Skip stp/ldp only for unwind portion of prolog/epilog (#85657)

* Skip stp/ldp only for unwind portion of prolog/epilog * Rename unwindarm.cpp -> unwindarmarch.cpp * review feedback
dotnet · May 3, 2023 · 372b01f · 372b01f
1 parent 56eff9f
commit 372b01f
Show file tree

Hide file tree

Showing 9 changed files with 44 additions and 18 deletions.
diff --git a/src/coreclr/jit/CMakeLists.txt b/src/coreclr/jit/CMakeLists.txt
@@ -210,7 +210,7 @@ set( JIT_ARM_SOURCES
   lsraarmarch.cpp
   lsraarm.cpp
   targetarm.cpp
-  unwindarm.cpp
+  unwindarmarch.cpp
 )
 
 set( JIT_I386_SOURCES
@@ -238,7 +238,7 @@ set( JIT_ARM64_SOURCES
   simd.cpp
   simdashwintrinsic.cpp
   targetarm64.cpp
-  unwindarm.cpp
+  unwindarmarch.cpp
   unwindarm64.cpp
   hwintrinsicarm64.cpp
   hwintrinsiccodegenarm64.cpp

diff --git a/src/coreclr/jit/codegencommon.cpp b/src/coreclr/jit/codegencommon.cpp
@@ -5970,6 +5970,7 @@ void CodeGen::genFnProlog()
         genEstablishFramePointer(compiler->codeGen->genSPtoFPdelta(), reportUnwindData);
     }
 #endif // TARGET_AMD64
+    compiler->unwindEndProlog();
 
 //-------------------------------------------------------------------------
 //
@@ -6297,7 +6298,6 @@ void CodeGen::genFnProlog()
 #endif // defined(DEBUG) && defined(TARGET_XARCH)
 
     GetEmitter()->emitEndProlog();
-    compiler->unwindEndProlog();
 }
 #ifdef _PREFAST_
 #pragma warning(pop)

diff --git a/src/coreclr/jit/compiler.cpp b/src/coreclr/jit/compiler.cpp
@@ -1928,8 +1928,10 @@ void Compiler::compInit(ArenaAllocator*       pAlloc,
     compNeedsGSSecurityCookie = false;
     compGSReorderStackLayout  = false;
 
-    compGeneratingProlog = false;
-    compGeneratingEpilog = false;
+    compGeneratingProlog       = false;
+    compGeneratingEpilog       = false;
+    compGeneratingUnwindProlog = false;
+    compGeneratingUnwindEpilog = false;
 
     compPostImportationCleanupDone = false;
     compLSRADone                   = false;

diff --git a/src/coreclr/jit/compiler.h b/src/coreclr/jit/compiler.h
@@ -9289,6 +9289,8 @@ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
 
     bool compGeneratingProlog;
     bool compGeneratingEpilog;
+    bool compGeneratingUnwindProlog;
+    bool compGeneratingUnwindEpilog;
     bool compNeedsGSSecurityCookie; // There is an unsafe buffer (or localloc) on the stack.
                                     // Insert cookie on frame and code to check the cookie, like VC++ -GS.
     bool compGSReorderStackLayout;  // There is an unsafe buffer on the stack, reorder locals and make local

diff --git a/src/coreclr/jit/emitarm64.cpp b/src/coreclr/jit/emitarm64.cpp
@@ -16645,18 +16645,12 @@ emitter::RegisterOrder emitter::IsOptimizableLdrStrWithPair(
         return eRO_none;
     }
 
-    // Don't remove instructions whilst in prologs or epilogs, as these contain  "unwindable"
-    // parts, where we need to report unwind codes to the OS,
-    if (emitIGisInProlog(emitCurIG) || emitIGisInEpilog(emitCurIG))
+    if (emitComp->compGeneratingUnwindProlog || emitComp->compGeneratingUnwindEpilog)
     {
+        // Don't remove instructions while generating "unwind" part of prologs or epilogs,
+        // because for those instructions, we need to report unwind codes to the OS.
         return eRO_none;
     }
-#ifdef FEATURE_EH_FUNCLETS
-    if (emitIGisInFuncletProlog(emitCurIG) || emitIGisInFuncletEpilog(emitCurIG))
-    {
-        return eRO_none;
-    }
-#endif
 
     return optimisationOrder;
 }

diff --git a/src/coreclr/jit/unwindamd64.cpp b/src/coreclr/jit/unwindamd64.cpp
@@ -86,6 +86,8 @@ short Compiler::mapRegNumToDwarfReg(regNumber reg)
 //
 void Compiler::unwindBegProlog()
 {
+    assert(!compGeneratingUnwindProlog);
+    compGeneratingUnwindProlog = true;
 #ifdef UNIX_AMD64_ABI
     if (generateCFIUnwindCodes())
     {
@@ -129,6 +131,8 @@ void Compiler::unwindBegPrologWindows()
 void Compiler::unwindEndProlog()
 {
     assert(compGeneratingProlog);
+    assert(compGeneratingUnwindProlog);
+    compGeneratingUnwindProlog = false;
 }
 
 //------------------------------------------------------------------------
@@ -138,6 +142,8 @@ void Compiler::unwindEndProlog()
 void Compiler::unwindBegEpilog()
 {
     assert(compGeneratingEpilog);
+    assert(!compGeneratingUnwindEpilog);
+    compGeneratingUnwindEpilog = true;
 }
 
