[PATCH 4/7] riscv: thead: Add support for XTheadCondMov ISA extensions

[Christoph Muellner <christoph.muellner@vrull.eu>]

From: Christoph Müllner <christoph.muellner@vrull.eu>

This patch adds support for XTheadCondMov ISA extension.
The extension brings a one-sided conditional move (no else-assignment).
Given that GCC has a great if-conversion pass, we don't need to do much,
besides properly expanding mov<mode>cc accordingly and adjust the cost
model.

gcc/ChangeLog:

	* config/riscv/iterators.md (TARGET_64BIT): Add GPR2 iterator.
	* config/riscv/riscv.cc (riscv_rtx_costs): Add costs for
	  XTheadCondMov.
	(riscv_expand_conditional_move_onesided): New function.
	(riscv_expand_conditional_move): New function.
	* config/riscv/riscv.md: Add support for XTheadCondMov.
	* config/riscv/thead.md (*th_cond_mov<GPR:mode><GPR2:mode>): Add
	  support for XTheadCondMov.
	(*th_cond_gpr_mov<GPR:mode><GPR2:mode>): Likewise.

gcc/testsuite/ChangeLog:

	* gcc.target/riscv/xtheadcondmov-mveqz-imm-eqz.c: New test.
	* gcc.target/riscv/xtheadcondmov-mveqz-imm-not.c: New test.
	* gcc.target/riscv/xtheadcondmov-mveqz-reg-eqz.c: New test.
	* gcc.target/riscv/xtheadcondmov-mveqz-reg-not.c: New test.
	* gcc.target/riscv/xtheadcondmov-mvnez-imm-cond.c: New test.
	* gcc.target/riscv/xtheadcondmov-mvnez-imm-nez.c: New test.
	* gcc.target/riscv/xtheadcondmov-mvnez-reg-cond.c: New test.
	* gcc.target/riscv/xtheadcondmov-mvnez-reg-nez.c: New test.

Signed-off-by: Christoph Müllner <christoph.muellner@vrull.eu>
---
 gcc/config/riscv/iterators.md                 |  4 ++
 gcc/config/riscv/riscv.cc                     | 53 ++++++++++++++++---
 gcc/config/riscv/riscv.md                     |  7 +--
 gcc/config/riscv/thead.md                     | 35 ++++++++++++
 .../riscv/xtheadcondmov-mveqz-imm-eqz.c       | 37 +++++++++++++
 .../riscv/xtheadcondmov-mveqz-imm-not.c       | 37 +++++++++++++
 .../riscv/xtheadcondmov-mveqz-reg-eqz.c       | 37 +++++++++++++
 .../riscv/xtheadcondmov-mveqz-reg-not.c       | 37 +++++++++++++
 .../riscv/xtheadcondmov-mvnez-imm-cond.c      | 37 +++++++++++++
 .../riscv/xtheadcondmov-mvnez-imm-nez.c       | 37 +++++++++++++
 .../riscv/xtheadcondmov-mvnez-reg-cond.c      | 37 +++++++++++++
 .../riscv/xtheadcondmov-mvnez-reg-nez.c       | 37 +++++++++++++
 12 files changed, 386 insertions(+), 9 deletions(-)
 create mode 100644 gcc/testsuite/gcc.target/riscv/xtheadcondmov-mveqz-imm-eqz.c
 create mode 100644 gcc/testsuite/gcc.target/riscv/xtheadcondmov-mveqz-imm-not.c
 create mode 100644 gcc/testsuite/gcc.target/riscv/xtheadcondmov-mveqz-reg-eqz.c
 create mode 100644 gcc/testsuite/gcc.target/riscv/xtheadcondmov-mveqz-reg-not.c
 create mode 100644 gcc/testsuite/gcc.target/riscv/xtheadcondmov-mvnez-imm-cond.c
 create mode 100644 gcc/testsuite/gcc.target/riscv/xtheadcondmov-mvnez-imm-nez.c
 create mode 100644 gcc/testsuite/gcc.target/riscv/xtheadcondmov-mvnez-reg-cond.c
 create mode 100644 gcc/testsuite/gcc.target/riscv/xtheadcondmov-mvnez-reg-nez.c

diff --git a/gcc/config/riscv/iterators.md b/gcc/config/riscv/iterators.md
index 50380ecfac9..3932eab14fa 100644
--- a/gcc/config/riscv/iterators.md
+++ b/gcc/config/riscv/iterators.md
@@ -26,6 +26,10 @@
 ;; from the same template.
 (define_mode_iterator GPR [SI (DI "TARGET_64BIT")])
 
