From 92e57309ee95e8489b7e9e773f484f57626d5f70 Mon Sep 17 00:00:00 2001
From: clabby <ben@clab.by>
Date: Wed, 7 Aug 2024 10:38:34 -0600
Subject: [PATCH] works!

---
 cannon/mipsevm/exec/mips_instructions.go      | 25 +++++++++++++------
 cannon/mipsevm/exec/mips_syscalls.go          |  1 +
 .../multithreaded/instrumented_test.go        |  2 +-
 cannon/mipsevm/multithreaded/mips.go          |  1 +
 cannon/mipsevm/program/patch.go               |  7 +++---
 cannon/testdata/example/Makefile              |  2 +-
 6 files changed, 24 insertions(+), 14 deletions(-)

diff --git a/cannon/mipsevm/exec/mips_instructions.go b/cannon/mipsevm/exec/mips_instructions.go
index 8e0e4c0934b5f..4da382ac89c03 100644
--- a/cannon/mipsevm/exec/mips_instructions.go
+++ b/cannon/mipsevm/exec/mips_instructions.go
@@ -51,7 +51,7 @@ func ExecMipsCoreStepLogic(cpu *mipsevm.CpuScalars, registers *[32]uint64, memor
 			// SignExtImm
 			rt = SignExtend(insn&0xFFFF, 16)
 		}
-	} else if opcode >= 0x28 || opcode == 0x22 || opcode == 0x26 || opcode == 0x1A || opcode == 0x1B {
+	} else if opcode >= 0x27 || opcode == 0x22 || opcode == 0x26 || opcode == 0x1A || opcode == 0x1B {
 		// store rt value with store
 		rt = registers[rtReg]
 
@@ -63,7 +63,7 @@ func ExecMipsCoreStepLogic(cpu *mipsevm.CpuScalars, registers *[32]uint64, memor
 		return HandleBranch(cpu, registers, opcode, insn, rtReg, rs)
 	}
 
-	storeAddr := uint64(0xFF_FF_FF_FF_FF_FF_FF_FF)
+	storeAddr := ^uint64(0)
 	// memory fetch (all I-type)
 	// we do the load for stores also
 	mem := uint64(0)
@@ -114,7 +114,7 @@ func ExecMipsCoreStepLogic(cpu *mipsevm.CpuScalars, registers *[32]uint64, memor
 	}
 
 	// write memory
-	if storeAddr != 0xFF_FF_FF_FF_FF_FF_FF_FF {
+	if storeAddr != ^uint64(0) {
 		memTracker.TrackMemAccess(storeAddr)
 		memory.SetDoubleWord(storeAddr, val)
 	}
@@ -281,7 +281,7 @@ func ExecuteMipsInstruction(insn, opcode, fun, rs, rt, mem uint64) uint64 {
 		case 0x22: // lwl
 			val := mem << ((rs & 3) * 8)
 			mask := uint64(uint32(0xFFFFFFFF) << ((rs & 3) * 8))
-			return SignExtend((rt & ^mask)|val, 32)
+			return SignExtend(((rt & ^mask)|val)&0xFFFFFFFF, 32)
 		case 0x23: // lw
 			return SignExtend((mem>>(32-((rs&0x4)<<3)))&0xFFFFFFFF, 32)
 		case 0x24: // lbu
@@ -291,7 +291,7 @@ func ExecuteMipsInstruction(insn, opcode, fun, rs, rt, mem uint64) uint64 {
 		case 0x26: //  lwr
 			val := mem >> (24 - (rs&3)*8)
 			mask := uint64(uint32(0xFFFFFFFF) >> (24 - (rs&3)*8))
-			return SignExtend((rt & ^mask)|val, 32)
+			return SignExtend(((rt & ^mask)|val)&0xFFFFFFFF, 32)
 		case 0x28: //  sb
 			val := (rt & 0xFF) << (56 - (rs&7)*8)
 			mask := 0xFFFFFFFFFFFFFFFF ^ uint64(0xFF<<(56-(rs&7)*8))
@@ -319,7 +319,10 @@ func ExecuteMipsInstruction(insn, opcode, fun, rs, rt, mem uint64) uint64 {
 		case 0x30: //  ll
 			return SignExtend((mem>>(32-((rs&0x4)<<3)))&0xFFFFFFFF, 32)
 		case 0x38: //  sc
-			return rt
+			sl := 32 - ((rs & 0x4) << 3)
+			val := (rt & 0xFFFFFFFF) << sl
+			mask := 0xFFFFFFFFFFFFFFFF ^ uint64(0xFFFFFFFF<<sl)
+			return (mem & mask) | val
 		// MIPS64
 		case 0x1A: // ldl
 			sl := (rs & 0x7) << 3
@@ -348,9 +351,15 @@ func ExecuteMipsInstruction(insn, opcode, fun, rs, rt, mem uint64) uint64 {
 		case 0x37: // ld
 			return mem
 		case 0x3C: // scd
-			return rt
+			sl := (rs & 0x7) << 3
+			val := rt << sl
+			mask := uint64(0xFFFFFFFFFFFFFFFF) << sl
+			return (mem & ^mask) | val
 		case 0x3F: // sd
-			return rt
+			sl := (rs & 0x7) << 3
+			val := rt << sl
+			mask := uint64(0xFFFFFFFFFFFFFFFF) << sl
+			return (mem & ^mask) | val
 		default:
 			panic(fmt.Sprintf("invalid instruction: %x", insn))
 		}
diff --git a/cannon/mipsevm/exec/mips_syscalls.go b/cannon/mipsevm/exec/mips_syscalls.go
index 7973f4fc120d5..9cc38237fc7c3 100644
--- a/cannon/mipsevm/exec/mips_syscalls.go
+++ b/cannon/mipsevm/exec/mips_syscalls.go
@@ -37,6 +37,7 @@ const (
 	SysSigaltstack   = 5129
 	SysRtSigaction   = 5013
 	SysPrlimit64     = 5297
+	SysGetRLimit     = 5095
 	SysClose         = 5003
 	SysPread64       = 5016
 	SysFstat64       = 5005
diff --git a/cannon/mipsevm/multithreaded/instrumented_test.go b/cannon/mipsevm/multithreaded/instrumented_test.go
index c20126d3ca22a..18d81adafef76 100644
--- a/cannon/mipsevm/multithreaded/instrumented_test.go
+++ b/cannon/mipsevm/multithreaded/instrumented_test.go
@@ -37,7 +37,7 @@ func TestInstrumentedState_MultithreadedProgram(t *testing.T) {
 
