nodejs-15.1.0-ppc-fixes.patch

Fixes for older PowerPC targets.

* PPC64 big-endian ELFv1 ABI uses function descriptors, like AIX.

* Tell the code generator when we don't have the FP to int rounding
instructions (added in Power ISA v2.03) by not enabling them in the
MachineOperatorBuilder::Flags if we don't have a new enough CPU.

* Change minimum page size to 4KB for PPC. 64KB physical pages are a
newer feature that breaks some software, such as the nouveau driver.

* Change PPC CPU detection to use getauxval() for glibc 2.16 and newer,
and to correctly recognize all known Linux PowerPC platform types.
Cell BE is identified as PPC_G5; other CPUs with AltiVec as PPC_G4.
The new PPC_G3 type is used for all other CPUs without VMX/AltiVec.

* Add VMX feature for future VMX/AltiVec code generation. VMX is a
subset of VSX that's available on POWER6, G5, Cell, G4, and PA6T.
The newer VSX feature is only available on POWER7 and newer CPUs.

diff --git a/deps/v8/src/base/build_config.h b/deps/v8/src/base/build_config.h
index ad287c92..555363dc 100644
--- a/deps/v8/src/base/build_config.h
+++ b/deps/v8/src/base/build_config.h
@@ -203,11 +203,7 @@ constexpr int kReturnAddressStackSlotCount =
     V8_TARGET_ARCH_STORES_RETURN_ADDRESS_ON_STACK ? 1 : 0;
 
 // Number of bits to represent the page size for paged spaces.
-#if defined(V8_TARGET_ARCH_PPC) || defined(V8_TARGET_ARCH_PPC64)
-// PPC has large (64KB) physical pages.
-const int kPageSizeBits = 19;
-#else
+// Use 4KB for all targets. Not all PPC Linux kernels use 64KB pages.
 const int kPageSizeBits = 18;
-#endif
 
 #endif  // V8_BASE_BUILD_CONFIG_H_
diff --git a/deps/v8/src/base/cpu.cc b/deps/v8/src/base/cpu.cc
index bae1afe7..5c36caf8 100644
--- a/deps/v8/src/base/cpu.cc
+++ b/deps/v8/src/base/cpu.cc
@@ -676,8 +676,14 @@ CPU::CPU()
 
 #ifndef USE_SIMULATOR
 #if V8_OS_LINUX
+#if V8_GLIBC_PREREQ(2, 16)
+  // Read processor info from getauxval().
+  const char* auxv_cpu_type = reinterpret_cast<const char*>(getauxval(AT_PLATFORM));
+  icache_line_size_ = static_cast<int>(getauxval(AT_ICACHEBSIZE));
+  dcache_line_size_ = static_cast<int>(getauxval(AT_DCACHEBSIZE));
+#else
   // Read processor info from /proc/self/auxv.
-  char* auxv_cpu_type = nullptr;
+  const char* auxv_cpu_type = nullptr;
   FILE* fp = fopen("/proc/self/auxv", "r");
   if (fp != nullptr) {
 #if V8_TARGET_ARCH_PPC64
@@ -692,7 +698,7 @@ CPU::CPU()
       }
       switch (entry.a_type) {
         case AT_PLATFORM:
-          auxv_cpu_type = reinterpret_cast<char*>(entry.a_un.a_val);
+          auxv_cpu_type = reinterpret_cast<const char*>(entry.a_un.a_val);
           break;
         case AT_ICACHEBSIZE:
           icache_line_size_ = entry.a_un.a_val;
@@ -704,25 +710,36 @@ CPU::CPU()
     }
     fclose(fp);
   }
+#endif  // V8_GLIBC_PREREQ(2, 16)
 
