AArch64: add support for llvm.aarch64.hint intrinsic

This adds a llvm.aarch64.hint intrinsic to mirror the llvm.arm.hint in order to
support the various hint intrinsic functions in the ACLE.

Add an optional pattern field that permits the subclass to specify the pattern
that matches the selection.  The intrinsic pattern is set as mayLoad, mayStore,
so overload the value for the definition of the hint instruction.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212883 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/IR/IntrinsicsAArch64.td b/include/llvm/IR/IntrinsicsAArch64.td
index e3c0fb359901d21b90d439f4722ff820a308b8c9..050762b61145cacf80c34bea0a1fffd77e476124 100644 (file)
--- a/include/llvm/IR/IntrinsicsAArch64.td
+++ b/include/llvm/IR/IntrinsicsAArch64.td
@@ -32,6 +32,11 @@ def int_aarch64_sdiv : Intrinsic<[llvm_anyint_ty], [LLVMMatchType<0>,
 def int_aarch64_udiv : Intrinsic<[llvm_anyint_ty], [LLVMMatchType<0>,
                                 LLVMMatchType<0>], [IntrNoMem]>;
 
+//===----------------------------------------------------------------------===//
+// HINT
+
+def int_aarch64_hint : Intrinsic<[], [llvm_i32_ty]>;
+
 //===----------------------------------------------------------------------===//
 // RBIT
 

diff --git a/lib/Target/AArch64/AArch64InstrFormats.td b/lib/Target/AArch64/AArch64InstrFormats.td
index 5007172f15399be42ccbb3f1fe749f455d34cad3..0c9687eca5625774813de79df1e47f812ac93ae6 100644 (file)
--- a/lib/Target/AArch64/AArch64InstrFormats.td
+++ b/lib/Target/AArch64/AArch64InstrFormats.td
@@ -776,15 +776,17 @@ def simdimmtype10 : Operand<i32>,
 
 // Base encoding for system instruction operands.
 let mayLoad = 0, mayStore = 0, hasSideEffects = 1 in
-class BaseSystemI<bit L, dag oops, dag iops, string asm, string operands>
-    : I<oops, iops, asm, operands, "", []> {
+class BaseSystemI<bit L, dag oops, dag iops, string asm, string operands,
+                  list<dag> pattern = []>
+    : I<oops, iops, asm, operands, "", pattern> {
   let Inst{31-22} = 0b1101010100;
   let Inst{21}    = L;
 }
 
 // System instructions which do not have an Rt register.
-class SimpleSystemI<bit L, dag iops, string asm, string operands>
-    : BaseSystemI<L, (outs), iops, asm, operands> {
+class SimpleSystemI<bit L, dag iops, string asm, string operands,
+                    list<dag> pattern = []>
+    : BaseSystemI<L, (outs), iops, asm, operands, pattern> {
   let Inst{4-0} = 0b11111;
 }
 
@@ -797,13 +799,17 @@ class RtSystemI<bit L, dag oops, dag iops, string asm, string operands>
 }
 
 // Hint instructions that take both a CRm and a 3-bit immediate.
-class HintI<string mnemonic>
-    : SimpleSystemI<0, (ins imm0_127:$imm), mnemonic#" $imm", "">,
-      Sched<[WriteHint]> {
-  bits <7> imm;
-  let Inst{20-12} = 0b000110010;
-  let Inst{11-5} = imm;
-}
+// NOTE: ideally, this would have mayStore = 0, mayLoad = 0, but we cannot
+// model patterns with sufficiently fine granularity
+let mayStore = 1, mayLoad = 1, hasSideEffects = 1 in
+  class HintI<string mnemonic>
+      : SimpleSystemI<0, (ins imm0_127:$imm), mnemonic#" $imm", "",
+                      [(int_aarch64_hint imm0_127:$imm)]>,
+        Sched<[WriteHint]> {
+    bits <7> imm;
+    let Inst{20-12} = 0b000110010;
+    let Inst{11-5} = imm;
+  }
 
 // System instructions taking a single literal operand which encodes into
 // CRm. op2 differentiates the opcodes.

diff --git a/test/CodeGen/AArch64/hints.ll b/test/CodeGen/AArch64/hints.ll
new file mode 100644 (file)
index 0000000..d7d9e23
--- /dev/null
+++ b/test/CodeGen/AArch64/hints.ll
@@ -0,0 +1,67 @@
+; RUN: llc -mtriple aarch64-eabi -o - %s | FileCheck %s
+
+declare void @llvm.aarch64.hint(i32) nounwind
+
+define void @hint_nop() {
+entry:
+  tail call void @llvm.aarch64.hint(i32 0) nounwind
+  ret void
+}
+
+; CHECK-LABEL: hint_nop
+; CHECK: nop
+
+define void @hint_yield() {
+entry:
+  tail call void @llvm.aarch64.hint(i32 1) nounwind
+  ret void
+}
+
+; CHECK-LABEL: hint_yield
+; CHECK: yield
+
+define void @hint_wfe() {
+entry:
+  tail call void @llvm.aarch64.hint(i32 2) nounwind
+  ret void
+}
+
+; CHECK-LABEL: hint_wfe
+; CHECK: wfe
+
+define void @hint_wfi() {
+entry:
+  tail call void @llvm.aarch64.hint(i32 3) nounwind
+  ret void
+}
+
+; CHECK-LABEL: hint_wfi
+; CHECK: wfi
+
+define void @hint_sev() {
+entry:
+  tail call void @llvm.aarch64.hint(i32 4) nounwind
+  ret void
+}
+
+; CHECK-LABEL: hint_sev
+; CHECK: sev
+
+define void @hint_sevl() {
+entry:
+  tail call void @llvm.aarch64.hint(i32 5) nounwind
+  ret void
+}
+
+; CHECK-LABEL: hint_sevl
+; CHECK: sevl
+
+define void @hint_undefined() {
+entry:
+  tail call void @llvm.aarch64.hint(i32 8) nounwind
+  ret void
+}
+
+; CHECK-LABEL: hint_undefined
+; CHECK: hint #0x8
+