[SystemZ] Introduce distinction between the jg/jl family of mnemonics for GNU as vs HLASM

- This patch adds in the distinction between jg[*] and jl[*] pc-relative
  mnemonics based on the variant/dialect.
- Under the hlasm variant, we use the jl[*] family of mnemonics and under
  the att (GNU as) variant, we use the jg[*] family of mnemonics.
- jgnop which was added in https://reviews.llvm.org/D92185, is now restricted
  to att variant. jlnop is introduced and restricted to hlasm variant.
- The br[*]l additional mnemonics are mapped to either jl[*]/jg[*] based on
  the variant.

Reviewed By: uweigand

Differential Revision: https://reviews.llvm.org/D97581

Author: Anirudh Prasad

llvm/lib/Target/SystemZ/SystemZInstrFormats.td

@@ -1921,9 +1921,13 @@ class ICV<string name>
 
 // Defines a class that makes it easier to define
 // a MnemonicAlias when CondVariant's are involved.
-class MnemonicCondBranchAlias<CondVariant V, string from, string to>
-  : MnemonicAlias<!subst("#", V.suffix, from), !subst("#", V.suffix, to),
-                  V.asmvariant>;
+multiclass MnemonicCondBranchAlias<CondVariant V, string from, string to,
+                                   string asmvariant = V.asmvariant> {
+  if !or(!eq(V.asmvariant, ""), !eq(V.asmvariant, asmvariant)) then
+    def "" : MnemonicAlias<!subst("#", V.suffix, from),
+                           !subst("#", V.suffix, to),
+                           asmvariant>;
+}
 
 //===----------------------------------------------------------------------===//
 // Instruction definitions with semantics

llvm/lib/Target/SystemZ/SystemZInstrInfo.td

@@ -81,7 +81,7 @@ let isBranch = 1, isTerminator = 1, Uses = [CC] in {
   foreach V = [ "E", "NE", "H", "NH", "L", "NL", "HE", "NHE", "LE", "NLE",
                 "Z", "NZ", "P", "NP", "M", "NM", "LH", "NLH", "O", "NO" ] in {
     def JAsm#V  : FixedCondBranchRI <CV<V>, "j#",  0xA74>;
-    def JGAsm#V : FixedCondBranchRIL<CV<V>, "jg#", 0xC04>;
+    def JGAsm#V : FixedCondBranchRIL<CV<V>, "j{g|l}#", 0xC04>;
     let isIndirectBranch = 1 in {
       def BAsm#V  : FixedCondBranchRX <CV<V>, "b#",  0x47>;
       def BRAsm#V : FixedCondBranchRR <CV<V>, "b#r", 0x07>;
@@ -95,7 +95,7 @@ let isBranch = 1, isTerminator = 1, Uses = [CC] in {
 // conditional branches with the condition mask set to "always".
 let isBranch = 1, isTerminator = 1, isBarrier = 1 in {
   def J  : FixedCondBranchRI <CondAlways, "j",  0xA74, br>;
-  def JG : FixedCondBranchRIL<CondAlways, "jg", 0xC04>;
+  def JG : FixedCondBranchRIL<CondAlways, "j{g|lu}", 0xC04>;
   let isIndirectBranch = 1 in {
     def B  : FixedCondBranchRX<CondAlways, "b",  0x47>;
     def BR : FixedCondBranchRR<CondAlways, "br", 0x07, brind>;
@@ -117,7 +117,8 @@ def NOPR_bare : InstAlias<"nopr", (BCRAsm 0, R0D), 0>;
 def JNOP : InstAlias<"jnop\t$RI2", (BRCAsm 0, brtarget16:$RI2), 0>;
 
 // An alias of BRCL 0, label
-def JGNOP : InstAlias<"jgnop\t$RI2", (BRCLAsm 0, brtarget32:$RI2), 0>;
+// jgnop on att ; jlnop on hlasm
+def JGNOP : InstAlias<"{jgnop|jlnop}\t$RI2", (BRCLAsm 0, brtarget32:$RI2), 0>;
 
