[X86] Support EGPR for inline assembly. #92338

FreddyLeaf · 2024-05-16T03:13:08Z

"jR": explicitly enables EGPR
"r", "l", "q": enables/disables EGPR w/wo -mapx-inline-asm-use-gpr32
"jr": explicitly enables GPR with -mapx-inline-asm-use-gpr32
-mapx-inline-asm-use-gpr32 will also define a new macro:
__APX_INLINE_ASM_USE_GPR32__

GCC patches:
https://gcc.gnu.org/pipermail/gcc-patches/2023-September/631183.html
https://gcc.gnu.org/pipermail/gcc-patches/2023-September/631186.html
[PATCH v2] x86: Define APX_INLINE_ASM_USE_GPR32 (gnu.org)

Reference: https://gcc.godbolt.org/z/nPPvbY6r4

"jR": explictly enables EGPR "r": enables/disables EGPR w/wo -mapx-inline-asm-use-gpr32 -mapx-inline-asm-use-gpr32 will also define a new Macro: __APX_INLINE_ASM_USE_GPR32__

llvmbot · 2024-05-16T03:13:38Z

@llvm/pr-subscribers-llvm-ir
@llvm/pr-subscribers-backend-x86
@llvm/pr-subscribers-clang-driver

@llvm/pr-subscribers-clang

Author: Freddy Ye (FreddyLeaf)

Changes

"jR": explictly enables EGPR
"r": enables/disables EGPR w/wo -mapx-inline-asm-use-gpr32
-mapx-inline-asm-use-gpr32 will also define a new Macro:
APX_INLINE_ASM_USE_GPR32

Full diff: https://github.com/llvm/llvm-project/pull/92338.diff

10 Files Affected:

(modified) clang/include/clang/Driver/Options.td (+2)
(modified) clang/lib/Basic/Targets/X86.cpp (+26)
(modified) clang/lib/Basic/Targets/X86.h (+1)
(modified) clang/lib/Driver/ToolChains/Arch/X86.cpp (+2)
(added) clang/test/Driver/x86-apx-inline-asm-use-gpr32.cpp (+3)
(modified) clang/test/Preprocessor/x86_target_features.c (+3)
(modified) llvm/lib/Target/X86/X86.td (+3)
(modified) llvm/lib/Target/X86/X86ISelLowering.cpp (+52-5)
(added) llvm/test/CodeGen/X86/inline-asm-jR-constraint.ll (+19)
(added) llvm/test/CodeGen/X86/inline-asm-r-constraint.ll (+16)

diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index 73a2518480e9b..20a7c482bbf06 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -6281,6 +6281,8 @@ def mno_apx_features_EQ : CommaJoined<["-"], "mno-apx-features=">, Group<m_x86_F
 // we will add it to -mapxf.
 def mapxf : Flag<["-"], "mapxf">, Alias<mapx_features_EQ>, AliasArgs<["egpr","push2pop2","ppx", "ndd"]>;
 def mno_apxf : Flag<["-"], "mno-apxf">, Alias<mno_apx_features_EQ>, AliasArgs<["egpr","push2pop2","ppx","ndd"]>;
+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]
 
 // VE feature flags
diff --git a/clang/lib/Basic/Targets/X86.cpp b/clang/lib/Basic/Targets/X86.cpp
index 67e2126cf766b..9e61b6e6d6441 100644
--- a/clang/lib/Basic/Targets/X86.cpp
+++ b/clang/lib/Basic/Targets/X86.cpp
@@ -450,6 +450,8 @@ bool X86TargetInfo::handleTargetFeatures(std::vector<std::string> &Features,
       HasFullBFloat16 = true;
     } else if (Feature == "+egpr") {
       HasEGPR = true;
+    } else if (Feature == "+inline-asm-use-gpr32") {
+      HasInlineAsmUseGPR32 = true;
     } else if (Feature == "+push2pop2") {
       HasPush2Pop2 = true;
     } else if (Feature == "+ppx") {
@@ -974,6 +976,8 @@ void X86TargetInfo::getTargetDefines(const LangOptions &Opts,
   // Condition here is aligned with the feature set of mapxf in Options.td
   if (HasEGPR && HasPush2Pop2 && HasPPX && HasNDD)
     Builder.defineMacro("__APX_F__");
+  if (HasInlineAsmUseGPR32)
+    Builder.defineMacro("__APX_INLINE_ASM_USE_GPR32__");
 
