[X86] Remove what little support we had for MPX

-Deprecate -mmpx and -mno-mpx command line options
-Remove CPUID detection of mpx for -march=native
-Remove MPX from all CPUs
-Remove MPX preprocessor define

I've left the "mpx" string in the backend so we don't fail on old IR, but its not connected to anything.

gcc has also deprecated these command line options. https://www.phoronix.com/scan.php?page=news_item&px=GCC-Patch-To-Drop-MPX

Differential Revision: https://reviews.llvm.org/D66669

llvm-svn: 370393

8 files changed, 29 insertions, 29 deletions

diff --git a/llvm/docs/ReleaseNotes.rst b/llvm/docs/ReleaseNotes.rst
index c05804f2573..9e5273dea48 100644
--- a/llvm/docs/ReleaseNotes.rst
+++ b/llvm/docs/ReleaseNotes.rst
@@ -98,6 +98,10 @@ Changes to the AVR Target
 
  During this release ...
 
+* Deprecated the mpx feature flag for the Intel MPX instructions. There were no
+  intrinsics for this feature. This change only this effects the results
+  returned by getHostCPUFeatures on CPUs that implement the MPX instructions.
+
 Changes to the WebAssembly Target
 ---------------------------------
 
diff --git a/llvm/lib/Support/Host.cpp b/llvm/lib/Support/Host.cpp
index 836b363efd9..ef10b9689e8 100644
--- a/llvm/lib/Support/Host.cpp
+++ b/llvm/lib/Support/Host.cpp
@@ -1378,7 +1378,6 @@ bool sys::getHostCPUFeatures(StringMap<bool> &Features) {
   Features["bmi2"]       = HasLeaf7 && ((EBX >>  8) & 1);
   Features["invpcid"]    = HasLeaf7 && ((EBX >> 10) & 1);
   Features["rtm"]        = HasLeaf7 && ((EBX >> 11) & 1);
-  Features["mpx"]        = HasLeaf7 && ((EBX >> 14) & 1);
   // AVX512 is only supported if the OS supports the context save for it.
   Features["avx512f"]    = HasLeaf7 && ((EBX >> 16) & 1) && HasAVX512Save;
   Features["avx512dq"]   = HasLeaf7 && ((EBX >> 17) & 1) && HasAVX512Save;
diff --git a/llvm/lib/Target/X86/X86.td b/llvm/lib/Target/X86/X86.td
index b720dac307a..da7ec0ab74d 100644
--- a/llvm/lib/Target/X86/X86.td
+++ b/llvm/lib/Target/X86/X86.td
@@ -241,8 +241,11 @@ def FeatureCLDEMOTE  : SubtargetFeature<"cldemote", "HasCLDEMOTE", "true",
                                       "Enable Cache Demote">;
 def FeaturePTWRITE  : SubtargetFeature<"ptwrite", "HasPTWRITE", "true",
                                       "Support ptwrite instruction">;
-def FeatureMPX     : SubtargetFeature<"mpx", "HasMPX", "true",
-                                      "Support MPX instructions">;
+// FIXME: This feature is deprecated in 10.0 and should not be used for
+// anything, but removing it would break IR files that may contain it in a
+// target-feature attribute.
+def FeatureDeprecatedMPX : SubtargetFeature<"mpx", "DeprecatedHasMPX", "false",
+                                      "Deprecated. Support MPX instructions">;
 def FeatureLEAForSP : SubtargetFeature<"lea-sp", "UseLeaForSP", "true",
                                      "Use LEA for adjusting the stack pointer">;
 def FeatureSlowDivide32 : SubtargetFeature<"idivl-to-divb",
@@ -580,7 +583,6 @@ def ProcessorFeatures {
 
   // Skylake
   list<SubtargetFeature> SKLAdditionalFeatures = [FeatureAES,
-                                                  FeatureMPX,
                                                   FeatureXSAVEC,
                                                   FeatureXSAVES,
                                                   FeatureCLFLUSHOPT,
@@ -719,7 +721,6 @@ def ProcessorFeatures {
 
