +877,7 @@ bool ConstantPropagationPass::Run(HIRBuilder* builder) {
                              !!(arith_flags & ARITHMETIC_UNSIGNED),
                              !!(arith_flags & ARITHMETIC_SATURATE));
             i->Remove();
+            result = true;
           }
           break;
 
diff --git a/src/xenia/cpu/compiler/passes/constant_propagation_pass.h b/src/xenia/cpu/compiler/passes/constant_propagation_pass.h
index 021bdc981..08bd25b4a 100644
--- a/src/xenia/cpu/compiler/passes/constant_propagation_pass.h
+++ b/src/xenia/cpu/compiler/passes/constant_propagation_pass.h
@@ -10,19 +10,19 @@
 #ifndef XENIA_CPU_COMPILER_PASSES_CONSTANT_PROPAGATION_PASS_H_
 #define XENIA_CPU_COMPILER_PASSES_CONSTANT_PROPAGATION_PASS_H_
 
-#include "xenia/cpu/compiler/compiler_pass.h"
+#include "xenia/cpu/compiler/passes/conditional_group_subpass.h"
 
 namespace xe {
 namespace cpu {
 namespace compiler {
 namespace passes {
 
-class ConstantPropagationPass : public CompilerPass {
+class ConstantPropagationPass : public ConditionalGroupSubpass {
  public:
   ConstantPropagationPass();
   ~ConstantPropagationPass() override;
 
-  bool Run(hir::HIRBuilder* builder) override;
+  bool Run(hir::HIRBuilder* builder, bool& result) override;
 
  private:
 };
diff --git a/src/xenia/cpu/compiler/passes/simplification_pass.cc b/src/xenia/cpu/compiler/passes/simplification_pass.cc
index 3278ab7c6..3569887a4 100644
--- a/src/xenia/cpu/compiler/passes/simplification_pass.cc
+++ b/src/xenia/cpu/compiler/passes/simplification_pass.cc
@@ -23,17 +23,18 @@ using xe::cpu::hir::HIRBuilder;
 using xe::cpu::hir::Instr;
 using xe::cpu::hir::Value;
 
-SimplificationPass::SimplificationPass() : CompilerPass() {}
+SimplificationPass::SimplificationPass() : ConditionalGroupSubpass() {}
 
 SimplificationPass::~SimplificationPass() {}
 
-bool SimplificationPass::Run(HIRBuilder* builder) {
-  EliminateConversions(builder);
-  SimplifyAssignments(builder);
+bool SimplificationPass::Run(HIRBuilder* builder, bool& result) {
+  result = false;
+  result |= EliminateConversions(builder);
+  result |= SimplifyAssignments(builder);
   return true;
 }
 
-void SimplificationPass::EliminateConversions(HIRBuilder* builder) {
+bool SimplificationPass::EliminateConversions(HIRBuilder* builder) {
   // First, we check for truncates/extensions that can be skipped.
   // This generates some assignments which then the second step will clean up.
   // Both zero/sign extends can be skipped:
@@ -43,6 +44,7 @@ void SimplificationPass::EliminateConversions(HIRBuilder* builder) {
   //   v1.i64 = zero/sign_extend v0.i32 (may be dead code removed later)
   //   v2.i32 = v0.i32
 
+  bool result = false;
   auto block = builder->first_block();
   while (block) {
     auto i = block->instr_head;
@@ -51,20 +53,21 @@ void SimplificationPass::EliminateConversions(HIRBuilder* builder) {
       // back to definition).
       if (i->opcode == &OPCODE_TRUNCATE_info) {
         // Matches zero/sign_extend + truncate.
-        CheckTruncate(i);
+        result |= CheckTruncate(i);
       } else if (i->opcode == &OPCODE_BYTE_SWAP_info) {
         // Matches byte swap + byte swap.
         // This is pretty rare within the same basic block, but is in the
         // memcpy hot path and (probably) worth it. Maybe.
-        CheckByteSwap(i);
+        result |= CheckByteSwap(i);
       }
       i = i->next;
     }
     block = block->next;
   }
+  return result;
 }
 
-void SimplificationPass::CheckTruncate(Instr* i) {
+bool SimplificationPass::CheckTruncate(Instr* i) {
   // Walk backward up src's chain looking for an extend. We may have
   // assigns, so skip those.
   auto src = i->src1.value;
@@ -80,6 +83,7 @@ void SimplificationPass::CheckTruncate(Instr* i) {
         // Types match, use original by turning this into an assign.
         i->Replace(&OPCODE_ASSIGN_info, 0);
         i->set_src1(def->src1.value);
+        return true;
       }
     } else if (def->opcode == &OPCODE_ZERO_EXTEND_info) {
       // Value comes from a zero extend.
@@ -87,12 +91,14 @@ void SimplificationPass::CheckTruncate(Instr* i) {
         // Types match, use original by turning this into an assign.
         i->Replace(&OPCODE_ASSIGN_info, 0);
         i->set_src1(def->src1.value);
+        return true;
       }
     }
   }
+  return false;
 }
 
-void SimplificationPass::CheckByteSwap(Instr* i) {
+bool SimplificationPass::CheckByteSwap(Instr* i) {
   // Walk backward up src's chain looking for a byte swap. We may have
   // assigns, so skip those.
   auto src = i->src1.value;
@@ -107,11 +113,13 @@ void SimplificationPass::CheckByteSwap(Instr* i) {
       // Types match, use original by turning this into an assign.
       i->Replace(&OPCODE_ASSIGN_info, 0);
       i->set_src1(def->src1.value);
+      return true;
     }
   }
+  return false;
 }
 
-void SimplificationPass::SimplifyAssignments(HIRBuilder* builder) {
+bool SimplificationPass::SimplifyAssignments(HIRBuilder* builder) {
   // Run over the instructions and rename assigned variables:
   //   v1 = v0
   //   v2 = v1
@@ -129,27 +137,35 @@ void SimplificationPass::SimplifyAssignments(HIRBuilder* builder) {
   // of that instr. Because we may have chains, we do this recursively until
   // we find a non-assign def.
 
