From 48009fd898c2732652480bdf2c086ab6f77b2a7d Mon Sep 17 00:00:00 2001
From: JosJuice <josjuice@gmail.com>
Date: Fri, 5 Dec 2025 19:27:06 +0100
Subject: [PATCH] Jit64: Return current value from RCOpArg::IsImm

The constant propagation PR made it so that a guest register can be
present in the register cache as both a host register and an immediate
at the same time. If such a guest register is requested from the
register cache, the register cache prefers returning it as a host
register. However, RCOpArg::IsImm still returns true in this case. This
is confusing, especially since OpArg::IsImm does not return true if the
RCOpArg is converted into an OpArg.

This commit makes RCOpArg::IsImm check whether RCOpArg::Location returns
an immediate, so that RCOpArg::IsImm returns false when a host register
is being used. Code that wants to know whether an immediate exists in
the register cache rather than whether an immediate is currently being
used should call RegCache::IsImm instead.
---
 .../PowerPC/Jit64/RegCache/JitRegCache.cpp    | 41 -------------------
 .../Core/PowerPC/Jit64/RegCache/JitRegCache.h |  6 +--
 2 files changed, 3 insertions(+), 44 deletions(-)

diff --git a/Source/Core/Core/PowerPC/Jit64/RegCache/JitRegCache.cpp b/Source/Core/Core/PowerPC/Jit64/RegCache/JitRegCache.cpp
index 2a787f31207..b39ed2e5616 100644
--- a/Source/Core/Core/PowerPC/Jit64/RegCache/JitRegCache.cpp
+++ b/Source/Core/Core/PowerPC/Jit64/RegCache/JitRegCache.cpp
@@ -132,47 +132,6 @@ void RCOpArg::Unlock()
   contents = std::monostate{};
 }
 
-bool RCOpArg::IsImm() const
-{
-  if (const preg_t* preg = std::get_if<preg_t>(&contents))
-  {
-    return rc->IsImm(*preg);
-  }
-  else if (std::holds_alternative<u32>(contents))
-  {
-    return true;
-  }
-  return false;
-}
-
-s32 RCOpArg::SImm32() const
-{
-  if (const preg_t* preg = std::get_if<preg_t>(&contents))
-  {
-    return rc->SImm32(*preg);
-  }
-  else if (const u32* imm = std::get_if<u32>(&contents))
-  {
-    return static_cast<s32>(*imm);
-  }
-  ASSERT(false);
-  return 0;
-}
-
-u32 RCOpArg::Imm32() const
-{
-  if (const preg_t* preg = std::get_if<preg_t>(&contents))
-  {
-    return rc->Imm32(*preg);
-  }
-  else if (const u32* imm = std::get_if<u32>(&contents))
-  {
-    return *imm;
-  }
-  ASSERT(false);
-  return 0;
-}
-
 RCX64Reg::RCX64Reg() = default;
 
 RCX64Reg::RCX64Reg(RegCache* rc_, preg_t preg) : rc(rc_), contents(preg)
diff --git a/Source/Core/Core/PowerPC/Jit64/RegCache/JitRegCache.h b/Source/Core/Core/PowerPC/Jit64/RegCache/JitRegCache.h
index 0a7ab3836d2..4d74285a513 100644
--- a/Source/Core/Core/PowerPC/Jit64/RegCache/JitRegCache.h
+++ b/Source/Core/Core/PowerPC/Jit64/RegCache/JitRegCache.h
@@ -49,9 +49,9 @@ public:
 
   void Unlock();
 
-  bool IsImm() const;
-  s32 SImm32() const;
-  u32 Imm32() const;
+  bool IsImm() const { return Location().IsImm(); }
+  s32 SImm32() const { return Location().SImm32(); }
+  u32 Imm32() const { return Location().Imm32(); }
   bool IsZero() const { return IsImm() && Imm32() == 0; }
 
 private: