1 files changed, 31 insertions, 4 deletions

diff --git a/libartbase/arch/instruction_set.h b/libartbase/arch/instruction_set.h
index e68ff08c17..8d59f1b1e4 100644
--- a/libartbase/arch/instruction_set.h
+++ b/libartbase/arch/instruction_set.h
@@ -31,6 +31,7 @@ enum class InstructionSet {
   kArm,
   kArm64,
   kThumb2,
+  kRiscv64,
   kX86,
   kX86_64,
   kLast = kX86_64
@@ -41,6 +42,8 @@ std::ostream& operator<<(std::ostream& os, InstructionSet rhs);
 static constexpr InstructionSet kRuntimeISA = InstructionSet::kArm;
 #elif defined(__aarch64__)
 static constexpr InstructionSet kRuntimeISA = InstructionSet::kArm64;
+#elif defined (__riscv)
+static constexpr InstructionSet kRuntimeISA = InstructionSet::kRiscv64;
 #elif defined(__i386__)
 static constexpr InstructionSet kRuntimeISA = InstructionSet::kX86;
 #elif defined(__x86_64__)
@@ -52,6 +55,7 @@ static constexpr InstructionSet kRuntimeISA = InstructionSet::kNone;
 // Architecture-specific pointer sizes
 static constexpr PointerSize kArmPointerSize = PointerSize::k32;
 static constexpr PointerSize kArm64PointerSize = PointerSize::k64;
+static constexpr PointerSize kRiscv64PointerSize = PointerSize::k64;
 static constexpr PointerSize kX86PointerSize = PointerSize::k32;
 static constexpr PointerSize kX86_64PointerSize = PointerSize::k64;
 
@@ -63,12 +67,17 @@ static constexpr size_t kArm64DefaultSVEVectorLength = 256;
 // ARM processors require code to be 4-byte aligned, but ARM ELF requires 8.
 static constexpr size_t kArmCodeAlignment = 8;
 static constexpr size_t kArm64CodeAlignment = 16;
+static constexpr size_t kRiscv64CodeAlignment = 16;
 static constexpr size_t kX86CodeAlignment = 16;
 
 // Instruction alignment (every instruction must be aligned at this boundary). This differs from
 // code alignment, which applies only to the first instruction of a subroutine.
+// Android requires the RISC-V compressed instruction extension, and that allows
+// *all* instructions (not just compressed ones) to be 2-byte aligned rather
+// than the usual 4-byte alignment requirement.
 static constexpr size_t kThumb2InstructionAlignment = 2;
 static constexpr size_t kArm64InstructionAlignment = 4;
+static constexpr size_t kRiscv64InstructionAlignment = 2;
 static constexpr size_t kX86InstructionAlignment = 1;
 static constexpr size_t kX86_64InstructionAlignment = 1;
 
@@ -88,6 +97,8 @@ constexpr PointerSize GetInstructionSetPointerSize(InstructionSet isa) {
       return kArmPointerSize;
     case InstructionSet::kArm64:
       return kArm64PointerSize;
+    case InstructionSet::kRiscv64:
+      return kRiscv64PointerSize;
     case InstructionSet::kX86:
       return kX86PointerSize;
     case InstructionSet::kX86_64:
@@ -104,6 +115,7 @@ constexpr bool IsValidInstructionSet(InstructionSet isa) {
     case InstructionSet::kArm:
     case InstructionSet::kThumb2:
     case InstructionSet::kArm64:
+    case InstructionSet::kRiscv64:
     case InstructionSet::kX86:
     case InstructionSet::kX86_64:
       return true;
@@ -122,6 +134,8 @@ constexpr size_t GetInstructionSetInstructionAlignment(InstructionSet isa) {
       return kThumb2InstructionAlignment;
     case InstructionSet::kArm64:
       return kArm64InstructionAlignment;
+    case InstructionSet::kRiscv64:
+      return kRiscv64InstructionAlignment;
     case InstructionSet::kX86:
       return kX86InstructionAlignment;
     case InstructionSet::kX86_64:
@@ -141,6 +155,8 @@ constexpr size_t GetInstructionSetCodeAlignment(InstructionSet isa) {
       return kArmCodeAlignment;
     case InstructionSet::kArm64:
       return kArm64CodeAlignment;
+    case InstructionSet::kRiscv64:
+      return kRiscv64CodeAlignment;
     case InstructionSet::kX86:
       // Fall-through.
     case InstructionSet::kX86_64:
@@ -158,6 +174,7 @@ constexpr size_t GetInstructionSetEntryPointAdjustment(InstructionSet isa) {
   switch (isa) {
     case InstructionSet::kArm:
     case InstructionSet::kArm64:
+    case InstructionSet::kRiscv64:
     case InstructionSet::kX86:
     case InstructionSet::kX86_64:
       return 0;
@@ -180,6 +197,7 @@ constexpr bool Is64BitInstructionSet(InstructionSet isa) {
       return false;
 