 // Fused compare-and-branch instructions.
 //
@@ -2375,10 +2376,12 @@ def JXHG  : MnemonicAlias<"jxhg", "brxhg">;
 def JXLEG : MnemonicAlias<"jxleg", "brxlg">;
 
 def BRU   : MnemonicAlias<"bru", "j">;
-def BRUL  : MnemonicAlias<"brul", "jg">;
+def BRUL  : MnemonicAlias<"brul", "jg", "att">;
+def BRUL_HLASM  : MnemonicAlias<"brul", "jlu", "hlasm">;
 
 foreach V = [ "E", "NE", "H", "NH", "L", "NL", "HE", "NHE", "LE", "NLE",
               "Z", "NZ", "P", "NP", "M", "NM", "LH", "NLH", "O", "NO" ] in {
-  def BRUAsm#V : MnemonicCondBranchAlias <CV<V>, "br#", "j#">;
-  def BRULAsm#V : MnemonicCondBranchAlias <CV<V>, "br#l", "jg#">;
+  defm BRUAsm#V  : MnemonicCondBranchAlias <CV<V>, "br#", "j#">;
+  defm BRULAsm#V : MnemonicCondBranchAlias <CV<V>, "br#l", "jg#", "att">;
+  defm BRUL_HLASMAsm#V : MnemonicCondBranchAlias <CV<V>, "br#l", "jl#", "hlasm">;
 }

llvm/test/MC/SystemZ/insn-bad.s

@@ -561,6 +561,65 @@
 	jnop	1
 	jnop	0x10000
 
+#CHECK: error: invalid instruction
+#CHECK: jlu     label
+#CHECK: error: invalid instruction
+#CHECK: jlne    label
+#CHECK: error: invalid instruction
+#CHECK: jlnh    label
+#CHECK: error: invalid instruction
+#CHECK: jll     label
+#CHECK: error: invalid instruction
+#CHECK: jlnl    label
+#CHECK: error: invalid instruction
+#CHECK: jlhe    label
+#CHECK: error: invalid instruction
+#CHECK: jlnhe   label
+#CHECK: error: invalid instruction
+#CHECK: jlle    label
+#CHECK: error: invalid instruction
+#CHECK: jlnle   label
+#CHECK: error: invalid instruction
+#CHECK: jlz     label
+#CHECK: error: invalid instruction
+#CHECK: jlnz    label
+#CHECK: error: invalid instruction
+#CHECK: jlp     label
+#CHECK: error: invalid instruction
+#CHECK: jlnp    label
+#CHECK: error: invalid instruction
+#CHECK: jlm     label
+#CHECK: error: invalid instruction
+#CHECK: jlnm    label
+#CHECK: error: invalid instruction
+#CHECK: jllh    label
+#CHECK: error: invalid instruction
+#CHECK: jllnlh  label
+#CHECK: error: invalid instruction
+#CHECK: jlo     label
+#CHECK: error: invalid instruction
+#CHECK: jlno    label
+
+	jlu	label
+	jlne	label
+	jlnh	label
+	jll	label
+	jlnl	label
+	jlhe	label
+	jlnhe	label
+	jlle	label
+	jlnle	label
+	jlz	label
+	jlnz	label
+	jlp	label
+	jlnp	label
+	jlm	label
+	jlnm	label
+	jllh	label
+	jllnlh	label
+	jlo	label
+	jlno	label
+
 #CHECK: error: invalid operand
 #CHECK: brc	foo, bar
 #CHECK: error: invalid operand
@@ -598,6 +657,11 @@
 	jgnop	1
 	jgnop	0x100000000
 
+
+#CHECK: error: invalid instruction
+#CHECK: jlnop	label
+	jlnop	label
+
 #CHECK: error: invalid operand
 #CHECK: brcl	foo, bar
 #CHECK: error: invalid operand