[X86][APX] Disable PP2/PPX generation on Windows#178122
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phoebewang merged 4 commits intollvm:mainfrom Feb 2, 2026
Merged
[X86][APX] Disable PP2/PPX generation on Windows#178122phoebewang merged 4 commits intollvm:mainfrom
phoebewang merged 4 commits intollvm:mainfrom
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The PUSH2/POP2/PPX instructions for APX require updates to the Microsoft Windows OS x64 calling convention documented at https://learn.microsoft.com/en-us/cpp/build/exception-handling-x64?view=msvc-170 due to lack of suitable unwinder opcodes that can support APX PUSH2/POP2/PPX. The PR request disables this support by default for code robustness; workloads that choose to explicitly enable this support can change the default behavior by explicitly specifying the flag options that enable this support e.g. for experimentation or code paths that do not need unwinder support.
phoebewang
requested review from
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fzou1
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backend:X86
clang:driver
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@llvm/pr-subscribers-clang-driver Author: Phoebe Wang (phoebewang) ChangesThe PUSH2/POP2/PPX instructions for APX require updates to the Microsoft Windows OS x64 calling convention documented at https://learn.microsoft.com/en-us/cpp/build/exception-handling-x64?view=msvc-170 due to lack of suitable unwinder opcodes that can support APX PUSH2/POP2/PPX. The PR request disables this support by default for code robustness; workloads that choose to explicitly enable this support can change the default behavior by explicitly specifying the flag options that enable this support e.g. for experimentation or code paths that do not need unwinder support. 8 Files Affected:
diff --git a/clang/include/clang/Options/Options.td b/clang/include/clang/Options/Options.td
index 43727236ed5a4..1f67441fb389b 100644
--- a/clang/include/clang/Options/Options.td
+++ b/clang/include/clang/Options/Options.td
@@ -7043,12 +7043,8 @@ def mapx_features_EQ : CommaJoined<["-"], "mapx-features=">, Group<m_x86_Feature
HelpText<"Enable features of APX">, Values<"egpr,push2pop2,ppx,ndd,ccmp,nf,cf,zu">, Visibility<[ClangOption, CLOption, FlangOption]>;
def mno_apx_features_EQ : CommaJoined<["-"], "mno-apx-features=">, Group<m_x86_Features_Group>,
HelpText<"Disable features of APX">, Values<"egpr,push2pop2,ppx,ndd,ccmp,nf,cf,zu">, Visibility<[ClangOption, CLOption, FlangOption]>;
-def mapxf : Flag<["-"], "mapxf">, Alias<mapx_features_EQ>,
- AliasArgs<["egpr","push2pop2","ppx","ndd","ccmp","nf","zu"]>,
- Group<m_x86_Features_Group>;
-def mno_apxf : Flag<["-"], "mno-apxf">, Alias<mno_apx_features_EQ>,
- AliasArgs<["egpr","push2pop2","ppx","ndd","ccmp","nf","zu"]>,
- Group<m_x86_Features_Group>;
+def mapxf : Flag<["-"], "mapxf">, Group<m_x86_Features_Group>;
+def mno_apxf : Flag<["-"], "mno-apxf">, Group<m_x86_Features_Group>;
def mapx_inline_asm_use_gpr32 : Flag<["-"], "mapx-inline-asm-use-gpr32">, Group<m_Group>,