   // Each case falls through to the previous one here.
   switch (SSELevel) {
@@ -1493,6 +1497,15 @@ bool X86TargetInfo::validateAsmConstraint(
   case 'C': // SSE floating point constant.
   case 'G': // x87 floating point constant.
     return true;
+  case 'j':
+    Name++;
+    switch (*Name) {
+    default:
+      return false;
+    case 'R':
+      Info.setAllowsRegister();
+      return true;
+    }
   case '@':
     // CC condition changes.
     if (auto Len = matchAsmCCConstraint(Name)) {
@@ -1764,6 +1777,19 @@ std::string X86TargetInfo::convertConstraint(const char *&Constraint) const {
       // to the next constraint.
       return std::string("^") + std::string(Constraint++, 2);
     }
+  case 'j':
+    switch (Constraint[1]) {
+    default:
+      // Break from inner switch and fall through (copy single char),
+      // continue parsing after copying the current constraint into
+      // the return string.
+      break;
+    case 'R':
+      // "^" hints llvm that this is a 2 letter constraint.
+      // "Constraint++" is used to promote the string iterator
+      // to the next constraint.
+      return std::string("^") + std::string(Constraint++, 2);
+    }
     [[fallthrough]];
   default:
     return std::string(1, *Constraint);
diff --git a/clang/lib/Basic/Targets/X86.h b/clang/lib/Basic/Targets/X86.h
index c14e4d5f433d8..69c68ee80f3ba 100644
--- a/clang/lib/Basic/Targets/X86.h
+++ b/clang/lib/Basic/Targets/X86.h
@@ -174,6 +174,7 @@ class LLVM_LIBRARY_VISIBILITY X86TargetInfo : public TargetInfo {
   bool HasNDD = false;
   bool HasCCMP = false;
   bool HasCF = false;
+  bool HasInlineAsmUseGPR32 = false;
 
 protected:
   llvm::X86::CPUKind CPU = llvm::X86::CK_None;
diff --git a/clang/lib/Driver/ToolChains/Arch/X86.cpp b/clang/lib/Driver/ToolChains/Arch/X86.cpp
index 53e26a9f8e229..085ff4824a9b0 100644
--- a/clang/lib/Driver/ToolChains/Arch/X86.cpp
+++ b/clang/lib/Driver/ToolChains/Arch/X86.cpp
@@ -309,4 +309,6 @@ void x86::getX86TargetFeatures(const Driver &D, const llvm::Triple &Triple,
     Features.push_back("+prefer-no-gather");
   if (Args.hasArg(options::OPT_mno_scatter))
     Features.push_back("+prefer-no-scatter");
+  if (Args.hasArg(options::OPT_mapx_inline_asm_use_gpr32))
+    Features.push_back("+inline-asm-use-gpr32");
 }
diff --git a/clang/test/Driver/x86-apx-inline-asm-use-gpr32.cpp b/clang/test/Driver/x86-apx-inline-asm-use-gpr32.cpp
new file mode 100644
index 0000000000000..a45140d96e66c
--- /dev/null
+++ b/clang/test/Driver/x86-apx-inline-asm-use-gpr32.cpp
@@ -0,0 +1,3 @@
+/// Tests -mapx-inline-asm-use-gpr32
+// RUN: %clang -target x86_64-unknown-linux-gnu -c -mapx-inline-asm-use-gpr32 -### %s 2>&1 | FileCheck --check-prefix=GPR32 %s
+// GPR32: "-target-feature" "+inline-asm-use-gpr32"
diff --git a/clang/test/Preprocessor/x86_target_features.c b/clang/test/Preprocessor/x86_target_features.c
index 5602c59158fe5..7fe19598fbd4e 100644
--- a/clang/test/Preprocessor/x86_target_features.c
+++ b/clang/test/Preprocessor/x86_target_features.c
@@ -811,3 +811,6 @@
 // NDD: #define __NDD__ 1
 // PPX: #define __PPX__ 1
 // PUSH2POP2: #define __PUSH2POP2__ 1
+
+// RUN: %clang -target x86_64-unknown-unknown -march=x86-64 -mapx-inline-asm-use-gpr32 -x c -E -dM -o - %s | FileCheck --check-prefixes=USEGPR32 %s
+// USEGPR32: #define __APX_INLINE_ASM_USE_GPR32__ 1
diff --git a/llvm/lib/Target/X86/X86.td b/llvm/lib/Target/X86/X86.td
index 9f5b58d78fcce..90a0c878a1101 100644
--- a/llvm/lib/Target/X86/X86.td
+++ b/llvm/lib/Target/X86/X86.td
@@ -353,6 +353,9 @@ def FeatureCCMP : SubtargetFeature<"ccmp", "HasCCMP", "true",
                                    "Support conditional cmp & test instructions">;
 def FeatureCF : SubtargetFeature<"cf", "HasCF", "true",
                                  "Support conditional faulting">;
+def FeatureUseGPR32InInlineAsm
+    : SubtargetFeature<"inline-asm-use-gpr32", "UseInlineAsmGPR32", "false",
+                       "Enable use of GPR32 in inline assembly for APX">;
 