+  bool result = false;
   auto block = builder->first_block();
   while (block) {
     auto i = block->instr_head;
     while (i) {
       uint32_t signature = i->opcode->signature;
       if (GET_OPCODE_SIG_TYPE_SRC1(signature) == OPCODE_SIG_TYPE_V) {
-        i->set_src1(CheckValue(i->src1.value));
+        bool modified = false;
+        i->set_src1(CheckValue(i->src1.value, modified));
+        result |= modified;
       }
       if (GET_OPCODE_SIG_TYPE_SRC2(signature) == OPCODE_SIG_TYPE_V) {
-        i->set_src2(CheckValue(i->src2.value));
+        bool modified = false;
+        i->set_src2(CheckValue(i->src2.value, modified));
+        result |= modified;
       }
       if (GET_OPCODE_SIG_TYPE_SRC3(signature) == OPCODE_SIG_TYPE_V) {
-        i->set_src3(CheckValue(i->src3.value));
+        bool modified = false;
+        i->set_src3(CheckValue(i->src3.value, modified));
+        result |= modified;
       }
       i = i->next;
     }
     block = block->next;
   }
+  return result;
 }
 
-Value* SimplificationPass::CheckValue(Value* value) {
+Value* SimplificationPass::CheckValue(Value* value, bool& result) {
   auto def = value->def;
   if (def && def->opcode == &OPCODE_ASSIGN_info) {
     // Value comes from an assignment - recursively find if it comes from
@@ -162,8 +178,10 @@ Value* SimplificationPass::CheckValue(Value* value) {
       }
       replacement = def->src1.value;
     }
+    result = true;
     return replacement;
   }
+  result = false;
   return value;
 }
 
diff --git a/src/xenia/cpu/compiler/passes/simplification_pass.h b/src/xenia/cpu/compiler/passes/simplification_pass.h
index 70275f8b4..2ba6efad7 100644
--- a/src/xenia/cpu/compiler/passes/simplification_pass.h
+++ b/src/xenia/cpu/compiler/passes/simplification_pass.h
@@ -10,27 +10,27 @@
 #ifndef XENIA_CPU_COMPILER_PASSES_SIMPLIFICATION_PASS_H_
 #define XENIA_CPU_COMPILER_PASSES_SIMPLIFICATION_PASS_H_
 
-#include "xenia/cpu/compiler/compiler_pass.h"
+#include "xenia/cpu/compiler/passes/conditional_group_subpass.h"
 
 namespace xe {
 namespace cpu {
 namespace compiler {
 namespace passes {
 
-class SimplificationPass : public CompilerPass {
+class SimplificationPass : public ConditionalGroupSubpass {
  public:
   SimplificationPass();
   ~SimplificationPass() override;
 
-  bool Run(hir::HIRBuilder* builder) override;
+  bool Run(hir::HIRBuilder* builder, bool& result) override;
 
  private:
-  void EliminateConversions(hir::HIRBuilder* builder);
-  void CheckTruncate(hir::Instr* i);
-  void CheckByteSwap(hir::Instr* i);
+  bool EliminateConversions(hir::HIRBuilder* builder);
+  bool CheckTruncate(hir::Instr* i);
+  bool CheckByteSwap(hir::Instr* i);
 
-  void SimplifyAssignments(hir::HIRBuilder* builder);
-  hir::Value* CheckValue(hir::Value* value);
+  bool SimplifyAssignments(hir::HIRBuilder* builder);
+  hir::Value* CheckValue(hir::Value* value, bool& result);
 };
 
 }  // namespace passes
diff --git a/src/xenia/cpu/ppc/ppc_translator.cc b/src/xenia/cpu/ppc/ppc_translator.cc
index ec1768163..d408f75b1 100644
--- a/src/xenia/cpu/ppc/ppc_translator.cc
+++ b/src/xenia/cpu/ppc/ppc_translator.cc
@@ -53,15 +53,16 @@ PPCTranslator::PPCTranslator(PPCFrontend* frontend) : frontend_(frontend) {
   if (validate) compiler_->AddPass(std::make_unique<passes::ValidationPass>());
   compiler_->AddPass(std::make_unique<passes::ContextPromotionPass>());
   if (validate) compiler_->AddPass(std::make_unique<passes::ValidationPass>());
-  // TODO(gibbed): loop until these passes stop making changes?
-  for (int i = 0; i < 5; ++i) {
-    compiler_->AddPass(std::make_unique<passes::SimplificationPass>());
-    if (validate)
-      compiler_->AddPass(std::make_unique<passes::ValidationPass>());
-    compiler_->AddPass(std::make_unique<passes::ConstantPropagationPass>());
-    if (validate)
-      compiler_->AddPass(std::make_unique<passes::ValidationPass>());
-  }
+
+  // Grouped simplification + constant propagation.
+  // Loops until no changes are made.
+  auto sap = std::make_unique<passes::ConditionalGroupPass>();
+  sap->AddPass(std::make_unique<passes::SimplificationPass>());
+  if (validate) sap->AddPass(std::make_unique<passes::ValidationPass>());
+  sap->AddPass(std::make_unique<passes::ConstantPropagationPass>());
+  if (validate) sap->AddPass(std::make_unique<passes::ValidationPass>());
+  compiler_->AddPass(std::move(sap));
+
   if (backend->machine_info()->supports_extended_load_store) {
     // Backend supports the advanced LOAD/STORE instructions.
     // These will save us a lot of HIR opcodes.