HelpText<"Enable use of GPR32 in inline assembly for APX">;
} // let Flags = [TargetSpecific]
diff --git a/clang/lib/Basic/Targets/X86.cpp b/clang/lib/Basic/Targets/X86.cpp
index f00d435937b92..f0a1874be8111 100644
--- a/clang/lib/Basic/Targets/X86.cpp
+++ b/clang/lib/Basic/Targets/X86.cpp
@@ -164,6 +164,11 @@ bool X86TargetInfo::initFeatureMap(
for (auto &F : CPUFeatures)
setFeatureEnabled(Features, F, true);
+ if (Features.lookup("egpr") && getTriple().isOSWindows()) {
+ setFeatureEnabled(Features, "push2pop2", false);
+ setFeatureEnabled(Features, "ppx", false);
+ }
+
std::vector<std::string> UpdatedFeaturesVec;
for (const auto &Feature : FeaturesVec) {
// Expand general-regs-only to -x86, -mmx and -sse
@@ -967,7 +972,7 @@ void X86TargetInfo::getTargetDefines(const LangOptions &Opts,
Builder.defineMacro("__CF__");
if (HasZU)
Builder.defineMacro("__ZU__");
- if (HasEGPR && HasPush2Pop2 && HasPPX && HasNDD && HasCCMP && HasNF && HasZU)
+ if (HasEGPR && HasNDD && HasCCMP && HasNF && HasZU)
Builder.defineMacro("__APX_F__");
if (HasEGPR && HasInlineAsmUseGPR32)
Builder.defineMacro("__APX_INLINE_ASM_USE_GPR32__");
diff --git a/clang/lib/Driver/ToolChains/Arch/X86.cpp b/clang/lib/Driver/ToolChains/Arch/X86.cpp
index d6e6657c521f0..7a0dea030615d 100644
--- a/clang/lib/Driver/ToolChains/Arch/X86.cpp
+++ b/clang/lib/Driver/ToolChains/Arch/X86.cpp
@@ -252,14 +252,33 @@ void x86::getX86TargetFeatures(const Driver &D, const llvm::Triple &Triple,
D.Diag(diag::err_drv_unsupported_opt_for_target)
<< A->getSpelling() << Triple.getTriple();
- if (A->getOption().matches(options::OPT_mapx_features_EQ) ||
+ if (IsNegative)
+ Name = Name.substr(3);
+ if (A->getOption().matches(options::OPT_mapxf) ||
+ A->getOption().matches(options::OPT_mno_apxf) ||
+ A->getOption().matches(options::OPT_mapx_features_EQ) ||
A->getOption().matches(options::OPT_mno_apx_features_EQ)) {
if (Not64Bit && !IsNegative)
D.Diag(diag::err_drv_unsupported_opt_for_target)
- << StringRef(A->getSpelling().str() + "|-mapxf")
+ << StringRef("-mapx-features=|-mapxf")
<< Triple.getTriple();
+ if (Name == "apxf") {
+ if (IsNegative) {
+ Features.insert(Features.end(),
+ {"-egpr", "-ndd", "-ccmp", "-nf", "-zu"});
+ if (!Triple.isOSWindows())
+ Features.insert(Features.end(), {"-push2pop2", "-ppx"});
+ } else {
+ Features.insert(Features.end(),
+ {"+egpr", "+ndd", "+ccmp", "+nf", "+zu"});
+ if (!Triple.isOSWindows())
+ Features.insert(Features.end(), {"+push2pop2", "+ppx"});
+ }
+ continue;
+ }
+
for (StringRef Value : A->getValues()) {
if (Value != "egpr" && Value != "push2pop2" && Value != "ppx" &&
Value != "ndd" && Value != "ccmp" && Value != "nf" &&
@@ -272,8 +291,6 @@ void x86::getX86TargetFeatures(const Driver &D, const llvm::Triple &Triple,
}
continue;
}
- if (IsNegative)
- Name = Name.substr(3);
Features.push_back(Args.MakeArgString((IsNegative ? "-" : "+") + Name));
}
diff --git a/clang/test/Driver/cl-x86-flags.c b/clang/test/Driver/cl-x86-flags.c
index 84270aae35f7a..f85828b370d9e 100644
--- a/clang/test/Driver/cl-x86-flags.c
+++ b/clang/test/Driver/cl-x86-flags.c
