riscv: thead: Add support for the XTheadFMemIdx ISA extension

The XTheadFMemIdx ISA extension provides additional load and store
instructions for floating-point registers with new addressing modes.

The following memory accesses types are supported:
* load/store: [w,d] (single-precision FP, double-precision FP)

The following addressing modes are supported:
* register offset with additional immediate offset (4 instructions):
  flr<type>, fsr<type>
* zero-extended register offset with additional immediate offset
  (4 instructions): flur<type>, fsur<type>

These addressing modes are also part of the similar XTheadMemIdx
ISA extension support, whose code is reused and extended to support
floating-point registers.

One challenge that this patch needs to solve are GP registers in FP-mode
(e.g. "(reg:DF a2)"), which cannot be handled by the XTheadFMemIdx
instructions. Such registers are the result of independent
optimizations, which can happen after register allocation.
This patch uses a simple but efficient method to address this:
add a dependency for XTheadMemIdx to XTheadFMemIdx optimizations.
This allows to use the instructions from XTheadMemIdx in case
of such registers.

The added tests ensure that this feature won't regress without notice.
Testing: GCC regression test suite and SPEC CPU 2017 intrate (base&peak).

Signed-off-by: Christoph Müllner <christoph.muellner@vrull.eu>

gcc/ChangeLog:

	* config/riscv/riscv.cc (riscv_index_reg_class):
	Return GR_REGS for XTheadFMemIdx.
	(riscv_regno_ok_for_index_p): Add support for XTheadFMemIdx.
	* config/riscv/riscv.h (HARDFP_REG_P): New macro.
	* config/riscv/thead.cc (is_fmemidx_mode): New function.
	(th_memidx_classify_address_index): Add support for XTheadFMemIdx.
	(th_fmemidx_output_index): New function.
	(th_output_move): Add support for XTheadFMemIdx.
	* config/riscv/thead.md (TH_M_ANYF): New mode iterator.
	(TH_M_NOEXTF): Likewise.
	(*th_fmemidx_movsf_hardfloat): New INSN.
	(*th_fmemidx_movdf_hardfloat_rv64): Likewise.
	(*th_fmemidx_I_a): Likewise.
	(*th_fmemidx_I_c): Likewise.
	(*th_fmemidx_US_a): Likewise.
	(*th_fmemidx_US_c): Likewise.
	(*th_fmemidx_UZ_a): Likewise.
	(*th_fmemidx_UZ_c): Likewise.

gcc/testsuite/ChangeLog:

	* gcc.target/riscv/xtheadfmemidx-index-update.c: New test.
	* gcc.target/riscv/xtheadfmemidx-index-xtheadbb-update.c: New test.
	* gcc.target/riscv/xtheadfmemidx-index-xtheadbb.c: New test.
	* gcc.target/riscv/xtheadfmemidx-index.c: New test.
	* gcc.target/riscv/xtheadfmemidx-uindex-update.c: New test.
	* gcc.target/riscv/xtheadfmemidx-uindex-xtheadbb-update.c: New test.
	* gcc.target/riscv/xtheadfmemidx-uindex-xtheadbb.c: New test.
	* gcc.target/riscv/xtheadfmemidx-uindex.c: New test.

Signed-off-by: Christoph Müllner <christoph.muellner@vrull.eu>

12 files changed, 404 insertions, 5 deletions

diff --git a/gcc/config/riscv/riscv.cc b/gcc/config/riscv/riscv.cc
index de6d973..0148a4f 100644
--- a/gcc/config/riscv/riscv.cc
+++ b/gcc/config/riscv/riscv.cc
@@ -1084,7 +1084,7 @@ riscv_regno_mode_ok_for_base_p (int regno,
 enum reg_class
 riscv_index_reg_class ()
 {
-  if (TARGET_XTHEADMEMIDX)
+  if (TARGET_XTHEADMEMIDX || TARGET_XTHEADFMEMIDX)
     return GR_REGS;
 