+;; A copy of GPR that can be used when a pattern has two independent
+;; modes.
+(define_mode_iterator GPR2 [SI (DI "TARGET_64BIT")])
+
 ;; This mode iterator allows :P to be used for patterns that operate on
 ;; pointer-sized quantities.  Exactly one of the two alternatives will match.
 (define_mode_iterator P [(SI "Pmode == SImode") (DI "Pmode == DImode")])
diff --git a/gcc/config/riscv/riscv.cc b/gcc/config/riscv/riscv.cc
index decade0fedd..9a795264e00 100644
--- a/gcc/config/riscv/riscv.cc
+++ b/gcc/config/riscv/riscv.cc
@@ -2269,8 +2269,8 @@ riscv_rtx_costs (rtx x, machine_mode mode, int outer_code, int opno ATTRIBUTE_UN
       return false;
 
     case IF_THEN_ELSE:
-      if (TARGET_SFB_ALU
-	  && register_operand (XEXP (x, 1), mode)
+      if ((TARGET_SFB_ALU || TARGET_XTHEADCONDMOV)
+	  && reg_or_0_operand (XEXP (x, 1), mode)
 	  && sfb_alu_operand (XEXP (x, 2), mode)
 	  && comparison_operator (XEXP (x, 0), VOIDmode))
 	{
@@ -3231,16 +3231,57 @@ riscv_expand_conditional_branch (rtx label, rtx_code code, rtx op0, rtx op1)
   emit_jump_insn (gen_condjump (condition, label));
 }
 
+/* Helper to emit two one-sided conditional moves for the movecc.  */
+
+static void
+riscv_expand_conditional_move_onesided (rtx dest, rtx cons, rtx alt,
+					rtx_code code, rtx op0, rtx op1)
+{
+  machine_mode mode = GET_MODE (dest);
+
+  gcc_assert (GET_MODE_CLASS (mode) == MODE_INT);
+  gcc_assert (reg_or_0_operand (cons, mode));
+  gcc_assert (reg_or_0_operand (alt, mode));
+
+  riscv_emit_int_compare (&code, &op0, &op1);
+  rtx cond = gen_rtx_fmt_ee (code, GET_MODE (op0), op0, op1);
+
+  rtx tmp1 = gen_reg_rtx (mode);
+  rtx tmp2 = gen_reg_rtx (mode);
+
+  emit_insn (gen_rtx_SET (tmp1, gen_rtx_IF_THEN_ELSE (mode, cond,
+						      cons, const0_rtx)));
+
+  /* We need to expand a sequence for both blocks and we do that such,
+     that the second conditional move will use the inverted condition.
+     We use temporaries that are or'd to the dest register.  */
+  cond = gen_rtx_fmt_ee ((code == EQ) ? NE : EQ, GET_MODE (op0), op0, op1);
+  emit_insn (gen_rtx_SET (tmp2, gen_rtx_IF_THEN_ELSE (mode, cond,
+						      alt, const0_rtx)));
+
+  emit_insn (gen_rtx_SET (dest, gen_rtx_IOR (mode, tmp1, tmp2)));
+ }
+
 /* If (CODE OP0 OP1) holds, move CONS to DEST; else move ALT to DEST.  */
 