   part_ = -1;
   if (auxv_cpu_type) {
-    if (strcmp(auxv_cpu_type, "power9") == 0) {
+    // use strncmp() in case "+" or "x" are added later.
+    if (strncmp(auxv_cpu_type, "power9", 6) == 0 ||
+        strncmp(auxv_cpu_type, "power1", 6) == 0) {     // e.g. "power10"
       part_ = PPC_POWER9;
-    } else if (strcmp(auxv_cpu_type, "power8") == 0) {
+    } else if (strncmp(auxv_cpu_type, "power8", 6) == 0) {
       part_ = PPC_POWER8;
-    } else if (strcmp(auxv_cpu_type, "power7") == 0) {
+    } else if (strncmp(auxv_cpu_type, "power7", 6) == 0) {  // or "power7+"
       part_ = PPC_POWER7;
-    } else if (strcmp(auxv_cpu_type, "power6") == 0) {
+    } else if (strncmp(auxv_cpu_type, "power6", 6) == 0) {  // or "power6x"
       part_ = PPC_POWER6;
+    // use exact strcmp() from here.
+    } else if (strcmp(auxv_cpu_type, "power5+") == 0) {     // adds FP rounding
+      part_ = PPC_POWER5_PLUS;
     } else if (strcmp(auxv_cpu_type, "power5") == 0) {
       part_ = PPC_POWER5;
-    } else if (strcmp(auxv_cpu_type, "ppc970") == 0) {
+    } else if (strcmp(auxv_cpu_type, "ppc970") == 0 ||
+               strcmp(auxv_cpu_type, "ppc-cell-be") == 0) {
       part_ = PPC_G5;
-    } else if (strcmp(auxv_cpu_type, "ppc7450") == 0) {
+    } else if (strcmp(auxv_cpu_type, "ppc7450") == 0 ||
+               strcmp(auxv_cpu_type, "ppc7400") == 0 ||
+               strcmp(auxv_cpu_type, "ppce6500") == 0) {
       part_ = PPC_G4;
     } else if (strcmp(auxv_cpu_type, "pa6t") == 0) {
       part_ = PPC_PA6T;
+    } else {
+      part_ = PPC_G3;
     }
   }
 
diff --git a/deps/v8/src/base/cpu.h b/deps/v8/src/base/cpu.h
index 8cec23c8..85d78285 100644
--- a/deps/v8/src/base/cpu.h
+++ b/deps/v8/src/base/cpu.h
@@ -66,10 +66,12 @@ class V8_BASE_EXPORT CPU final {
   // PPC-specific part codes
   enum {
     PPC_POWER5,
+    PPC_POWER5_PLUS,
     PPC_POWER6,
     PPC_POWER7,
     PPC_POWER8,
     PPC_POWER9,
+    PPC_G3,
     PPC_G4,
     PPC_G5,
     PPC_PA6T
diff --git a/deps/v8/src/codegen/cpu-features.h b/deps/v8/src/codegen/cpu-features.h
index eef98f77..73a8ed26 100644
--- a/deps/v8/src/codegen/cpu-features.h
+++ b/deps/v8/src/codegen/cpu-features.h
@@ -51,11 +51,12 @@ enum CpuFeature {
   MIPS_SIMD,  // MSA instructions
 
 #elif V8_TARGET_ARCH_PPC || V8_TARGET_ARCH_PPC64
-  FPU,
+  FP_ROUND_TO_INT,
   FPR_GPR_MOV,
   LWSYNC,
   ISELECT,
   VSX,
+  VMX,
   MODULO,
 
 #elif V8_TARGET_ARCH_S390X
diff --git a/deps/v8/src/codegen/ppc/assembler-ppc.cc b/deps/v8/src/codegen/ppc/assembler-ppc.cc
index 37a53b49..9ecff6a7 100644
--- a/deps/v8/src/codegen/ppc/assembler-ppc.cc
+++ b/deps/v8/src/codegen/ppc/assembler-ppc.cc
@@ -61,47 +61,52 @@ void CpuFeatures::ProbeImpl(bool cross_compile) {
   // Only use statically determined features for cross compile (snapshot).
   if (cross_compile) return;
 