   return NO_REGS;
@@ -1097,7 +1097,7 @@ riscv_index_reg_class ()
 int
 riscv_regno_ok_for_index_p (int regno)
 {
-  if (TARGET_XTHEADMEMIDX)
+  if (TARGET_XTHEADMEMIDX || TARGET_XTHEADFMEMIDX)
     return riscv_regno_mode_ok_for_base_p (regno, VOIDmode, 1);
 
   return 0;
diff --git a/gcc/config/riscv/riscv.h b/gcc/config/riscv/riscv.h
index eb162ab..1e9813b 100644
--- a/gcc/config/riscv/riscv.h
+++ b/gcc/config/riscv/riscv.h
@@ -372,6 +372,8 @@ ASM_MISA_SPEC
   ((unsigned int) ((int) (REGNO) - GP_REG_FIRST) < GP_REG_NUM)
 #define FP_REG_P(REGNO)  \
   ((unsigned int) ((int) (REGNO) - FP_REG_FIRST) < FP_REG_NUM)
+#define HARDFP_REG_P(REGNO)  \
+  ((REGNO) >= FP_REG_FIRST && (REGNO) <= FP_REG_LAST)
 #define V_REG_P(REGNO)  \
   ((unsigned int) ((int) (REGNO) - V_REG_FIRST) < V_REG_NUM)
 #define VL_REG_P(REGNO) ((REGNO) == VL_REGNUM)
diff --git a/gcc/config/riscv/thead.cc b/gcc/config/riscv/thead.cc
index 237d96f..a485fb1 100644
--- a/gcc/config/riscv/thead.cc
+++ b/gcc/config/riscv/thead.cc
@@ -614,6 +614,18 @@ is_memidx_mode (machine_mode mode)
   return false;
 }
 
+static bool
+is_fmemidx_mode (machine_mode mode)
+{
+  if (mode == SFmode && TARGET_HARD_FLOAT)
+    return true;
+
+  if (mode == DFmode && TARGET_DOUBLE_FLOAT)
+    return true;
+
+  return false;
+}
+
 /* Return true if X is a valid address for T-Head's memory addressing modes
    with scaled register offsets for machine mode MODE.
    If it is, fill in INFO appropriately (if non-NULL).
@@ -624,7 +636,8 @@ th_memidx_classify_address_index (struct riscv_address_info *info, rtx x,
 				  machine_mode mode, bool strict_p)
 {
   /* Ensure that the mode is supported.  */
-  if (!(TARGET_XTHEADMEMIDX && is_memidx_mode (mode)))
+  if (!(TARGET_XTHEADMEMIDX && is_memidx_mode (mode))
+      && !(TARGET_XTHEADFMEMIDX && is_fmemidx_mode (mode)))
     return false;
 
   if (GET_CODE (x) != PLUS)
@@ -781,6 +794,44 @@ th_memidx_output_index (rtx dest, rtx src, machine_mode mode, bool load)
   return "";
 }
 
+/* Provide a buffer for a th.flX/th.fluX/th.fsX/th.fsuX instruction
+   for the given MODE. If LOAD is true, a load instruction will be
+   provided (otherwise, a store instruction). If X is not suitable
+   return NULL.  */
+
+static const char *
+th_fmemidx_output_index (rtx dest, rtx src, machine_mode mode, bool load)
+{
+  struct riscv_address_info info;
+  char format[24];
+  rtx output_operands[2];
+  rtx x = th_get_move_mem_addr (dest, src, load);
+
+  /* Validate x.  */
+  if (!th_memidx_classify_address_index (&info, x, mode, false))
+    return NULL;
+
+  int index = exact_log2 (GET_MODE_SIZE (mode).to_constant ()) - 2;
+  bool uindex = info.type == ADDRESS_REG_UREG;
+
+  const char *const insn[][2] = {
+    {
+      "th.fs%srw\t%%z1,%%0",
+      "th.fs%srd\t%%z1,%%0"
+    },
+    {
+      "th.fl%srw\t%%0,%%1",
+      "th.fl%srd\t%%0,%%1"
+    }
+  };
+
+  snprintf (format, sizeof (format), insn[load][index], uindex ? "u" : "");
+  output_operands[0] = dest;
+  output_operands[1] = src;
+  output_asm_insn (format, output_operands);
+  return "";
+}
+
 /* Return true if X is a valid address for T-Head's memory addressing modes
    for machine mode MODE.  If it is, fill in INFO appropriately (if non-NULL).
    If STRICT_P is true then REG_OK_STRICT is in effect.  */
@@ -831,24 +882,36 @@ th_output_move (rtx dest, rtx src)
 