@@ -222,6 +222,6 @@ void f(void) {
// RUN: %clang_cl --target=x86_64-pc-windows -mapxf -### -- 2>&1 %s | FileCheck -check-prefix=APXF %s
// RUN: %clang_cl --target=x86_64-pc-windows -mapxf -mno-apxf -### -- 2>&1 %s | FileCheck -check-prefix=NO-APXF %s
// RUN: %clang_cl --target=x86_64-pc-windows -mapx-features=egpr,push2pop2,ppx,ndd,ccmp,nf,cf,zu -### -- 2>&1 %s | FileCheck -check-prefix=APXALL %s
-// APXF: "-target-feature" "+egpr" "-target-feature" "+push2pop2" "-target-feature" "+ppx" "-target-feature" "+ndd" "-target-feature" "+ccmp" "-target-feature" "+nf" "-target-feature" "+zu"
-// NO-APXF: "-target-feature" "-egpr" "-target-feature" "-push2pop2" "-target-feature" "-ppx" "-target-feature" "-ndd" "-target-feature" "-ccmp" "-target-feature" "-nf" "-target-feature" "-zu"
+// APXF: "-target-feature" "+egpr" "-target-feature" "+ndd" "-target-feature" "+ccmp" "-target-feature" "+nf" "-target-feature" "+zu"
+// NO-APXF: "-target-feature" "-egpr" "-target-feature" "-ndd" "-target-feature" "-ccmp" "-target-feature" "-nf" "-target-feature" "-zu"
// APXALL: "-target-feature" "+egpr" "-target-feature" "+push2pop2" "-target-feature" "+ppx" "-target-feature" "+ndd" "-target-feature" "+ccmp" "-target-feature" "+nf" "-target-feature" "+cf" "-target-feature" "+zu"
diff --git a/clang/test/Driver/x86-target-features.c b/clang/test/Driver/x86-target-features.c
index f1660b1afb518..c0f2340d0f9fe 100644
--- a/clang/test/Driver/x86-target-features.c
+++ b/clang/test/Driver/x86-target-features.c
@@ -443,8 +443,8 @@
// RUN: %clang --target=x86_64-unknown-linux-gnu -mno-apxf -mapxf %s -### -o %t.o 2>&1 | FileCheck -check-prefix=APXF %s
// RUN: %clang --target=x86_64-unknown-linux-gnu -mapxf -mno-apxf %s -### -o %t.o 2>&1 | FileCheck -check-prefix=NO-APXF %s
//
-// APXF: "-target-feature" "+egpr" "-target-feature" "+push2pop2" "-target-feature" "+ppx" "-target-feature" "+ndd" "-target-feature" "+ccmp" "-target-feature" "+nf" "-target-feature" "+zu"
-// NO-APXF: "-target-feature" "-egpr" "-target-feature" "-push2pop2" "-target-feature" "-ppx" "-target-feature" "-ndd" "-target-feature" "-ccmp" "-target-feature" "-nf" "-target-feature" "-zu"
+// APXF: "-target-feature" "+egpr" "-target-feature" "+ndd" "-target-feature" "+ccmp" "-target-feature" "+nf" "-target-feature" "+zu" "-target-feature" "+push2pop2" "-target-feature" "+ppx"
+// NO-APXF: "-target-feature" "-egpr" "-target-feature" "-ndd" "-target-feature" "-ccmp" "-target-feature" "-nf" "-target-feature" "-zu" "-target-feature" "-push2pop2" "-target-feature" "-ppx"
// RUN: %clang --target=x86_64-unknown-linux-gnu -mapx-features=egpr %s -### -o %t.o 2>&1 | FileCheck -check-prefix=EGPR %s
// RUN: %clang --target=x86_64-unknown-linux-gnu -mapx-features=push2pop2 %s -### -o %t.o 2>&1 | FileCheck -check-prefix=PUSH2POP2 %s
diff --git a/llvm/lib/Target/X86/X86Subtarget.cpp b/llvm/lib/Target/X86/X86Subtarget.cpp
index 61f288ffb909b..4e2e98410f325 100644
--- a/llvm/lib/Target/X86/X86Subtarget.cpp
+++ b/llvm/lib/Target/X86/X86Subtarget.cpp
@@ -257,6 +257,9 @@ void X86Subtarget::initSubtargetFeatures(StringRef CPU, StringRef TuneCPU,