 void
 riscv_expand_conditional_move (rtx dest, rtx cons, rtx alt, rtx_code code,
 			       rtx op0, rtx op1)
 {
-  riscv_emit_int_compare (&code, &op0, &op1);
-  rtx cond = gen_rtx_fmt_ee (code, GET_MODE (op0), op0, op1);
-  emit_insn (gen_rtx_SET (dest, gen_rtx_IF_THEN_ELSE (GET_MODE (dest), cond,
-						      cons, alt)));
+  machine_mode mode = GET_MODE (dest);
+
+  if (TARGET_XTHEADCONDMOV
+      && GET_MODE_CLASS (mode) == MODE_INT
+      && reg_or_0_operand (cons, mode)
+      && reg_or_0_operand (alt, mode))
+    riscv_expand_conditional_move_onesided (dest, cons, alt, code, op0, op1);
+  else
+    {
+      riscv_emit_int_compare (&code, &op0, &op1);
+      rtx cond = gen_rtx_fmt_ee (code, GET_MODE (op0), op0, op1);
+      emit_insn (gen_rtx_SET (dest, gen_rtx_IF_THEN_ELSE (GET_MODE (dest),
+							  cond, cons, alt)));
+    }
 }
 
 /* Implement TARGET_FUNCTION_ARG_BOUNDARY.  Every parameter gets at
diff --git a/gcc/config/riscv/riscv.md b/gcc/config/riscv/riscv.md
index a9254df7820..850a2d958e4 100644
--- a/gcc/config/riscv/riscv.md
+++ b/gcc/config/riscv/riscv.md
@@ -233,6 +233,7 @@ (define_attr "enabled" "no,yes"
 ;; nop		no operation
 ;; ghost	an instruction that produces no real code
 ;; bitmanip	bit manipulation instructions
+;; condmove	conditional moves
 ;; Classification of RVV instructions which will be added to each RVV .md pattern and used by scheduler.
 ;; rdvlenb     vector byte length vlenb csrr read
 ;; rdvl        vector length vl csrr read
@@ -324,7 +325,7 @@ (define_attr "type"
   "unknown,branch,jump,call,load,fpload,store,fpstore,
    mtc,mfc,const,arith,logical,shift,slt,imul,idiv,move,fmove,fadd,fmul,
    fmadd,fdiv,fcmp,fcvt,fsqrt,multi,auipc,sfb_alu,nop,ghost,bitmanip,rotate,
-   atomic,rdvlenb,rdvl,vsetvl,vlde,vste,vldm,vstm,vlds,vsts,
+   atomic,condmove,rdvlenb,rdvl,vsetvl,vlde,vste,vldm,vstm,vlds,vsts,
    vldux,vldox,vstux,vstox,vldff,vldr,vstr,
    vialu,viwalu,vext,vicalu,vshift,vnshift,vicmp,
    vimul,vidiv,viwmul,vimuladd,viwmuladd,vimerge,vimov,
@@ -2223,9 +2224,9 @@ (define_insn "*branch<mode>"
 (define_expand "mov<mode>cc"
   [(set (match_operand:GPR 0 "register_operand")
 	(if_then_else:GPR (match_operand 1 "comparison_operator")
-			  (match_operand:GPR 2 "register_operand")
+			  (match_operand:GPR 2 "reg_or_0_operand")
 			  (match_operand:GPR 3 "sfb_alu_operand")))]
-  "TARGET_SFB_ALU"
+  "TARGET_SFB_ALU || TARGET_XTHEADCONDMOV"
 {
   rtx cmp = operands[1];
   /* We only handle word mode integer compares for now.  */
diff --git a/gcc/config/riscv/thead.md b/gcc/config/riscv/thead.md
index 676d10b71d7..e9a6c1eeb71 100644
--- a/gcc/config/riscv/thead.md
+++ b/gcc/config/riscv/thead.md
@@ -36,3 +36,38 @@ (define_insn "*th_tst"
   "TARGET_XTHEADBS"
   "th.tst\t%0,%1,%2"
   [(set_attr "type" "bitmanip")])
+
+(define_insn "*th_cond_mov<GPR:mode><GPR2:mode>"
+  [(set (match_operand:GPR 0 "register_operand" "=r,r")
+	(if_then_else:GPR
+	 (match_operator 4 "equality_operator"
+		[(match_operand:GPR2 1 "register_operand" "r,r")
+		 (const_int 0)])
+	 (match_operand:GPR 2 "reg_or_0_operand" "rJ,0")
+	 (match_operand:GPR 3 "reg_or_0_operand" "0,rJ")))]
+  "TARGET_XTHEADCONDMOV"
+{
+  if (which_alternative == 0)
+    return "th.mv%C4z\t%0,%z2,%1";
+
+  /* Invert the condition and take else-block.  */
+  rtx_code code = GET_CODE (operands[4]);
+  code = (code == EQ) ? NE : EQ;
+  operands[4] = gen_rtx_fmt_ee (code, VOIDmode, const0_rtx, const0_rtx);
+  return "th.mv%C4z\t%0,%z3,%1";
+}
+  [(set_attr "type" "condmove")
+   (set_attr "mode" "<GPR:MODE>")])
+
+(define_insn "*th_cond_gpr_mov<GPR:mode><GPR2:mode>"