   // Goldmont
   list<SubtargetFeature> GLMAdditionalFeatures = [FeatureAES,
-                                                  FeatureMPX,
                                                   FeatureSHA,
                                                   FeatureRDSEED,
                                                   FeatureXSAVE,
diff --git a/llvm/lib/Target/X86/X86InstrInfo.td b/llvm/lib/Target/X86/X86InstrInfo.td
index 5a5df5edd6d..75958dd6c9e 100644
--- a/llvm/lib/Target/X86/X86InstrInfo.td
+++ b/llvm/lib/Target/X86/X86InstrInfo.td
@@ -940,7 +940,6 @@ def HasMOVDIR64B : Predicate<"Subtarget->hasMOVDIR64B()">;
 def HasPTWRITE   : Predicate<"Subtarget->hasPTWRITE()">;
 def FPStackf32   : Predicate<"!Subtarget->hasSSE1()">;
 def FPStackf64   : Predicate<"!Subtarget->hasSSE2()">;
-def HasMPX       : Predicate<"Subtarget->hasMPX()">;
 def HasSHSTK     : Predicate<"Subtarget->hasSHSTK()">;
 def HasCLFLUSHOPT : Predicate<"Subtarget->hasCLFLUSHOPT()">;
 def HasCLWB      : Predicate<"Subtarget->hasCLWB()">;
diff --git a/llvm/lib/Target/X86/X86InstrMPX.td b/llvm/lib/Target/X86/X86InstrMPX.td
index f7d931510fe..44ba071947c 100644
--- a/llvm/lib/Target/X86/X86InstrMPX.td
+++ b/llvm/lib/Target/X86/X86InstrMPX.td
@@ -12,16 +12,16 @@
 //
 //===----------------------------------------------------------------------===//
 
-// FIXME: Investigate a better scheduler class once MPX is used inside LLVM.
+// FIXME: Investigate a better scheduler class if MPX is ever used inside LLVM.
 let SchedRW = [WriteSystem] in {
 
 multiclass mpx_bound_make<bits<8> opc, string OpcodeStr> {
   def 32rm: I<opc, MRMSrcMem, (outs BNDR:$dst), (ins anymem:$src),
               OpcodeStr#"\t{$src, $dst|$dst, $src}", []>,
-              Requires<[HasMPX, Not64BitMode]>;
+              Requires<[Not64BitMode]>;
   def 64rm: I<opc, MRMSrcMem, (outs BNDR:$dst), (ins anymem:$src),
               OpcodeStr#"\t{$src, $dst|$dst, $src}", []>,
-              Requires<[HasMPX, In64BitMode]>;
+              Requires<[In64BitMode]>;
 }
 
 defm BNDMK : mpx_bound_make<0x1B, "bndmk">, XS;
@@ -29,17 +29,17 @@ defm BNDMK : mpx_bound_make<0x1B, "bndmk">, XS;
 multiclass mpx_bound_check<bits<8> opc, string OpcodeStr> {
   def 32rm: I<opc, MRMSrcMem, (outs), (ins  BNDR:$src1, anymem:$src2),
               OpcodeStr#"\t{$src2, $src1|$src1, $src2}", []>,
-              Requires<[HasMPX, Not64BitMode]>;
+              Requires<[Not64BitMode]>;
   def 64rm: I<opc, MRMSrcMem, (outs), (ins  BNDR:$src1, anymem:$src2),
               OpcodeStr#"\t{$src2, $src1|$src1, $src2}", []>,
-              Requires<[HasMPX, In64BitMode]>;
+              Requires<[In64BitMode]>;
 
   def 32rr: I<opc, MRMSrcReg, (outs), (ins  BNDR:$src1, GR32:$src2),
               OpcodeStr#"\t{$src2, $src1|$src1, $src2}", []>,
-              Requires<[HasMPX, Not64BitMode]>;
+              Requires<[Not64BitMode]>;
   def 64rr: I<opc, MRMSrcReg, (outs), (ins  BNDR:$src1, GR64:$src2),
               OpcodeStr#"\t{$src2, $src1|$src1, $src2}", []>,
-              Requires<[HasMPX, In64BitMode]>;
+              Requires<[In64BitMode]>;
 }
 defm BNDCL : mpx_bound_check<0x1A, "bndcl">, XS, NotMemoryFoldable;
 defm BNDCU : mpx_bound_check<0x1A, "bndcu">, XD, NotMemoryFoldable;
@@ -47,33 +47,31 @@ defm BNDCN : mpx_bound_check<0x1B, "bndcn">, XD, NotMemoryFoldable;
 