 //------------------------------------------------------------------------
@@ -147,6 +153,8 @@ void Compiler::unwindBegEpilog()
 void Compiler::unwindEndEpilog()
 {
     assert(compGeneratingEpilog);
+    assert(compGeneratingUnwindEpilog);
+    compGeneratingUnwindEpilog = false;
 }
 
 //------------------------------------------------------------------------

diff --git a/src/coreclr/jit/unwindarm.cpp → src/coreclr/jit/unwindarmarch.cpp b/src/coreclr/jit/unwindarm.cpp → src/coreclr/jit/unwindarmarch.cpp
@@ -126,8 +126,6 @@ short Compiler::mapRegNumToDwarfReg(regNumber reg)
 }
 #endif // TARGET_ARM && FEATURE_CFI_SUPPORT
 
-#ifdef TARGET_ARMARCH
-
 /*XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
 XX                                                                           XX
@@ -140,6 +138,8 @@ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
 void Compiler::unwindBegProlog()
 {
     assert(compGeneratingProlog);
+    assert(!compGeneratingUnwindProlog);
+    compGeneratingUnwindProlog = true;
 
 #if defined(FEATURE_CFI_SUPPORT)
     if (generateCFIUnwindCodes())
@@ -167,11 +167,15 @@ void Compiler::unwindBegProlog()
 void Compiler::unwindEndProlog()
 {
     assert(compGeneratingProlog);
+    assert(compGeneratingUnwindProlog);
+    compGeneratingUnwindProlog = false;
 }
 
 void Compiler::unwindBegEpilog()
 {
     assert(compGeneratingEpilog);
+    assert(!compGeneratingUnwindEpilog);
+    compGeneratingUnwindEpilog = true;
 
 #if defined(FEATURE_CFI_SUPPORT)
     if (generateCFIUnwindCodes())
@@ -186,6 +190,8 @@ void Compiler::unwindBegEpilog()
 void Compiler::unwindEndEpilog()
 {
     assert(compGeneratingEpilog);
+    assert(compGeneratingUnwindEpilog);
+    compGeneratingUnwindEpilog = false;
 }
 
 #if defined(TARGET_ARM)
@@ -2579,5 +2585,3 @@ void DumpUnwindInfo(Compiler*         comp,
 #endif // DEBUG
 
 #endif // defined(TARGET_ARM)
-
-#endif // TARGET_ARMARCH
diff --git a/src/coreclr/jit/unwindloongarch64.cpp b/src/coreclr/jit/unwindloongarch64.cpp
@@ -891,6 +891,8 @@ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
 void Compiler::unwindBegProlog()
 {
     assert(compGeneratingProlog);
+    assert(!compGeneratingUnwindProlog);
+    compGeneratingUnwindProlog = true;
 
 #if defined(FEATURE_CFI_SUPPORT)
     if (generateCFIUnwindCodes())
@@ -918,11 +920,15 @@ void Compiler::unwindBegProlog()
 void Compiler::unwindEndProlog()
 {
     assert(compGeneratingProlog);
+    assert(compGeneratingUnwindProlog);
+    compGeneratingUnwindProlog = false;
 }
 
 void Compiler::unwindBegEpilog()
 {
     assert(compGeneratingEpilog);
+    assert(!compGeneratingUnwindEpilog);
+    compGeneratingUnwindEpilog = true;
 
 #if defined(FEATURE_CFI_SUPPORT)
     if (generateCFIUnwindCodes())
@@ -937,6 +943,8 @@ void Compiler::unwindBegEpilog()
 void Compiler::unwindEndEpilog()
 {
     assert(compGeneratingEpilog);
+    assert(compGeneratingUnwindEpilog);
+    compGeneratingUnwindEpilog = false;
 }
 
 // The instructions between the last captured "current state" and the current instruction

diff --git a/src/coreclr/jit/unwindriscv64.cpp b/src/coreclr/jit/unwindriscv64.cpp
@@ -669,6 +669,8 @@ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
 void Compiler::unwindBegProlog()
 {
     assert(compGeneratingProlog);
+    assert(!compGeneratingUnwindProlog);
+    compGeneratingUnwindProlog = true;
 
 #if defined(FEATURE_CFI_SUPPORT)
     if (generateCFIUnwindCodes())
@@ -696,11 +698,15 @@ void Compiler::unwindBegProlog()
 void Compiler::unwindEndProlog()
 {
     assert(compGeneratingProlog);
+    assert(compGeneratingUnwindProlog);
+    compGeneratingUnwindProlog = false;
 }
 
 void Compiler::unwindBegEpilog()
 {
     assert(compGeneratingEpilog);
+    assert(!compGeneratingUnwindEpilog);
+    compGeneratingUnwindEpilog = true;
 
 #if defined(FEATURE_CFI_SUPPORT)
     if (generateCFIUnwindCodes())
@@ -715,6 +721,8 @@ void Compiler::unwindBegEpilog()
 void Compiler::unwindEndEpilog()
 {
     assert(compGeneratingEpilog);
+    assert(compGeneratingUnwindEpilog);
+    compGeneratingUnwindEpilog = false;
 }
 
 // The instructions between the last captured "current state" and the current instruction