std::string FullFS = X86_MC::ParseX86Triple(TargetTriple);
assert(!FullFS.empty() && "Failed to parse X86 triple");
+ if (TargetTriple.isOSWindows())
+ FullFS += ",-push2pop2,-ppx";
+
if (!FS.empty())
FullFS = (Twine(FullFS) + "," + FS).str();
diff --git a/llvm/lib/TargetParser/Host.cpp b/llvm/lib/TargetParser/Host.cpp
index 5d4fa2c88153c..7b1af1779a24a 100644
--- a/llvm/lib/TargetParser/Host.cpp
+++ b/llvm/lib/TargetParser/Host.cpp
@@ -2167,8 +2167,10 @@ StringMap<bool> sys::getHostCPUFeatures() {
bool HasAVX10 = HasLeaf7Subleaf1 && ((EDX >> 19) & 1);
bool HasAPXF = HasLeaf7Subleaf1 && ((EDX >> 21) & 1) && HasAPXSave;
Features["egpr"] = HasAPXF;
+#ifndef _WIN32
Features["push2pop2"] = HasAPXF;
Features["ppx"] = HasAPXF;
+#endif
Features["ndd"] = HasAPXF;
Features["ccmp"] = HasAPXF;
Features["nf"] = HasAPXF;
diff --git a/llvm/test/CodeGen/X86/apx/push2-pop2-cfi-seh.ll b/llvm/test/CodeGen/X86/apx/push2-pop2-cfi-seh.ll
index d6d4db3509103..071b297b49dc1 100644
--- a/llvm/test/CodeGen/X86/apx/push2-pop2-cfi-seh.ll
+++ b/llvm/test/CodeGen/X86/apx/push2-pop2-cfi-seh.ll
@@ -2,7 +2,9 @@
; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu | FileCheck %s --check-prefix=LIN-REF
; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -mattr=+push2pop2 | FileCheck %s --check-prefix=LIN
; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -mattr=+push2pop2,+ppx | FileCheck %s --check-prefix=LIN-PPX
+; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -mcpu=diamondrapids | FileCheck %s --check-prefix=LIN-PPX
; RUN: llc < %s -mtriple=x86_64-windows-msvc | FileCheck %s --check-prefix=WIN-REF
+; RUN: llc < %s -mtriple=x86_64-windows-msvc -mcpu=diamondrapids | FileCheck %s --check-prefix=WIN-REF
; RUN: llc < %s -mtriple=x86_64-windows-msvc -mattr=+push2pop2 | FileCheck %s --check-prefix=WIN
; RUN: llc < %s -mtriple=x86_64-windows-msvc -mattr=+push2pop2,+ppx | FileCheck %s --check-prefix=WIN-PPX
|
Member
|
@llvm/pr-subscribers-backend-x86 Author: Phoebe Wang (phoebewang) ChangesThe PUSH2/POP2/PPX instructions for APX require updates to the Microsoft Windows OS x64 calling convention documented at https://learn.microsoft.com/en-us/cpp/build/exception-handling-x64?view=msvc-170 due to lack of suitable unwinder opcodes that can support APX PUSH2/POP2/PPX. The PR request disables this support by default for code robustness; workloads that choose to explicitly enable this support can change the default behavior by explicitly specifying the flag options that enable this support e.g. for experimentation or code paths that do not need unwinder support. 8 Files Affected:
diff --git a/clang/include/clang/Options/Options.td b/clang/include/clang/Options/Options.td
index 43727236ed5a4..1f67441fb389b 100644
--- a/clang/include/clang/Options/Options.td
+++ b/clang/include/clang/Options/Options.td
@@ -7043,12 +7043,8 @@ def mapx_features_EQ : CommaJoined<["-"], "mapx-features=">, Group<m_x86_Feature
HelpText<"Enable features of APX">, Values<"egpr,push2pop2,ppx,ndd,ccmp,nf,cf,zu">, Visibility<[ClangOption, CLOption, FlangOption]>;
