Add patch to force nomadd4 on mips, update changelog

debian/changelog

@@ -1,8 +1,14 @@
 llvm-toolchain-10 (1:10.0.1~+rc4-2) UNRELEASED; urgency=medium
 
+  [ Samuel Thibault ]
   * patches/hurd/hurd-cxx-paths.diff: Refresh, some of the factorization was
     backported from 11 to 10.
 
+  [ Gianfranco Costamagna ]
+  * debian/patches/mips-force-nomadd4.patch: Apply and rebase patch to disable
+    nomadd4 on mips* (Closes: #964989)
+    - thanks Yunqiang Su <wzssyqa@gmail.com> for the patch
+
  -- Samuel Thibault <sthibault@debian.org>  Tue, 07 Jul 2020 18:39:08 +0200
 
 llvm-toolchain-10 (1:10.0.1~+rc4-1) unstable; urgency=medium

debian/patches/mips-force-nomadd4.patch

@@ -0,0 +1,92 @@
+The MIPS port aims to support the Loongson 3 family of CPUs in addition
+of the other MIPS CPUs. On the Loongson 3 family the MADD4 instructions
+are fused, while they are not fused on the other MIPS CPUs. In order to
+support both, we have to disabled those instructions.
+
+For that, the patch below basically corresponds to the --with-madd4=no
+used on the GCC side.
+
+Index: llvm-toolchain-10-10.0.1~+rc4/clang/lib/Basic/Targets/Mips.h
+===================================================================
+--- llvm-toolchain-10-10.0.1~+rc4.orig/clang/lib/Basic/Targets/Mips.h
++++ llvm-toolchain-10-10.0.1~+rc4/clang/lib/Basic/Targets/Mips.h
+@@ -332,6 +332,8 @@
+         HasMSA = true;
+       else if (Feature == "+nomadd4")
+         DisableMadd4 = true;
++      else if (Feature == "-nomadd4")
++        DisableMadd4 = false;
+       else if (Feature == "+fp64")
+         FPMode = FP64;
+       else if (Feature == "-fp64")
+Index: llvm-toolchain-10-10.0.1~+rc4/llvm/lib/Target/Mips/MipsSubtarget.cpp
+===================================================================
+--- llvm-toolchain-10-10.0.1~+rc4.orig/llvm/lib/Target/Mips/MipsSubtarget.cpp
++++ llvm-toolchain-10-10.0.1~+rc4/llvm/lib/Target/Mips/MipsSubtarget.cpp
+@@ -79,7 +79,7 @@
+       InMips16Mode(false), InMips16HardFloat(Mips16HardFloat),
+       InMicroMipsMode(false), HasDSP(false), HasDSPR2(false), HasDSPR3(false),
+       AllowMixed16_32(Mixed16_32 | Mips_Os16), Os16(Mips_Os16), HasMSA(false),
+-      UseTCCInDIV(false), HasSym32(false), HasEVA(false), DisableMadd4(false),
++      UseTCCInDIV(false), HasSym32(false), HasEVA(false), DisableMadd4(true),
+       HasMT(false), HasCRC(false), HasVirt(false), HasGINV(false),
+       UseIndirectJumpsHazard(false), StackAlignOverride(StackAlignOverride),
+       TM(TM), TargetTriple(TT), TSInfo(),
+@@ -91,6 +91,9 @@
+   if (MipsArchVersion == MipsDefault)
+     MipsArchVersion = Mips32;
+ 
++  if (hasMips32r6() || hasMips64r6())
++    DisableMadd4 = false;
++
+   // Don't even attempt to generate code for MIPS-I and MIPS-V. They have not
+   // been tested and currently exist for the integrated assembler only.
+   if (MipsArchVersion == Mips1)
+@@ -238,6 +241,7 @@
+ MipsSubtarget::initializeSubtargetDependencies(StringRef CPU, StringRef FS,
+                                                const TargetMachine &TM) {
+   std::string CPUName = MIPS_MC::selectMipsCPU(TM.getTargetTriple(), CPU);
++  SubtargetFeatures Features(FS);
+ 
+   // Parse features string.
+   ParseSubtargetFeatures(CPUName, FS);
+@@ -260,6 +264,13 @@
+     report_fatal_error("64-bit code requested on a subtarget that doesn't "
+                        "support it!");
+ 
++  for (const std::string &Feature : Features.getFeatures()) {
++    if (Feature == "+nomadd4")
++      DisableMadd4 = true;
++    else if (Feature == "-nomadd4")
++      DisableMadd4 = false;
++  }
++
+   return *this;
+ }
+ 
+Index: llvm-toolchain-10-10.0.1~+rc4/llvm/lib/Target/Mips/Mips.td
+===================================================================
+--- llvm-toolchain-10-10.0.1~+rc4.orig/llvm/lib/Target/Mips/Mips.td
++++ llvm-toolchain-10-10.0.1~+rc4/llvm/lib/Target/Mips/Mips.td
+@@ -205,7 +205,7 @@
+                                "UseTCCInDIV", "false",
+                                "Force the assembler to use trapping">;
+ 
+-def FeatureMadd4
++def FeatureNoMadd4
+     : SubtargetFeature<"nomadd4", "DisableMadd4", "true",
+                        "Disable 4-operand madd.fmt and related instructions">;
+ 
+Index: llvm-toolchain-10-10.0.1~+rc4/llvm/lib/Target/Mips/MipsInstrInfo.td
+===================================================================
+--- llvm-toolchain-10-10.0.1~+rc4.orig/llvm/lib/Target/Mips/MipsInstrInfo.td
++++ llvm-toolchain-10-10.0.1~+rc4/llvm/lib/Target/Mips/MipsInstrInfo.td
+@@ -242,7 +242,7 @@
+ def HasMSA : Predicate<"Subtarget->hasMSA()">,
+              AssemblerPredicate<"FeatureMSA">;
+ def HasMadd4 : Predicate<"!Subtarget->disableMadd4()">,
+-               AssemblerPredicate<"!FeatureMadd4">;
++               AssemblerPredicate<"!FeatureNoMadd4">;
+ def HasMT  : Predicate<"Subtarget->hasMT()">,
+              AssemblerPredicate<"FeatureMT">;
+ def UseIndirectJumpsHazard : Predicate<"Subtarget->useIndirectJumpsHazard()">,

debian/patches/series

@@ -146,3 +146,4 @@ no-cgi.patch
 ubuntu-groovy.diff
 clang_vendor_pass_stage2.diff
 remove-trailing-space-version.diff
+mips-force-nomadd4.patch