     case InstructionSet::kArm64:
+    case InstructionSet::kRiscv64:
     case InstructionSet::kX86_64:
       return true;
 
@@ -201,6 +219,8 @@ constexpr size_t GetBytesPerGprSpillLocation(InstructionSet isa) {
       return 4;
     case InstructionSet::kArm64:
       return 8;
+    case InstructionSet::kRiscv64:
+      return 8;
     case InstructionSet::kX86:
       return 4;
     case InstructionSet::kX86_64:
@@ -220,6 +240,8 @@ constexpr size_t GetBytesPerFprSpillLocation(InstructionSet isa) {
       return 4;
     case InstructionSet::kArm64:
       return 8;
+    case InstructionSet::kRiscv64:
+      return 8;
     case InstructionSet::kX86:
       return 8;
     case InstructionSet::kX86_64:
@@ -237,14 +259,16 @@ std::vector<InstructionSet> GetSupportedInstructionSets(std::string* error_msg);
 namespace instruction_set_details {
 
 #if !defined(ART_STACK_OVERFLOW_GAP_arm) || !defined(ART_STACK_OVERFLOW_GAP_arm64) || \
+    !defined(ART_STACK_OVERFLOW_GAP_riscv64) || \
     !defined(ART_STACK_OVERFLOW_GAP_x86) || !defined(ART_STACK_OVERFLOW_GAP_x86_64)
 #error "Missing defines for stack overflow gap"
 #endif
 
-static constexpr size_t kArmStackOverflowReservedBytes    = ART_STACK_OVERFLOW_GAP_arm;
-static constexpr size_t kArm64StackOverflowReservedBytes  = ART_STACK_OVERFLOW_GAP_arm64;
-static constexpr size_t kX86StackOverflowReservedBytes    = ART_STACK_OVERFLOW_GAP_x86;
-static constexpr size_t kX86_64StackOverflowReservedBytes = ART_STACK_OVERFLOW_GAP_x86_64;
+static constexpr size_t kArmStackOverflowReservedBytes     = ART_STACK_OVERFLOW_GAP_arm;
+static constexpr size_t kArm64StackOverflowReservedBytes   = ART_STACK_OVERFLOW_GAP_arm64;
+static constexpr size_t kRiscv64StackOverflowReservedBytes = ART_STACK_OVERFLOW_GAP_riscv64;
+static constexpr size_t kX86StackOverflowReservedBytes     = ART_STACK_OVERFLOW_GAP_x86;
+static constexpr size_t kX86_64StackOverflowReservedBytes  = ART_STACK_OVERFLOW_GAP_x86_64;
 
 NO_RETURN void GetStackOverflowReservedBytesFailure(const char* error_msg);
 
@@ -260,6 +284,9 @@ constexpr size_t GetStackOverflowReservedBytes(InstructionSet isa) {
     case InstructionSet::kArm64:
       return instruction_set_details::kArm64StackOverflowReservedBytes;
 
+    case InstructionSet::kRiscv64:
+      return instruction_set_details::kRiscv64StackOverflowReservedBytes;
+
     case InstructionSet::kX86:
       return instruction_set_details::kX86StackOverflowReservedBytes;