def mno_apx_features_EQ : CommaJoined<["-"], "mno-apx-features=">, Group<m_x86_Features_Group>,
HelpText<"Disable features of APX">, Values<"egpr,push2pop2,ppx,ndd,ccmp,nf,cf,zu">, Visibility<[ClangOption, CLOption, FlangOption]>;
-def mapxf : Flag<["-"], "mapxf">, Alias<mapx_features_EQ>,
- AliasArgs<["egpr","push2pop2","ppx","ndd","ccmp","nf","zu"]>,
- Group<m_x86_Features_Group>;
-def mno_apxf : Flag<["-"], "mno-apxf">, Alias<mno_apx_features_EQ>,
- AliasArgs<["egpr","push2pop2","ppx","ndd","ccmp","nf","zu"]>,
- Group<m_x86_Features_Group>;
+def mapxf : Flag<["-"], "mapxf">, Group<m_x86_Features_Group>;
+def mno_apxf : Flag<["-"], "mno-apxf">, Group<m_x86_Features_Group>;
def mapx_inline_asm_use_gpr32 : Flag<["-"], "mapx-inline-asm-use-gpr32">, Group<m_Group>,
HelpText<"Enable use of GPR32 in inline assembly for APX">;
} // let Flags = [TargetSpecific]
diff --git a/clang/lib/Basic/Targets/X86.cpp b/clang/lib/Basic/Targets/X86.cpp
index f00d435937b92..f0a1874be8111 100644
--- a/clang/lib/Basic/Targets/X86.cpp
+++ b/clang/lib/Basic/Targets/X86.cpp
@@ -164,6 +164,11 @@ bool X86TargetInfo::initFeatureMap(
for (auto &F : CPUFeatures)
setFeatureEnabled(Features, F, true);
+ if (Features.lookup("egpr") && getTriple().isOSWindows()) {
+ setFeatureEnabled(Features, "push2pop2", false);
+ setFeatureEnabled(Features, "ppx", false);
+ }
+
std::vector<std::string> UpdatedFeaturesVec;
for (const auto &Feature : FeaturesVec) {
// Expand general-regs-only to -x86, -mmx and -sse
@@ -967,7 +972,7 @@ void X86TargetInfo::getTargetDefines(const LangOptions &Opts,
Builder.defineMacro("__CF__");
if (HasZU)
Builder.defineMacro("__ZU__");
- if (HasEGPR && HasPush2Pop2 && HasPPX && HasNDD && HasCCMP && HasNF && HasZU)
+ if (HasEGPR && HasNDD && HasCCMP && HasNF && HasZU)
Builder.defineMacro("__APX_F__");
if (HasEGPR && HasInlineAsmUseGPR32)
Builder.defineMacro("__APX_INLINE_ASM_USE_GPR32__");
diff --git a/clang/lib/Driver/ToolChains/Arch/X86.cpp b/clang/lib/Driver/ToolChains/Arch/X86.cpp
index d6e6657c521f0..7a0dea030615d 100644
--- a/clang/lib/Driver/ToolChains/Arch/X86.cpp
+++ b/clang/lib/Driver/ToolChains/Arch/X86.cpp
@@ -252,14 +252,33 @@ void x86::getX86TargetFeatures(const Driver &D, const llvm::Triple &Triple,
D.Diag(diag::err_drv_unsupported_opt_for_target)
<< A->getSpelling() << Triple.getTriple();
- if (A->getOption().matches(options::OPT_mapx_features_EQ) ||
+ if (IsNegative)
+ Name = Name.substr(3);
+ if (A->getOption().matches(options::OPT_mapxf) ||
+ A->getOption().matches(options::OPT_mno_apxf) ||
+ A->getOption().matches(options::OPT_mapx_features_EQ) ||
A->getOption().matches(options::OPT_mno_apx_features_EQ)) {
if (Not64Bit && !IsNegative)
D.Diag(diag::err_drv_unsupported_opt_for_target)
- << StringRef(A->getSpelling().str() + "|-mapxf")
+ << StringRef("-mapx-features=|-mapxf")
<< Triple.getTriple();
+ if (Name == "apxf") {
+ if (IsNegative) {
+ Features.insert(Features.end(),
+ {"-egpr", "-ndd", "-ccmp", "-nf", "-zu"});
+ if (!Triple.isOSWindows())
+ Features.insert(Features.end(), {"-push2pop2", "-ppx"});
+ } else {
+ Features.insert(Features.end(),