   if (dest_code == REG && src_code == MEM)
     {
-      if (GET_MODE_CLASS (mode) == MODE_INT)
+      if (GET_MODE_CLASS (mode) == MODE_INT
+	  || (GET_MODE_CLASS (mode) == MODE_FLOAT && GP_REG_P (REGNO (dest))))
 	{
 	  if ((insn = th_memidx_output_index (dest, src, mode, true)))
 	    return insn;
 	  if ((insn = th_memidx_output_modify (dest, src, mode, true)))
 	    return insn;
 	}
+      else if (GET_MODE_CLASS (mode) == MODE_FLOAT && HARDFP_REG_P (REGNO (dest)))
+	{
+	  if ((insn = th_fmemidx_output_index (dest, src, mode, true)))
+	    return insn;
+	}
     }
   else if (dest_code == MEM && (src_code == REG || src == CONST0_RTX (mode)))
     {
       if (GET_MODE_CLASS (mode) == MODE_INT
-	  || src == CONST0_RTX (mode))
+	  || src == CONST0_RTX (mode)
+	  || (GET_MODE_CLASS (mode) == MODE_FLOAT && GP_REG_P (REGNO (src))))
 	{
 	  if ((insn = th_memidx_output_index (dest, src, mode, false)))
 	    return insn;
 	  if ((insn = th_memidx_output_modify (dest, src, mode, false)))
 	    return insn;
 	}
+      else if (GET_MODE_CLASS (mode) == MODE_FLOAT && HARDFP_REG_P (REGNO (src)))
+	{
+	  if ((insn = th_fmemidx_output_index (dest, src, mode, false)))
+	    return insn;
+	}
     }
   return NULL;
 }
diff --git a/gcc/config/riscv/thead.md b/gcc/config/riscv/thead.md
index dfcb6d9..2babfaf 100644
--- a/gcc/config/riscv/thead.md
+++ b/gcc/config/riscv/thead.md
@@ -587,15 +587,24 @@
   [(set_attr "move_type" "shift_shift,load,load,load,load,load")
    (set_attr "mode" "<SUPERQI:MODE>")])
 
+;; All modes that are supported by XTheadMemIdx
 (define_mode_iterator TH_M_ANYI [(QI "TARGET_XTHEADMEMIDX")
                                  (HI "TARGET_XTHEADMEMIDX")
                                  (SI "TARGET_XTHEADMEMIDX")
                                  (DI "TARGET_64BIT && TARGET_XTHEADMEMIDX")])
 
+;; All modes that are supported by XTheadFMemIdx
+(define_mode_iterator TH_M_ANYF [(SF "TARGET_HARD_FLOAT && TARGET_XTHEADFMEMIDX")
+                                 (DF "TARGET_DOUBLE_FLOAT && TARGET_XTHEADFMEMIDX")])
+
 ;; All non-extension modes that are supported by XTheadMemIdx
 (define_mode_iterator TH_M_NOEXTI [(SI "!TARGET_64BIT && TARGET_XTHEADMEMIDX")
                                    (DI "TARGET_64BIT && TARGET_XTHEADMEMIDX")])
 