 	var stdOutBuf, stdErrBuf bytes.Buffer
 	us := NewInstrumentedState(state, oracle, io.MultiWriter(&stdOutBuf, os.Stdout), io.MultiWriter(&stdErrBuf, os.Stderr), testutil.CreateLogger())
-	for i := 0; i < 1_000_000; i++ {
+	for i := 0; i < 2_000_000; i++ {
 		if us.GetState().GetExited() {
 			break
 		}
diff --git a/cannon/mipsevm/multithreaded/mips.go b/cannon/mipsevm/multithreaded/mips.go
index bc8aa53a4358f..03f504151ebd4 100644
--- a/cannon/mipsevm/multithreaded/mips.go
+++ b/cannon/mipsevm/multithreaded/mips.go
@@ -149,6 +149,7 @@ func (m *InstrumentedState) handleSyscall() error {
 	case exec.SysSigaltstack:
 	case exec.SysRtSigaction:
 	case exec.SysPrlimit64:
+	case exec.SysGetRLimit:
 	case exec.SysClose:
 	case exec.SysPread64:
 	case exec.SysFstat64:
diff --git a/cannon/mipsevm/program/patch.go b/cannon/mipsevm/program/patch.go
index f1efe6f87c100..a1f96ac83e956 100644
--- a/cannon/mipsevm/program/patch.go
+++ b/cannon/mipsevm/program/patch.go
@@ -3,7 +3,6 @@ package program
 import (
 	"bytes"
 	"debug/elf"
-	"encoding/binary"
 	"fmt"
 
 	"github.com/ethereum-optimism/optimism/cannon/mipsevm"
@@ -47,6 +46,8 @@ func PatchGo(f *elf.File, st mipsevm.FPVMState) error {
 			})); err != nil {
 				return fmt.Errorf("failed to patch Go runtime.gcenable: %w", err)
 			}
+		case "runtime.MemProfileRate":
+			st.GetMemory().SetDoubleWord(uint64(s.Value), 0)
 		}
 	}
 	return nil
@@ -63,9 +64,7 @@ func PatchStack(st mipsevm.FPVMState) error {
 	st.GetRegisters()[29] = sp
 
 	storeMem := func(addr uint64, v uint64) {
-		var dat [8]byte
-		binary.BigEndian.PutUint64(dat[:], v)
-		_ = st.GetMemory().SetMemoryRange(addr, bytes.NewReader(dat[:]))
+		st.GetMemory().SetDoubleWord(addr, v)
 	}
 
 	// init argc, argv, aux on stack
diff --git a/cannon/testdata/example/Makefile b/cannon/testdata/example/Makefile
index 48bccd9fce92f..e7c7bc8e0e57c 100644
--- a/cannon/testdata/example/Makefile
+++ b/cannon/testdata/example/Makefile
@@ -13,7 +13,7 @@ bin:
 # verify output with: readelf -h bin/<name>.elf
 # result is mips64, big endian, R3000
 bin/%.elf: bin
-	cd $(@:bin/%.elf=%) && GOOS=linux GODEBUG=memprofilerate=0 GOARCH=mips64 GOMIPS64=softfloat go build -o ../$@ .
+	cd $(@:bin/%.elf=%) && GOOS=linux GOARCH=mips64 GOMIPS64=softfloat go build -o ../$@ .
 
 # take any ELF and dump it
 # TODO: currently have the little-endian toolchain, but should use the big-endian one. The -EB compat flag works though.