+ {"+egpr", "+ndd", "+ccmp", "+nf", "+zu"});
+ if (!Triple.isOSWindows())
+ Features.insert(Features.end(), {"+push2pop2", "+ppx"});
+ }
+ continue;
+ }
+
for (StringRef Value : A->getValues()) {
if (Value != "egpr" && Value != "push2pop2" && Value != "ppx" &&
Value != "ndd" && Value != "ccmp" && Value != "nf" &&
@@ -272,8 +291,6 @@ void x86::getX86TargetFeatures(const Driver &D, const llvm::Triple &Triple,
}
continue;
}
- if (IsNegative)
- Name = Name.substr(3);
Features.push_back(Args.MakeArgString((IsNegative ? "-" : "+") + Name));
}
diff --git a/clang/test/Driver/cl-x86-flags.c b/clang/test/Driver/cl-x86-flags.c
index 84270aae35f7a..f85828b370d9e 100644
--- a/clang/test/Driver/cl-x86-flags.c
+++ b/clang/test/Driver/cl-x86-flags.c
@@ -222,6 +222,6 @@ void f(void) {
// RUN: %clang_cl --target=x86_64-pc-windows -mapxf -### -- 2>&1 %s | FileCheck -check-prefix=APXF %s
// RUN: %clang_cl --target=x86_64-pc-windows -mapxf -mno-apxf -### -- 2>&1 %s | FileCheck -check-prefix=NO-APXF %s
// RUN: %clang_cl --target=x86_64-pc-windows -mapx-features=egpr,push2pop2,ppx,ndd,ccmp,nf,cf,zu -### -- 2>&1 %s | FileCheck -check-prefix=APXALL %s
-// APXF: "-target-feature" "+egpr" "-target-feature" "+push2pop2" "-target-feature" "+ppx" "-target-feature" "+ndd" "-target-feature" "+ccmp" "-target-feature" "+nf" "-target-feature" "+zu"
-// NO-APXF: "-target-feature" "-egpr" "-target-feature" "-push2pop2" "-target-feature" "-ppx" "-target-feature" "-ndd" "-target-feature" "-ccmp" "-target-feature" "-nf" "-target-feature" "-zu"
+// APXF: "-target-feature" "+egpr" "-target-feature" "+ndd" "-target-feature" "+ccmp" "-target-feature" "+nf" "-target-feature" "+zu"
+// NO-APXF: "-target-feature" "-egpr" "-target-feature" "-ndd" "-target-feature" "-ccmp" "-target-feature" "-nf" "-target-feature" "-zu"
// APXALL: "-target-feature" "+egpr" "-target-feature" "+push2pop2" "-target-feature" "+ppx" "-target-feature" "+ndd" "-target-feature" "+ccmp" "-target-feature" "+nf" "-target-feature" "+cf" "-target-feature" "+zu"
diff --git a/clang/test/Driver/x86-target-features.c b/clang/test/Driver/x86-target-features.c
index f1660b1afb518..c0f2340d0f9fe 100644
--- a/clang/test/Driver/x86-target-features.c
+++ b/clang/test/Driver/x86-target-features.c
@@ -443,8 +443,8 @@
// RUN: %clang --target=x86_64-unknown-linux-gnu -mno-apxf -mapxf %s -### -o %t.o 2>&1 | FileCheck -check-prefix=APXF %s
// RUN: %clang --target=x86_64-unknown-linux-gnu -mapxf -mno-apxf %s -### -o %t.o 2>&1 | FileCheck -check-prefix=NO-APXF %s
//
-// APXF: "-target-feature" "+egpr" "-target-feature" "+push2pop2" "-target-feature" "+ppx" "-target-feature" "+ndd" "-target-feature" "+ccmp" "-target-feature" "+nf" "-target-feature" "+zu"
-// NO-APXF: "-target-feature" "-egpr" "-target-feature" "-push2pop2" "-target-feature" "-ppx" "-target-feature" "-ndd" "-target-feature" "-ccmp" "-target-feature" "-nf" "-target-feature" "-zu"
+// APXF: "-target-feature" "+egpr" "-target-feature" "+ndd" "-target-feature" "+ccmp" "-target-feature" "+nf" "-target-feature" "+zu" "-target-feature" "+push2pop2" "-target-feature" "+ppx"