+  [(set (match_operand:GPR 0 "register_operand" "=r,r")
+	(if_then_else:GPR
+	 (match_operand:GPR2 1 "register_operand" "r,r")
+	 (match_operand:GPR 2 "reg_or_0_operand" "rJ,0")
+	 (match_operand:GPR 3 "reg_or_0_operand" "0,rJ")))]
+  "TARGET_XTHEADCONDMOV"
+  "@
+   th.mvnez\t%0,%z2,%1
+   th.mveqz\t%0,%z3,%1"
+  [(set_attr "type" "condmove")
+   (set_attr "mode" "<GPR:MODE>")])
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mveqz-imm-eqz.c b/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mveqz-imm-eqz.c
new file mode 100644
index 00000000000..c66ec7fadbb
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mveqz-imm-eqz.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc_xtheadcondmov -mabi=lp64" } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-Os" "-Og" } } */
+
+int
+not_int_int (int x, int cond)
+{
+  if (cond == 0)
+    return 1025;
+  return x;
+}
+
+long
+not_long_int (long x, int cond)
+{
+  if (cond == 0)
+    return 1025l;
+  return x;
+}
+
+int
+not_int_long (int x, long cond)
+{
+  if (cond == 0)
+    return 1025;
+  return x;
+}
+
+long
+not_long_long (long x, int cond)
+{
+  if (cond == 0)
+    return 1025l;
+  return x;
+}
+
+/* { dg-final { scan-assembler-times "th.mveqz" 4 } } */
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mveqz-imm-not.c b/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mveqz-imm-not.c
new file mode 100644
index 00000000000..c076dbca4ef
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mveqz-imm-not.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc_xtheadcondmov -mabi=lp64 -O2" } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-Os" "-Og" } } */
+
+int
+not_int_int (int x, int cond)
+{
+  if (!cond)
+    return 1025;
+  return x;
+}
+
+long
+not_long_int (long x, int cond)
+{
+  if (!cond)
+    return 1025l;
+  return x;
+}
+
+int
+not_int_long (int x, long cond)
+{
+  if (!cond)
+    return 1025;
+  return x;
+}
+
+long
+not_long_long (long x, int cond)
+{
+  if (!cond)
+    return 1025l;
+  return x;
+}
+
+/* { dg-final { scan-assembler-times "th.mveqz" 4 } } */
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mveqz-reg-eqz.c b/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mveqz-reg-eqz.c
new file mode 100644
index 00000000000..3e2e369bdb2
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mveqz-reg-eqz.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc_xtheadcondmov -mabi=lp64" } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-Os" "-Og" } } */
+
+int
+not_int_int (int x, int cond, int v)
+{
+  if (cond == 0)
+    return v;
+  return x;
+}
+
+long
+not_long_int (long x, int cond, long v)
+{
+  if (cond == 0)
+    return v;
+  return x;
+}
+
+int
+not_int_long (int x, long cond, int v)
+{
+  if (cond == 0)
+    return v;
+  return x;
+}
+
+long
+not_long_long (long x, int cond, long v)
+{
+  if (cond == 0)
+    return v;
+  return x;
+}
+
+/* { dg-final { scan-assembler-times "th.mveqz" 4 } } */
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mveqz-reg-not.c b/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mveqz-reg-not.c
new file mode 100644
index 00000000000..c387d1c5f98
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mveqz-reg-not.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc_xtheadcondmov -mabi=lp64 -O2" } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-Os" "-Og" } } */
+
+int
+not_int_int (int x, int cond, int v)
+{
+  if (!cond)
+    return v;
+  return x;
+}
+
+long
+not_long_int (long x, int cond, long v)
+{
+  if (!cond)
+    return v;
+  return x;
+}
+
+int
+not_int_long (int x, long cond, int v)
+{
+  if (!cond)
+    return v;
