From 6392292ef37ca22d70fc002ff117370508dbb6be Mon Sep 17 00:00:00 2001
From: Jakob Botsch Nielsen <jakob.botsch.nielsen@gmail.com>
Date: Thu, 1 Aug 2024 21:33:07 +0200
Subject: [PATCH 1/3] JIT: Make sure static ctor flag check uses a volatile
load
Otherwise the hardware is allowed to reorder loads of its static fields
to happen before the initialization check.
---
src/coreclr/jit/helperexpansion.cpp | 2 ++
1 file changed, 2 insertions(+)
diff --git a/src/coreclr/jit/helperexpansion.cpp b/src/coreclr/jit/helperexpansion.cpp
index 1580a3fbba362e..089ba3978be65e 100644
--- a/src/coreclr/jit/helperexpansion.cpp
+++ b/src/coreclr/jit/helperexpansion.cpp
@@ -1418,6 +1418,7 @@ bool Compiler::fgExpandStaticInitForCall(BasicBlock** pBlock, Statement* stmt, G
// Don't fold ADD(CNS1, CNS2) here since the result won't be reloc-friendly for AOT
GenTree* offsetNode = gtNewOperNode(GT_ADD, TYP_I_IMPL, baseAddr, gtNewIconNode(isInitOffset));
isInitedActualValueNode = gtNewIndir(TYP_I_IMPL, offsetNode, GTF_IND_NONFAULTING);
+ isInitedActualValueNode->gtFlags |= GTF_IND_VOLATILE;
// 0 means "initialized" on NativeAOT
isInitedExpectedValue = gtNewIconNode(0, TYP_I_IMPL);
@@ -1427,6 +1428,7 @@ bool Compiler::fgExpandStaticInitForCall(BasicBlock** pBlock, Statement* stmt, G
assert(isInitOffset == 0);
isInitedActualValueNode = gtNewIndOfIconHandleNode(TYP_INT, (size_t)flagAddr.addr, GTF_ICON_GLOBAL_PTR, false);
+ isInitedActualValueNode->gtFlags |= GTF_IND_VOLATILE;
// Check ClassInitFlags::INITIALIZED_FLAG bit
isInitedActualValueNode = gtNewOperNode(GT_AND, TYP_INT, isInitedActualValueNode, gtNewIconNode(1));
From c81e50bda284a879ba025fe99dd2fafb0efb6713 Mon Sep 17 00:00:00 2001
From: Jakob Botsch Nielsen <jakob.botsch.nielsen@gmail.com>
Date: Thu, 1 Aug 2024 21:37:48 +0200
Subject: [PATCH 2/3] Nit
---
src/coreclr/jit/helperexpansion.cpp | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/src/coreclr/jit/helperexpansion.cpp b/src/coreclr/jit/helperexpansion.cpp
index 089ba3978be65e..6f8b8456db428e 100644
--- a/src/coreclr/jit/helperexpansion.cpp
+++ b/src/coreclr/jit/helperexpansion.cpp
@@ -1417,8 +1417,7 @@ bool Compiler::fgExpandStaticInitForCall(BasicBlock** pBlock, Statement* stmt, G
// Don't fold ADD(CNS1, CNS2) here since the result won't be reloc-friendly for AOT
GenTree* offsetNode = gtNewOperNode(GT_ADD, TYP_I_IMPL, baseAddr, gtNewIconNode(isInitOffset));
- isInitedActualValueNode = gtNewIndir(TYP_I_IMPL, offsetNode, GTF_IND_NONFAULTING);
- isInitedActualValueNode->gtFlags |= GTF_IND_VOLATILE;
+ isInitedActualValueNode = gtNewIndir(TYP_I_IMPL, offsetNode, GTF_IND_NONFAULTING | GTF_IND_VOLATILE);
// 0 means "initialized" on NativeAOT
isInitedExpectedValue = gtNewIconNode(0, TYP_I_IMPL);
From ee9f88b03b77920e5eed331fdef277231f93453c Mon Sep 17 00:00:00 2001
From: Jakob Botsch Nielsen <jakob.botsch.nielsen@gmail.com>
Date: Fri, 2 Aug 2024 17:07:02 +0200
Subject: [PATCH 3/3] Set GTF_ORDER_SIDEEFF
---
src/coreclr/jit/helperexpansion.cpp | 1 +
1 file changed, 1 insertion(+)
diff --git a/src/coreclr/jit/helperexpansion.cpp b/src/coreclr/jit/helperexpansion.cpp
index 6f8b8456db428e..3d5678d2743b42 100644
--- a/src/coreclr/jit/helperexpansion.cpp
+++ b/src/coreclr/jit/helperexpansion.cpp
@@ -1428,6 +1428,7 @@ bool Compiler::fgExpandStaticInitForCall(BasicBlock** pBlock, Statement* stmt, G
isInitedActualValueNode = gtNewIndOfIconHandleNode(TYP_INT, (size_t)flagAddr.addr, GTF_ICON_GLOBAL_PTR, false);
isInitedActualValueNode->gtFlags |= GTF_IND_VOLATILE;
+ isInitedActualValueNode->SetHasOrderingSideEffect();
// Check ClassInitFlags::INITIALIZED_FLAG bit
isInitedActualValueNode = gtNewOperNode(GT_AND, TYP_INT, isInitedActualValueNode, gtNewIconNode(1));