+// NO-APXF: "-target-feature" "-egpr" "-target-feature" "-ndd" "-target-feature" "-ccmp" "-target-feature" "-nf" "-target-feature" "-zu" "-target-feature" "-push2pop2" "-target-feature" "-ppx"
// RUN: %clang --target=x86_64-unknown-linux-gnu -mapx-features=egpr %s -### -o %t.o 2>&1 | FileCheck -check-prefix=EGPR %s
// RUN: %clang --target=x86_64-unknown-linux-gnu -mapx-features=push2pop2 %s -### -o %t.o 2>&1 | FileCheck -check-prefix=PUSH2POP2 %s
diff --git a/llvm/lib/Target/X86/X86Subtarget.cpp b/llvm/lib/Target/X86/X86Subtarget.cpp
index 61f288ffb909b..4e2e98410f325 100644
--- a/llvm/lib/Target/X86/X86Subtarget.cpp
+++ b/llvm/lib/Target/X86/X86Subtarget.cpp
@@ -257,6 +257,9 @@ void X86Subtarget::initSubtargetFeatures(StringRef CPU, StringRef TuneCPU,
std::string FullFS = X86_MC::ParseX86Triple(TargetTriple);
assert(!FullFS.empty() && "Failed to parse X86 triple");
+ if (TargetTriple.isOSWindows())
+ FullFS += ",-push2pop2,-ppx";
+
if (!FS.empty())
FullFS = (Twine(FullFS) + "," + FS).str();
diff --git a/llvm/lib/TargetParser/Host.cpp b/llvm/lib/TargetParser/Host.cpp
index 5d4fa2c88153c..7b1af1779a24a 100644
--- a/llvm/lib/TargetParser/Host.cpp
+++ b/llvm/lib/TargetParser/Host.cpp
@@ -2167,8 +2167,10 @@ StringMap<bool> sys::getHostCPUFeatures() {
bool HasAVX10 = HasLeaf7Subleaf1 && ((EDX >> 19) & 1);
bool HasAPXF = HasLeaf7Subleaf1 && ((EDX >> 21) & 1) && HasAPXSave;
Features["egpr"] = HasAPXF;
+#ifndef _WIN32
Features["push2pop2"] = HasAPXF;
Features["ppx"] = HasAPXF;
+#endif
Features["ndd"] = HasAPXF;
Features["ccmp"] = HasAPXF;
Features["nf"] = HasAPXF;
diff --git a/llvm/test/CodeGen/X86/apx/push2-pop2-cfi-seh.ll b/llvm/test/CodeGen/X86/apx/push2-pop2-cfi-seh.ll
index d6d4db3509103..071b297b49dc1 100644
--- a/llvm/test/CodeGen/X86/apx/push2-pop2-cfi-seh.ll
+++ b/llvm/test/CodeGen/X86/apx/push2-pop2-cfi-seh.ll
@@ -2,7 +2,9 @@
; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu | FileCheck %s --check-prefix=LIN-REF
; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -mattr=+push2pop2 | FileCheck %s --check-prefix=LIN
; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -mattr=+push2pop2,+ppx | FileCheck %s --check-prefix=LIN-PPX
+; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -mcpu=diamondrapids | FileCheck %s --check-prefix=LIN-PPX
; RUN: llc < %s -mtriple=x86_64-windows-msvc | FileCheck %s --check-prefix=WIN-REF
+; RUN: llc < %s -mtriple=x86_64-windows-msvc -mcpu=diamondrapids | FileCheck %s --check-prefix=WIN-REF
; RUN: llc < %s -mtriple=x86_64-windows-msvc -mattr=+push2pop2 | FileCheck %s --check-prefix=WIN
; RUN: llc < %s -mtriple=x86_64-windows-msvc -mattr=+push2pop2,+ppx | FileCheck %s --check-prefix=WIN-PPX
|
|
✅ With the latest revision this PR passed the C/C++ code formatter. |
RKSimon
reviewed
Jan 27, 2026
| @@ -2167,8 +2167,10 @@ StringMap<bool> sys::getHostCPUFeatures() { | |||
| bool HasAVX10 = HasLeaf7Subleaf1 && ((EDX >> 19) & 1); | |||
| bool HasAPXF = HasLeaf7Subleaf1 && ((EDX >> 21) & 1) && HasAPXSave; | |||
| Features["egpr"] = HasAPXF; | |||
| #ifndef _WIN32 | |||