 // Ivy Bridge and newer processors have enhanced REP MOVSB and STOSB (aka
 // "string operations"). See "REP String Enhancement" in the Intel Software
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 0410cc33ca337..2f381a3fc117c 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -57574,6 +57574,13 @@ X86TargetLowering::getConstraintType(StringRef Constraint) const {
       case '2':
         return C_RegisterClass;
       }
+    case 'j':
+      switch (Constraint[1]) {
+      default:
+        break;
+      case 'R':
+        return C_RegisterClass;
+      }
     }
   } else if (parseConstraintCode(Constraint) != X86::COND_INVALID)
     return C_Other;
@@ -57653,6 +57660,18 @@ X86TargetLowering::getSingleConstraintMatchWeight(
       break;
     }
     break;
+  case 'j':
+    if (StringRef(Constraint).size() != 2)
+      break;
+    switch (Constraint[1]) {
+    default:
+      return CW_Invalid;
+    case 'R':
+      if (CallOperandVal->getType()->isIntegerTy())
+        Wt = CW_SpecificReg;
+      break;
+    }
+    break;
   case 'v':
     if ((Ty->getPrimitiveSizeInBits() == 512) && Subtarget.hasAVX512())
       Wt = CW_Register;
@@ -58015,16 +58034,28 @@ X86TargetLowering::getRegForInlineAsmConstraint(const TargetRegisterInfo *TRI,
         return std::make_pair(0U, &X86::GR64_ABCDRegClass);
       break;
     case 'r':   // GENERAL_REGS
-    case 'l':   // INDEX_REGS
+    case 'l':   // INDEX_REGS{}
+      if (Subtarget.useInlineAsmGPR32()) {
+        if (VT == MVT::i8 || VT == MVT::i1)
+          return std::make_pair(0U, &X86::GR8_NOREX2RegClass);
+        if (VT == MVT::i16)
+          return std::make_pair(0U, &X86::GR16_NOREX2RegClass);
+        if (VT == MVT::i32 || VT == MVT::f32 ||
+            (!VT.isVector() && !Subtarget.is64Bit()))
+          return std::make_pair(0U, &X86::GR32_NOREX2RegClass);
+        if (VT != MVT::f80 && !VT.isVector())
+          return std::make_pair(0U, &X86::GR64_NOREX2RegClass);
+        break;
+      }
       if (VT == MVT::i8 || VT == MVT::i1)
-        return std::make_pair(0U, &X86::GR8_NOREX2RegClass);
+        return std::make_pair(0U, &X86::GR8RegClass);
       if (VT == MVT::i16)
-        return std::make_pair(0U, &X86::GR16_NOREX2RegClass);
+        return std::make_pair(0U, &X86::GR16RegClass);
       if (VT == MVT::i32 || VT == MVT::f32 ||
           (!VT.isVector() && !Subtarget.is64Bit()))
-        return std::make_pair(0U, &X86::GR32_NOREX2RegClass);
+        return std::make_pair(0U, &X86::GR32RegClass);
       if (VT != MVT::f80 && !VT.isVector())
-        return std::make_pair(0U, &X86::GR64_NOREX2RegClass);
+        return std::make_pair(0U, &X86::GR64RegClass);
       break;
     case 'R':   // LEGACY_REGS
       if (VT == MVT::i8 || VT == MVT::i1)
@@ -58248,6 +58279,22 @@ X86TargetLowering::getRegForInlineAsmConstraint(const TargetRegisterInfo *TRI,
       }
       break;
     }
+  } else if (Constraint.size() == 2 && Constraint[0] == 'j') {
+    switch (Constraint[1]) {
+      default:
+        break;
+      case 'R':
+        if (VT == MVT::i8 || VT == MVT::i1)
+          return std::make_pair(0U, &X86::GR8RegClass);
+        if (VT == MVT::i16)
+          return std::make_pair(0U, &X86::GR16RegClass);
+        if (VT == MVT::i32 || VT == MVT::f32 ||
+            (!VT.isVector() && !Subtarget.is64Bit()))
+          return std::make_pair(0U, &X86::GR32RegClass);
+        if (VT != MVT::f80 && !VT.isVector())
+          return std::make_pair(0U, &X86::GR64RegClass);
+        break;
+    }
   }
 