-// Detect whether frim instruction is supported (POWER5+)
-// For now we will just check for processors we know do not
-// support it
 #ifndef USE_SIMULATOR
   // Probe for additional features at runtime.
   base::CPU cpu;
-  if (cpu.part() == base::CPU::PPC_POWER9) {
+  switch (cpu.part()) {
+  case base::CPU::PPC_POWER9:
     supported_ |= (1u << MODULO);
-  }
+    // fallthrough
+
+  case base::CPU::PPC_POWER8:
 #if V8_TARGET_ARCH_PPC64
-  if (cpu.part() == base::CPU::PPC_POWER8) {
     supported_ |= (1u << FPR_GPR_MOV);
-  }
 #endif
-  if (cpu.part() == base::CPU::PPC_POWER6 ||
-      cpu.part() == base::CPU::PPC_POWER7 ||
-      cpu.part() == base::CPU::PPC_POWER8) {
-    supported_ |= (1u << LWSYNC);
-  }
-  if (cpu.part() == base::CPU::PPC_POWER7 ||
-      cpu.part() == base::CPU::PPC_POWER8) {
+    // fallthrough
+
+  case base::CPU::PPC_POWER7:
     supported_ |= (1u << ISELECT);
     supported_ |= (1u << VSX);
+    // fallthrough
+
+  case base::CPU::PPC_POWER6:
+    supported_ |= (1u << LWSYNC);
+    supported_ |= (1u << VMX);
+    // fallthrough
+
+  case base::CPU::PPC_POWER5_PLUS:
+  case base::CPU::PPC_PA6T:
+    supported_ |= (1u << FP_ROUND_TO_INT);
+    break;
   }
-#if V8_OS_LINUX
-  if (!(cpu.part() == base::CPU::PPC_G5 || cpu.part() == base::CPU::PPC_G4)) {
-    // Assume support
-    supported_ |= (1u << FPU);
+  // Add VMX/AltiVec feature for the non-IBM CPUs that have it.
+  if (cpu.part() == base::CPU::PPC_PA6T ||
+      cpu.part() == base::CPU::PPC_G5 ||
+      cpu.part() == base::CPU::PPC_G4) {
+    supported_ |= (1u << VMX);
   }
+#if V8_OS_LINUX
   if (cpu.icache_line_size() != base::CPU::UNKNOWN_CACHE_LINE_SIZE) {
     icache_line_size_ = cpu.icache_line_size();
   }
-#elif V8_OS_AIX
-  // Assume support FP support and default cache line size
-  supported_ |= (1u << FPU);
 #endif
 #else  // Simulator
-  supported_ |= (1u << FPU);
+  supported_ |= (1u << FP_ROUND_TO_INT);
   supported_ |= (1u << LWSYNC);
   supported_ |= (1u << ISELECT);
   supported_ |= (1u << VSX);
+  supported_ |= (1u << VMX);
   supported_ |= (1u << MODULO);
 #if V8_TARGET_ARCH_PPC64
   supported_ |= (1u << FPR_GPR_MOV);
@@ -122,11 +127,12 @@ void CpuFeatures::PrintTarget() {
 }
 
 void CpuFeatures::PrintFeatures() {
-  printf("FPU=%d\n", CpuFeatures::IsSupported(FPU));
+  printf("FP_ROUND_TO_INT=%d\n", CpuFeatures::IsSupported(FP_ROUND_TO_INT));
   printf("FPR_GPR_MOV=%d\n", CpuFeatures::IsSupported(FPR_GPR_MOV));
   printf("LWSYNC=%d\n", CpuFeatures::IsSupported(LWSYNC));
   printf("ISELECT=%d\n", CpuFeatures::IsSupported(ISELECT));
   printf("VSX=%d\n", CpuFeatures::IsSupported(VSX));
+  printf("VMX=%d\n", CpuFeatures::IsSupported(VMX));
   printf("MODULO=%d\n", CpuFeatures::IsSupported(MODULO));
 }
 