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Comments? Is there a plan to support this in the future?
Ideally we wouldn't filter the host cpu features by OS like this - but I'm not sure what alternatives there are?
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Done. I think so, but it's not clear to me now. I think it's fine here now. Host means build and run must be on the same machine with the same OS (notes APXSave is OS dependent already). So we don't worry about it's enabled or disabled incorrectly.
RKSimon
reviewed
Jan 28, 2026
| D.Diag(diag::err_drv_unsupported_opt_for_target) | ||
| << StringRef(A->getSpelling().str() + "|-mapxf") | ||
| << Triple.getTriple(); | ||
| << StringRef("-mapx-features=|-mapxf") << Triple.getTriple(); |
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It was checked together. I split them now.
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Jan 28, 2026
| if (HasZU) | ||
| Builder.defineMacro("__ZU__"); | ||
| if (HasEGPR && HasPush2Pop2 && HasPPX && HasNDD && HasCCMP && HasNF && HasZU) | ||
| if (HasEGPR && HasNDD && HasCCMP && HasNF && HasZU) |
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GCC is a bit different. They don't define and check single features: https://godbolt.org/z/6esWPovj7
I changed to check OS to match GCC as possible.
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Ping? |
RKSimon
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Feb 2, 2026
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LGTM - but I'm not very familiar with APX - if you want to backport this to 22.x I'd be more comfortable with a second reviewer
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/cherry-pick 2f3935b |
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|
/pull-request #179404 |
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Feb 3, 2026
The PUSH2/POP2/PPX instructions for APX require updates to the Microsoft Windows OS x64 calling convention documented at https://learn.microsoft.com/en-us/cpp/build/exception-handling-x64?view=msvc-170 due to lack of suitable unwinder opcodes that can support APX PUSH2/POP2/PPX. The PR request disables this support by default for code robustness; workloads that choose to explicitly enable this support can change the default behavior by explicitly specifying the flag options that enable this support e.g. for experimentation or code paths that do not need unwinder support. (cherry picked from commit 2f3935b)
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The PUSH2/POP2/PPX instructions for APX require updates to the Microsoft Windows OS x64 calling convention documented at https://learn.microsoft.com/en-us/cpp/build/exception-handling-x64?view=msvc-170 due to lack of suitable unwinder opcodes that can support APX PUSH2/POP2/PPX.
The PR request disables this support by default for code robustness; workloads that choose to explicitly enable this support can change the default behavior by explicitly specifying the flag options that enable this support e.g. for experimentation or code paths that do not need unwinder support.