   if (parseConstraintCode(Constraint) != X86::COND_INVALID)
diff --git a/llvm/test/CodeGen/X86/inline-asm-jR-constraint.ll b/llvm/test/CodeGen/X86/inline-asm-jR-constraint.ll
new file mode 100644
index 0000000000000..2348e75433798
--- /dev/null
+++ b/llvm/test/CodeGen/X86/inline-asm-jR-constraint.ll
@@ -0,0 +1,19 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: not llc -mtriple=x86_64 %s 2>&1 | FileCheck %s --check-prefix=ERR
+; RUN: llc -mtriple=x86_64 -mattr=+egpr  < %s | FileCheck %s --check-prefix=EGPR
+; RUN: llc -mtriple=x86_64 -mattr=+egpr,+inline-asm-use-gpr32  < %s | FileCheck %s --check-prefix=EGPRUSEGPR32
+
+; ERR: error: inline assembly requires more registers than available
+
+define void @constraint_jR_test() nounwind "frame-pointer"="all" {
+; EGPR-LABEL: constraint_jR_test:
+; EGPR:    addq %r16, %rax
+;
+; EGPRUSEGPR32-LABEL: constraint_jR_test:
+; EGPRUSEGPR32:    addq %r16, %rax
+entry:
+  %reg = alloca i64, align 8
+  %0 = load i64, ptr %reg, align 8
+  call void asm sideeffect "add $0, %rax", "^jR,~{rax},~{rbx},~{rcx},~{rdx},~{rdi},~{rsi},~{r8},~{r9},~{r10},~{r11},~{r12},~{r13},~{r14},~{r15},~{dirflag},~{fpsr},~{flags}"(i64 %0)
+  ret void
+}
diff --git a/llvm/test/CodeGen/X86/inline-asm-r-constraint.ll b/llvm/test/CodeGen/X86/inline-asm-r-constraint.ll
new file mode 100644
index 0000000000000..158dcdf9be272
--- /dev/null
+++ b/llvm/test/CodeGen/X86/inline-asm-r-constraint.ll
@@ -0,0 +1,16 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: not llc -mtriple=x86_64 < %s 2>&1 | FileCheck %s --check-prefix=ERR
+; RUN: not llc -mtriple=x86_64 -mattr=+egpr < %s 2>&1 | FileCheck %s --check-prefix=ERR
+; RUN: llc -mtriple=x86_64 -mattr=+egpr,+inline-asm-use-gpr32 < %s | FileCheck %s --check-prefix=USEGPR32
+
+; ERR: error: inline assembly requires more registers than available
+
+define void @constraint_r_test() nounwind "frame-pointer"="all" {
+; USEGPR32-LABEL: constraint_r_test:
+; USEGPR32:    addq %r16, %rax
+entry:
+  %reg = alloca i64, align 8
+  %0 = load i64, ptr %reg, align 8
+  call void asm sideeffect "add $0, %rax", "r,~{rax},~{rbx},~{rcx},~{rdx},~{rdi},~{rsi},~{r8},~{r9},~{r10},~{r11},~{r12},~{r13},~{r14},~{r15},~{dirflag},~{fpsr},~{flags}"(i64 %0)
+  ret void
+}

github-actions · 2024-05-16T03:16:23Z

✅ With the latest revision this PR passed the C/C++ code formatter.

KanRobert · 2024-05-16T03:20:41Z

Please put the corresponding GCC links for your description

clang/lib/Basic/Targets/X86.cpp

FreddyLeaf · 2024-05-16T06:48:06Z

Please put the corresponding GCC links for your description

done.

