[MIPS] Add cpu octeon and some instructions

The Octeon cpu from Cavium Networks is mips64r2 based and has an extended
instruction set. In order to utilize this with LLVM, a new cpu feature "octeon"
and a subtarget feature "cnmips" is added. A small set of new instructions
(baddu, dmul, pop, dpop, seq, sne) is also added. LLVM generates dmul, pop and
dpop instructions with option -mcpu=octeon or -mattr=+cnmips.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204337 91177308-0d34-0410-b5e6-96231b3b80d8

test/CodeGen/Mips/octeon.ll

@@ -0,0 +1,15 @@
+; RUN: llc -O1 < %s -march=mips64 -mcpu=octeon | FileCheck %s -check-prefix=OCTEON
+; RUN: llc -O1 < %s -march=mips64 -mcpu=mips64 | FileCheck %s -check-prefix=MIPS64
+
+define i64 @mul(i64 %a, i64 %b) nounwind {
+entry:
+; OCTEON-LABEL: mul:
+; OCTEON: jr    $ra
+; OCTEON: dmul  $2, $4, $5
+; MIPS64-LABEL: mul:
+; MIPS64: dmult
+; MIPS64: jr
+; MIPS64: mflo
+  %res = mul i64 %a, %b
+  ret i64 %res
+}

test/CodeGen/Mips/octeon_popcnt.ll

@@ -0,0 +1,47 @@
+; RUN: llc -O1 -march=mips64 -mcpu=octeon < %s | FileCheck %s -check-prefix=OCTEON
+; RUN: llc -O1 -march=mips64 -mcpu=mips64 < %s | FileCheck %s -check-prefix=MIPS64
+
+define i8 @cnt8(i8 %x) nounwind readnone {
+  %cnt = tail call i8 @llvm.ctpop.i8(i8 %x)
+  ret i8 %cnt
+; OCTEON-LABEL: cnt8:
+; OCTEON: jr   $ra
+; OCTEON: pop  $2, $1
+; MIPS64-LABEL: cnt8:
+; MIPS64-NOT: pop
+}
+
+define i16 @cnt16(i16 %x) nounwind readnone {
+  %cnt = tail call i16 @llvm.ctpop.i16(i16 %x)
+  ret i16 %cnt
+; OCTEON-LABEL: cnt16:
+; OCTEON: jr   $ra
+; OCTEON: pop  $2, $1
+; MIPS64-LABEL: cnt16:
+; MIPS64-NOT: pop
+}
+
+define i32 @cnt32(i32 %x) nounwind readnone {
+  %cnt = tail call i32 @llvm.ctpop.i32(i32 %x)
+  ret i32 %cnt
+; OCTEON-LABEL: cnt32:
+; OCTEON: jr   $ra
+; OCTEON: pop  $2, $4
+; MIPS64-LABEL: cnt32:
+; MIPS64-NOT: pop
+}
+
+define i64 @cnt64(i64 %x) nounwind readnone {
+  %cnt = tail call i64 @llvm.ctpop.i64(i64 %x)
+  ret i64 %cnt
+; OCTEON-LABEL: cnt64:
+; OCTEON: jr   $ra
+; OCTEON: dpop $2, $4
+; MIPS64-LABEL: cnt64:
+; MIPS64-NOT: dpop
+}
+
+declare i8 @llvm.ctpop.i8(i8) nounwind readnone
+declare i16 @llvm.ctpop.i16(i16) nounwind readnone
+declare i32 @llvm.ctpop.i32(i32) nounwind readnone
+declare i64 @llvm.ctpop.i64(i64) nounwind readnone