@@ -1747,6 +1753,11 @@ void Assembler::fabs(const DoubleRegister frt, const DoubleRegister frb,
   emit(EXT4 | FABS | frt.code() * B21 | frb.code() * B11 | rc);
 }
 
+void Assembler::fnabs(const DoubleRegister frt, const DoubleRegister frb,
+                     RCBit rc) {
+  emit(EXT4 | FNABS | frt.code() * B21 | frb.code() * B11 | rc);
+}
+
 void Assembler::fmadd(const DoubleRegister frt, const DoubleRegister fra,
                       const DoubleRegister frc, const DoubleRegister frb,
                       RCBit rc) {
diff --git a/deps/v8/src/codegen/ppc/assembler-ppc.h b/deps/v8/src/codegen/ppc/assembler-ppc.h
index f26a3c89..f2cc8650 100644
--- a/deps/v8/src/codegen/ppc/assembler-ppc.h
+++ b/deps/v8/src/codegen/ppc/assembler-ppc.h
@@ -1008,6 +1008,8 @@ class Assembler : public AssemblerBase {
              RCBit rc = LeaveRC);
   void fabs(const DoubleRegister frt, const DoubleRegister frb,
             RCBit rc = LeaveRC);
+  void fnabs(const DoubleRegister frt, const DoubleRegister frb,
+            RCBit rc = LeaveRC);
   void fmadd(const DoubleRegister frt, const DoubleRegister fra,
              const DoubleRegister frc, const DoubleRegister frb,
              RCBit rc = LeaveRC);
diff --git a/deps/v8/src/common/globals.h b/deps/v8/src/common/globals.h
index dbc6b9af..5e127daf 100644
--- a/deps/v8/src/common/globals.h
+++ b/deps/v8/src/common/globals.h
@@ -203,7 +203,7 @@ constexpr bool kPlatformRequiresCodeRange = true;
 #if (V8_HOST_ARCH_PPC || V8_HOST_ARCH_PPC64) && \
     (V8_TARGET_ARCH_PPC || V8_TARGET_ARCH_PPC64) && V8_OS_LINUX
 constexpr size_t kMaximalCodeRangeSize = 512 * MB;
-constexpr size_t kMinExpectedOSPageSize = 64 * KB;  // OS page on PPC Linux
+constexpr size_t kMinExpectedOSPageSize = 4 * KB;  // min OS page size
 #elif V8_TARGET_ARCH_ARM64
 constexpr size_t kMaximalCodeRangeSize = 128 * MB;
 constexpr size_t kMinExpectedOSPageSize = 4 * KB;  // OS page.
@@ -226,7 +226,7 @@ constexpr intptr_t kIntptrSignBit = 0x80000000;
 constexpr bool kPlatformRequiresCodeRange = false;
 constexpr size_t kMaximalCodeRangeSize = 0 * MB;
 constexpr size_t kMinimumCodeRangeSize = 0 * MB;
-constexpr size_t kMinExpectedOSPageSize = 64 * KB;  // OS page on PPC Linux
+constexpr size_t kMinExpectedOSPageSize = 4 * KB;  // min OS page size
 #elif V8_TARGET_ARCH_MIPS
 constexpr bool kPlatformRequiresCodeRange = false;
 constexpr size_t kMaximalCodeRangeSize = 2048LL * MB;
diff --git a/deps/v8/src/compiler/backend/ppc/instruction-selector-ppc.cc b/deps/v8/src/compiler/backend/ppc/instruction-selector-ppc.cc
index 507542e2..5037e02f 100644
--- a/deps/v8/src/compiler/backend/ppc/instruction-selector-ppc.cc
+++ b/deps/v8/src/compiler/backend/ppc/instruction-selector-ppc.cc
@@ -2444,16 +2444,21 @@ void InstructionSelector::VisitLoadTransform(Node* node) { UNIMPLEMENTED(); }
 // static
 MachineOperatorBuilder::Flags
 InstructionSelector::SupportedMachineOperatorFlags() {
-  return MachineOperatorBuilder::kFloat32RoundDown |
-         MachineOperatorBuilder::kFloat64RoundDown |
-         MachineOperatorBuilder::kFloat32RoundUp |
-         MachineOperatorBuilder::kFloat64RoundUp |
-         MachineOperatorBuilder::kFloat32RoundTruncate |
-         MachineOperatorBuilder::kFloat64RoundTruncate |
-         MachineOperatorBuilder::kFloat64RoundTiesAway |
-         MachineOperatorBuilder::kWord32Popcnt |
-         MachineOperatorBuilder::kWord64Popcnt;
+  MachineOperatorBuilder::Flags flags = MachineOperatorBuilder::kWord32Popcnt;
+#if V8_TARGET_ARCH_PPC64
+  flags |= MachineOperatorBuilder::kWord64Popcnt;
+#endif
+  if (CpuFeatures::IsSupported(FP_ROUND_TO_INT)) {
+    flags |= MachineOperatorBuilder::kFloat32RoundDown |
+             MachineOperatorBuilder::kFloat64RoundDown |
+             MachineOperatorBuilder::kFloat32RoundUp |
+             MachineOperatorBuilder::kFloat64RoundUp |
+             MachineOperatorBuilder::kFloat32RoundTruncate |
+             MachineOperatorBuilder::kFloat64RoundTruncate |
+             MachineOperatorBuilder::kFloat64RoundTiesAway;
+  }
   // We omit kWord32ShiftIsSafe as s[rl]w use 0x3F as a mask rather than 0x1F.
+  return flags;
 }
 