FreddyLeaf · 2024-05-20T00:56:58Z

ping for review

llvm/test/CodeGen/X86/inline-asm-r-constraint.ll

jyknight · 2024-05-21T03:49:01Z

Please update the constraint code list https://llvm.org/docs/LangRef.html#supported-constraint-code-list with any new codes.

FreddyLeaf · 2024-05-21T05:27:58Z

Please update the constraint code list https://llvm.org/docs/LangRef.html#supported-constraint-code-list with any new codes.

Thanks reminding. Added in 4087704, pls help review.

llvm/test/CodeGen/X86/apx/inline-asm-jR-constraint.ll

llvm/test/CodeGen/X86/apx/inline-asm-r-constraint.ll

llvm/lib/Target/X86/X86ISelLowering.cpp

nickdesaulniers

someone with more knowledge about EGPR should approve this as well, but I'm happy with the code style for the additions.

llvm/docs/LangRef.rst

llvm/lib/Target/X86/X86ISelLowering.cpp

llvm/test/CodeGen/X86/apx/inline-asm-r-l-q-constraint.ll

llvm/test/CodeGen/X86/apx/inline-asm-jr-err-constraint.ll

llvm/test/CodeGen/X86/apx/inline-asm-jR-constraint.ll

llvm/test/CodeGen/X86/apx/asm-constraint.ll

llvm/lib/Target/X86/X86ISelLowering.cpp

llvm/test/CodeGen/X86/apx/inline-asm-jR-constraint.ll

llvm/test/CodeGen/X86/apx/inline-asm-jr-constraint.ll

KanRobert

LGTM

…92338)'

…' (#93777)

banach-space · 2024-05-30T08:54:12Z

Hi, thanks for this contribution. Sadly, it messes up my local checkout on MacOS (which is insensitive when it comes to files names). These files are problematic:

"asm-constraint-jR.ll" and "asm-constraint-jr.ll"

Please, could you rename them so that they are not identical on case-insensitive file systems?

RKSimon · 2024-05-30T09:50:04Z

@FreddyLeaf This is corrupting git checkouts on windows - please can you revert ?

Renames asm-constraint-jR.ll and asm-constraint-jR.ll - on case-insensitive files systems those are treated as one file. Originally introduced in llvm#92338.

banach-space · 2024-05-30T09:52:11Z

Should be fixed by #93794

Renames asm-constraint-jR.ll and asm-constraint-jR.ll - on case-insensitive files systems those are treated as one file. Originally introduced in #92338.

FreddyLeaf · 2024-05-31T00:53:23Z

Sorry, I was OOO, thanks for the fix!

[X86] Support EGPR for inline assembly.

41fbc18

"jR": explictly enables EGPR "r": enables/disables EGPR w/wo -mapx-inline-asm-use-gpr32 -mapx-inline-asm-use-gpr32 will also define a new Macro: __APX_INLINE_ASM_USE_GPR32__

FreddyLeaf requested review from KanRobert and phoebewang May 16, 2024 03:13

llvmbot added clang Clang issues not falling into any other category backend:X86 clang:driver 'clang' and 'clang++' user-facing binaries. Not 'clang-cl' clang:frontend Language frontend issues, e.g. anything involving "Sema" labels May 16, 2024

FreddyLeaf requested a review from RKSimon May 16, 2024 03:13

refine

c1daf20

KanRobert reviewed May 16, 2024

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clang/lib/Basic/Targets/X86.cpp Show resolved Hide resolved

FreddyLeaf added 2 commits May 16, 2024 14:52

clang-format

9f43b45

add egpr restric to the new option.

1fdd2f2

KanRobert reviewed May 20, 2024

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llvm/test/CodeGen/X86/inline-asm-r-constraint.ll Outdated Show resolved Hide resolved

address comments.

4d1ad30

address comments,

4087704

llvmbot added the llvm:ir label May 21, 2024

KanRobert requested review from jyknight and nickdesaulniers May 21, 2024 06:19

nickdesaulniers reviewed May 21, 2024

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llvm/test/CodeGen/X86/apx/inline-asm-jR-constraint.ll Outdated Show resolved Hide resolved

llvm/test/CodeGen/X86/apx/inline-asm-r-constraint.ll Outdated Show resolved Hide resolved

address comments

0bb6794

nickdesaulniers reviewed May 22, 2024

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llvm/lib/Target/X86/X86ISelLowering.cpp Outdated Show resolved Hide resolved

address

4a9bf69

nickdesaulniers approved these changes May 23, 2024

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