 def BNDMOVrr   : I<0x1A, MRMSrcReg, (outs BNDR:$dst), (ins BNDR:$src),
                   "bndmov\t{$src, $dst|$dst, $src}", []>, PD,
-                  Requires<[HasMPX]>, NotMemoryFoldable;
+                  NotMemoryFoldable;
 let mayLoad = 1 in {
 def BNDMOV32rm : I<0x1A, MRMSrcMem, (outs BNDR:$dst), (ins i64mem:$src),
                   "bndmov\t{$src, $dst|$dst, $src}", []>, PD,
-                  Requires<[HasMPX, Not64BitMode]>, NotMemoryFoldable;
+                  Requires<[Not64BitMode]>, NotMemoryFoldable;
 def BNDMOV64rm : I<0x1A, MRMSrcMem, (outs BNDR:$dst), (ins i128mem:$src),
                   "bndmov\t{$src, $dst|$dst, $src}", []>, PD,
-                  Requires<[HasMPX, In64BitMode]>, NotMemoryFoldable;
+                  Requires<[In64BitMode]>, NotMemoryFoldable;
 }
 let isCodeGenOnly = 1, ForceDisassemble = 1 in
 def BNDMOVrr_REV   : I<0x1B, MRMDestReg, (outs BNDR:$dst), (ins BNDR:$src),
                        "bndmov\t{$src, $dst|$dst, $src}", []>, PD,
-                       Requires<[HasMPX]>, NotMemoryFoldable;
+                       NotMemoryFoldable;
 let mayStore = 1 in {
 def BNDMOV32mr : I<0x1B, MRMDestMem, (outs), (ins i64mem:$dst, BNDR:$src),
                   "bndmov\t{$src, $dst|$dst, $src}", []>, PD,
-                  Requires<[HasMPX, Not64BitMode]>, NotMemoryFoldable;
+                  Requires<[Not64BitMode]>, NotMemoryFoldable;
 def BNDMOV64mr : I<0x1B, MRMDestMem, (outs), (ins i128mem:$dst, BNDR:$src),
                   "bndmov\t{$src, $dst|$dst, $src}", []>, PD,
-                  Requires<[HasMPX, In64BitMode]>, NotMemoryFoldable;
+                  Requires<[In64BitMode]>, NotMemoryFoldable;
 
 def BNDSTXmr:      I<0x1B, MRMDestMem, (outs), (ins anymem:$dst, BNDR:$src),
-                    "bndstx\t{$src, $dst|$dst, $src}", []>, PS,
-                    Requires<[HasMPX]>;
+                    "bndstx\t{$src, $dst|$dst, $src}", []>, PS;
 }
 let mayLoad = 1 in
 def BNDLDXrm:      I<0x1A, MRMSrcMem, (outs BNDR:$dst), (ins anymem:$src),
-                    "bndldx\t{$src, $dst|$dst, $src}", []>, PS,
-                    Requires<[HasMPX]>;
+                    "bndldx\t{$src, $dst|$dst, $src}", []>, PS;
 } // SchedRW
diff --git a/llvm/lib/Target/X86/X86Subtarget.h b/llvm/lib/Target/X86/X86Subtarget.h
index 9f73a821da2..46e777da15f 100644
--- a/llvm/lib/Target/X86/X86Subtarget.h
+++ b/llvm/lib/Target/X86/X86Subtarget.h
@@ -365,8 +365,8 @@ protected:
   /// Processor has AVX-512 vp2intersect instructions
   bool HasVP2INTERSECT = false;
 
-  /// Processor supports MPX - Memory Protection Extensions
-  bool HasMPX = false;
+  /// Deprecated flag for MPX instructions.
+  bool DeprecatedHasMPX = false;
 
   /// Processor supports CET SHSTK - Control-Flow Enforcement Technology
   /// using Shadow Stack
@@ -684,7 +684,6 @@ public:
   bool hasBF16() const { return HasBF16; }
   bool hasVP2INTERSECT() const { return HasVP2INTERSECT; }
   bool hasBITALG() const { return HasBITALG; }
-  bool hasMPX() const { return HasMPX; }
   bool hasSHSTK() const { return HasSHSTK; }
   bool hasCLFLUSHOPT() const { return HasCLFLUSHOPT; }
   bool hasCLWB() const { return HasCLWB; }
diff --git a/llvm/test/CodeGen/X86/ms-inline-asm-avx512.ll b/llvm/test/CodeGen/X86/ms-inline-asm-avx512.ll
index be60f5bca16..26b08287c05 100644
--- a/llvm/test/CodeGen/X86/ms-inline-asm-avx512.ll
+++ b/llvm/test/CodeGen/X86/ms-inline-asm-avx512.ll
@@ -20,5 +20,5 @@ entry:
 ; CHECK: movq    %rax, 7(%rsp)
 ; CHECK: retq
 
