[mips] Add warnings for using dsp and msa flags with inappropriate MIPS ISA revisions

[mstojanovic]

Summary

Dsp and dspr2 require MIPS revision 2, while msa requires revision 5. Adding warnings for cases when these flags are used with earlier revision.

[mstojanovic]

Fixed formatting.

[sdardis]

lib/Target/Mips/MipsSubtarget.cpp

130–131

Hoist this to a static member variable of MipsSubtarget, rather than a function static variable.

132–164

Change the message of "the 'msa' extension" to "the 'msa' ASE".

145–149

Change the message of "the 'msa' extension" to "the 'msa' ASE".

155

See my comment about DspWarningPrinted.

test/CodeGen/Mips/dsp_msa_warning.ll

3–30

Check prefixes should be in capital letters, to ensure they stand out.

[mstojanovic]

Addressed review comments.

[sdardis]

LGTM with a title fix: inapropriate MIPS revision-> inappropriate MIPS ISA revisions

lib/Target/Mips/MipsSubtarget.cpp

MipsSubtarget::MipsSubtarget(const Triple &TT, StringRef CPU, StringRef FS,
 
   // Set UseSmallSection.
   UseSmallSection = GPOpt;
   if (!NoABICalls && GPOpt) {
     errs() << "warning: cannot use small-data accesses for '-mabicalls'"
            << "\n";
     UseSmallSection = false;
   }
+
+  // Used to avoid printing dsp warnings multiple times.
+  static bool DspWarningPrinted = false;
+
+  if(hasDSPR2() && !DspWarningPrinted) {
+    if(hasMips64() && !hasMips64r2()) {
+      errs() << "warning: the 'dspr2' extension requires MIPS64 revision 2 or "
+             << "greater\n";
+      DspWarningPrinted = true;
+    } else if(hasMips32() && !hasMips32r2()) {
+      errs() << "warning: the 'dspr2' extension requires MIPS32 revision 2 or "
+             << "greater\n";
+      DspWarningPrinted = true;
+    }
+  } else if(hasDSP() && !DspWarningPrinted) {
+    if(hasMips64() && !hasMips64r2()) {
+      errs() << "warning: the 'dsp' extension requires MIPS64 revision 2 or "
+             << "greater\n";
+      DspWarningPrinted = true;
+    } else if(hasMips32() && !hasMips32r2()) {
+      errs() << "warning: the 'dsp' extension requires MIPS32 revision 2 or "
+             << "greater\n";
+      DspWarningPrinted = true;
+    }
+  }
+
+  // Used to avoid printing msa warnings multiple times.
+  static bool MSAWarningPrinted = false;
+  if(hasMSA() && !MSAWarningPrinted) {
+    if(hasMips64() && !hasMips64r5()) {
+      errs() << "warning: the 'msa' extension requires MIPS64 revision 5 or "
+             << "greater\n";
+      MSAWarningPrinted = true;
+    } else if(hasMips32() && !hasMips32r5()) {
+      errs() << "warning: the 'msa' extension requires MIPS32 revision 5 or "
+             << "greater\n";
+      MSAWarningPrinted = true;
+    }
+  }
 }
 
 bool MipsSubtarget::isPositionIndependent() const {
   return TM.isPositionIndependent();
 }
 
 /// This overrides the PostRAScheduler bit in the SchedModel for any CPU.
 bool MipsSubtarget::enablePostRAScheduler() const { return true; }

test/CodeGen/Mips/dsp_msa_warning.ll

+; RUN: llc -march=mips -mattr=+mips32r2 -mattr=+msa -mattr=+fp64 < %s 2>&1 | FileCheck %s -check-prefix=msa_32
+; RUN: llc -march=mips64 -mattr=+mips64r2 -mattr=+msa < %s 2>&1 | FileCheck %s  -check-prefix=msa_64
+; RUN: llc -march=mips -mattr=+mips32 -mattr=+dspr2 < %s 2>&1| FileCheck %s -check-prefix=dspr2_32
+; RUN: llc -march=mips64 -mattr=+mips64 -mattr=+dspr2 < %s 2>&1 | FileCheck %s -check-prefix=dspr2_64
+; RUN: llc -march=mips -mattr=+mips32 -mattr=+dsp < %s 2>&1 | FileCheck %s -check-prefix=dsp_32
+; RUN: llc -march=mips64 -mattr=+mips64 -mattr=+dsp < %s 2>&1 | FileCheck %s  -check-prefix=dsp_64
+; RUN: llc -march=mips -mattr=+mips32r2 -mattr=+dspr2 < %s 2>&1 | FileCheck %s  -check-prefix=dspr2_32_no_warning
+; RUN: llc -march=mips64 -mattr=+mips64r3 -mattr=+dspr2 < %s  2>&1 | FileCheck %s -check-prefix=dspr2_64_no_warning
+; RUN: llc -march=mips -mattr=+mips32r5 -mattr=+dsp < %s 2>&1 | FileCheck %s -check-prefix=dsp_32_no_warning
+; RUN: llc -march=mips64 -mattr=+mips64r2 -mattr=+dsp < %s 2>&1 | FileCheck %s -check-prefix=dsp_64_no_warning
+
+; msa_32: warning: the 'msa' extension requires MIPS32 revision 5 or greater
+; msa_64: warning: the 'msa' extension requires MIPS64 revision 5 or greater
+; dspr2_32: warning: the 'dspr2' extension requires MIPS32 revision 2 or greater
+; dspr2_64: warning: the 'dspr2' extension requires MIPS64 revision 2 or greater
+; dsp_32: warning: the 'dsp' extension requires MIPS32 revision 2 or greater
+; dsp_64: warning: the 'dsp' extension requires MIPS64 revision 2 or greater
+; dspr2_32_no_warning-NOT: warning: the 'dspr2' extension requires MIPS32 revision 2 or greater
+; dspr2_64_no_warning-NOT: warning: the 'dspr2' extension requires MIPS64 revision 2 or greater
+; dsp_32_no_warning-NOT: warning: the 'dsp' extension requires MIPS32 revision 2 or greater
+; dsp_64_no_warning-NOT: warning: the 'dsp' extension requires MIPS64 revision 2 or greater