+  return x;
+}
+
+long
+not_long_long (long x, int cond, long v)
+{
+  if (!cond)
+    return v;
+  return x;
+}
+
+/* { dg-final { scan-assembler-times "th.mveqz" 4 } } */
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mvnez-imm-cond.c b/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mvnez-imm-cond.c
new file mode 100644
index 00000000000..95b396057da
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mvnez-imm-cond.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc_xtheadcondmov -mabi=lp64 -O2" } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-Os" "-Og" } } */
+
+int
+not_int_int (int x, int cond)
+{
+  if (cond)
+    return 1025;
+  return x;
+}
+
+long
+not_long_int (long x, int cond)
+{
+  if (cond)
+    return 1025l;
+  return x;
+}
+
+int
+not_int_long (int x, long cond)
+{
+  if (cond)
+    return 1025;
+  return x;
+}
+
+long
+not_long_long (long x, int cond)
+{
+  if (cond)
+    return 1025l;
+  return x;
+}
+
+/* { dg-final { scan-assembler-times "th.mvnez" 4 } } */
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mvnez-imm-nez.c b/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mvnez-imm-nez.c
new file mode 100644
index 00000000000..cc17f1bd82d
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mvnez-imm-nez.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc_xtheadcondmov -mabi=lp64" } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-Os" "-Og" } } */
+
+int
+not_int_int (int x, int cond)
+{
+  if (cond != 0)
+    return 1025;
+  return x;
+}
+
+long
+not_long_int (long x, int cond)
+{
+  if (cond != 0)
+    return 1025l;
+  return x;
+}
+
+int
+not_int_long (int x, long cond)
+{
+  if (cond != 0)
+    return 1025;
+  return x;
+}
+
+long
+not_long_long (long x, int cond)
+{
+  if (cond != 0)
+    return 1025l;
+  return x;
+}
+
+/* { dg-final { scan-assembler-times "th.mvnez" 4 } } */
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mvnez-reg-cond.c b/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mvnez-reg-cond.c
new file mode 100644
index 00000000000..732e892875b
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mvnez-reg-cond.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc_xtheadcondmov -mabi=lp64 -O2" } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-Os" "-Og" } } */
+
+int
+not_int_int (int x, int cond, int v)
+{
+  if (cond)
+    return v;
+  return x;
+}
+
+long
+not_long_int (long x, int cond, long v)
+{
+  if (cond)
+    return v;
+  return x;
+}
+
+int
+not_int_long (int x, long cond, int v)
+{
+  if (cond)
+    return v;
+  return x;
+}
+
+long
+not_long_long (long x, int cond, long v)
+{
+  if (cond)
+    return v;
+  return x;
+}
+
+/* { dg-final { scan-assembler-times "th.mvnez" 4 } } */
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mvnez-reg-nez.c b/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mvnez-reg-nez.c
new file mode 100644
index 00000000000..e369a972a16
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadcondmov-mvnez-reg-nez.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc_xtheadcondmov -mabi=lp64" } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-Os" "-Og" } } */
+
+int
+not_int_int (int x, int cond, int v)
+{
+  if (cond != 0)
+    return v;
+  return x;
+}
+
+long
+not_long_int (long x, int cond, long v)
+{
+  if (cond != 0)
+    return v;
+  return x;
+}
+
+int
+not_int_long (int x, long cond, int v)
+{
+  if (cond != 0)
+    return v;
+  return x;
+}
+
+long
+not_long_long (long x, int cond, long v)
+{
+  if (cond != 0)
+    return v;
+  return x;
+}
+
+/* { dg-final { scan-assembler-times "th.mvnez" 4 } } */
-- 
2.38.1