-attributes #0 = { noinline nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="skylake-avx512" "target-features"="+adx,+aes,+avx,+avx2,+avx512bw,+avx512cd,+avx512dq,+avx512f,+avx512vl,+bmi,+bmi2,+clflushopt,+clwb,+cx16,+f16c,+fma,+fsgsbase,+fxsr,+lzcnt,+mmx,+movbe,+mpx,+pclmul,+pku,+popcnt,+rdrnd,+rdseed,+rtm,+sgx,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+ssse3,+x87,+xsave,+xsavec,+xsaveopt,+xsaves" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #0 = { noinline nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="skylake-avx512" "target-features"="+adx,+aes,+avx,+avx2,+avx512bw,+avx512cd,+avx512dq,+avx512f,+avx512vl,+bmi,+bmi2,+clflushopt,+clwb,+cx16,+f16c,+fma,+fsgsbase,+fxsr,+lzcnt,+mmx,+movbe,+pclmul,+pku,+popcnt,+rdrnd,+rdseed,+rtm,+sgx,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+ssse3,+x87,+xsave,+xsavec,+xsaveopt,+xsaves" "unsafe-fp-math"="false" "use-soft-float"="false" }
 attributes #1 = { nounwind }
diff --git a/llvm/test/CodeGen/X86/vector-width-store-merge.ll b/llvm/test/CodeGen/X86/vector-width-store-merge.ll
index e316e08ebe1..9db3dbfb670 100644
--- a/llvm/test/CodeGen/X86/vector-width-store-merge.ll
+++ b/llvm/test/CodeGen/X86/vector-width-store-merge.ll
@@ -46,8 +46,8 @@ entry:
 ; Function Attrs: argmemonly nounwind
 declare void @llvm.memmove.p0i8.p0i8.i64(i8* nocapture, i8* nocapture readonly, i64, i1 immarg) #1
 
-attributes #0 = { nounwind uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "prefer-vector-width"="128" "stack-protector-buffer-size"="8" "target-cpu"="skylake-avx512" "target-features"="+adx,+aes,+avx,+avx2,+avx512bw,+avx512cd,+avx512dq,+avx512f,+avx512vl,+bmi,+bmi2,+clflushopt,+clwb,+cx16,+cx8,+f16c,+fma,+fsgsbase,+fxsr,+invpcid,+lzcnt,+mmx,+movbe,+mpx,+pclmul,+pku,+popcnt,+prfchw,+rdrnd,+rdseed,+sahf,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+ssse3,+x87,+xsave,+xsavec,+xsaveopt,+xsaves" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #0 = { nounwind uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "prefer-vector-width"="128" "stack-protector-buffer-size"="8" "target-cpu"="skylake-avx512" "target-features"="+adx,+aes,+avx,+avx2,+avx512bw,+avx512cd,+avx512dq,+avx512f,+avx512vl,+bmi,+bmi2,+clflushopt,+clwb,+cx16,+cx8,+f16c,+fma,+fsgsbase,+fxsr,+invpcid,+lzcnt,+mmx,+movbe,+pclmul,+pku,+popcnt,+prfchw,+rdrnd,+rdseed,+sahf,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+ssse3,+x87,+xsave,+xsavec,+xsaveopt,+xsaves" "unsafe-fp-math"="false" "use-soft-float"="false" }
 attributes #1 = { argmemonly nounwind }
-attributes #2 = { nounwind uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "prefer-vector-width"="256" "stack-protector-buffer-size"="8" "target-cpu"="skylake-avx512" "target-features"="+adx,+aes,+avx,+avx2,+avx512bw,+avx512cd,+avx512dq,+avx512f,+avx512vl,+bmi,+bmi2,+clflushopt,+clwb,+cx16,+cx8,+f16c,+fma,+fsgsbase,+fxsr,+invpcid,+lzcnt,+mmx,+movbe,+mpx,+pclmul,+pku,+popcnt,+prfchw,+rdrnd,+rdseed,+sahf,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+ssse3,+x87,+xsave,+xsavec,+xsaveopt,+xsaves" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #2 = { nounwind uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "prefer-vector-width"="256" "stack-protector-buffer-size"="8" "target-cpu"="skylake-avx512" "target-features"="+adx,+aes,+avx,+avx2,+avx512bw,+avx512cd,+avx512dq,+avx512f,+avx512vl,+bmi,+bmi2,+clflushopt,+clwb,+cx16,+cx8,+f16c,+fma,+fsgsbase,+fxsr,+invpcid,+lzcnt,+mmx,+movbe,+pclmul,+pku,+popcnt,+prfchw,+rdrnd,+rdseed,+sahf,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+ssse3,+x87,+xsave,+xsavec,+xsaveopt,+xsaves" "unsafe-fp-math"="false" "use-soft-float"="false" }
 
 !0 = !{i32 1, !"wchar_size", i32 4}