 // static
diff --git a/deps/v8/src/heap/base/asm/ppc/push_registers_asm.cc b/deps/v8/src/heap/base/asm/ppc/push_registers_asm.cc
index 6936819b..2aa1b7ed 100644
--- a/deps/v8/src/heap/base/asm/ppc/push_registers_asm.cc
+++ b/deps/v8/src/heap/base/asm/ppc/push_registers_asm.cc
@@ -33,7 +33,7 @@ asm(
     // At anytime, SP (r1) needs to be multiple of 16 (i.e. 16-aligned).
     "  mflr 0                                          \n"
     "  std 0, 16(1)                                    \n"
-#if defined(_AIX)
+#if ABI_USES_FUNCTION_DESCRIPTORS
     "  std 2, 40(1)                                    \n"
 #else
     "  std 2, 24(1)                                    \n"
@@ -61,10 +61,10 @@ asm(
     // Pass 2nd parameter (r4) unchanged (StackVisitor*).
     // Save 3rd parameter (r5; IterateStackCallback).
     "  mr 6, 5                                         \n"
-#if defined(_AIX)
+#if ABI_USES_FUNCTION_DESCRIPTORS
     // Set up TOC for callee.
     "  ld 2,8(5)                                       \n"
-    // AIX uses function decorators, which means that
+    // AIX/PPC64BE (ELFv1) uses function descriptors, which means that
     // pointers to functions do not point to code, but
     //  instead point to metadata about them, hence
     // need to deterrence.
@@ -72,7 +72,7 @@ asm(
 #endif
     // Pass 3rd parameter as sp (stack pointer).
     "  mr 5, 1                                         \n"
-#if !defined(_AIX)
+#if !ABI_USES_FUNCTION_DESCRIPTORS
     // Set up r12 to be equal to the callee address (in order for TOC
     // relocation). Only needed on LE Linux.
     "  mr 12, 6                                        \n"
@@ -85,7 +85,7 @@ asm(
     // Restore lr.
     "  ld 0, 16(1)                                     \n"
     "  mtlr  0                                         \n"
-#if defined(_AIX)
+#if ABI_USES_FUNCTION_DESCRIPTORS
     // Restore TOC pointer.
     "  ld 2, 40(1)                                     \n"
 #else