+;; All non-extension modes that are supported by XTheadFMemIdx
+(define_mode_iterator TH_M_NOEXTF [(SF "TARGET_HARD_FLOAT && TARGET_XTHEADFMEMIDX")
+                                   (DF "TARGET_DOUBLE_FLOAT && TARGET_XTHEADFMEMIDX")])
+
 ;; XTheadMemIdx optimizations
 ;; All optimizations attempt to improve the operand utilization of
 ;; XTheadMemIdx instructions, where one sign or zero extended
@@ -812,4 +821,156 @@
         (match_dup 0))]
 )
 
+;; XTheadFMemIdx
+
+(define_insn "*th_fmemidx_movsf_hardfloat"
+  [(set (match_operand:SF 0 "nonimmediate_operand" "=f,th_m_mir,f,th_m_miu")
+	(match_operand:SF 1 "move_operand"         " th_m_mir,f,th_m_miu,f"))]
+  "TARGET_HARD_FLOAT && TARGET_XTHEADFMEMIDX
+   && (register_operand (operands[0], SFmode)
+       || reg_or_0_operand (operands[1], SFmode))"
+  { return riscv_output_move (operands[0], operands[1]); }
+  [(set_attr "move_type" "fpload,fpstore,fpload,fpstore")
+   (set_attr "mode" "SF")])
+
+(define_insn "*th_fmemidx_movdf_hardfloat_rv64"
+  [(set (match_operand:DF 0 "nonimmediate_operand" "=f,th_m_mir,f,th_m_miu")
+	(match_operand:DF 1 "move_operand"         " th_m_mir,f,th_m_miu,f"))]
+  "TARGET_64BIT && TARGET_DOUBLE_FLOAT && TARGET_XTHEADFMEMIDX
+   && (register_operand (operands[0], DFmode)
+       || reg_or_0_operand (operands[1], DFmode))"
+  { return riscv_output_move (operands[0], operands[1]); }
+  [(set_attr "move_type" "fpload,fpstore,fpload,fpstore")
+   (set_attr "mode" "DF")])
+
+;; XTheadFMemIdx optimizations
+;; Similar like XTheadMemIdx optimizations, but less cases.
+;; Note, that we might get GP registers in FP-mode (reg:DF a2)
+;; which cannot be handled by the XTheadFMemIdx instructions.
+;; This might even happend after register allocation.
+;; We could implement splitters that undo the combiner results
+;; if "after_reload && !HARDFP_REG_P (operands[0])", but this
+;; raises even more questions (e.g. split into what?).
+;; So let's solve this by simply requiring XTheadMemIdx
+;; which provides the necessary instructions to cover this case.
+
+(define_insn_and_split "*th_fmemidx_I_a"
+  [(set (match_operand:TH_M_NOEXTF 0 "register_operand" "=f")
+        (mem:TH_M_NOEXTF (plus:X
+          (mult:X (match_operand:X 1 "register_operand" "r")
+                  (match_operand:QI 2 "immediate_operand" "i"))
+          (match_operand:X 3 "register_operand" "r"))))]
+  "TARGET_XTHEADMEMIDX && TARGET_XTHEADFMEMIDX
+   && CONST_INT_P (operands[2])
+   && pow2p_hwi (INTVAL (operands[2]))
+   && IN_RANGE (exact_log2 (INTVAL (operands[2])), 1, 3)"
+  "#"
+  "&& 1"
+  [(set (match_dup 0)
+        (mem:TH_M_NOEXTF (plus:X
+          (match_dup 3)
+          (ashift:X (match_dup 1) (match_dup 2)))))]
+  { operands[2] = GEN_INT (exact_log2 (INTVAL (operands [2])));
+  }
+)
+
+(define_insn_and_split "*th_fmemidx_I_c"
+  [(set (mem:TH_M_ANYF (plus:X
+          (mult:X (match_operand:X 1 "register_operand" "r")
+                  (match_operand:QI 2 "immediate_operand" "i"))
+          (match_operand:X 3 "register_operand" "r")))
+        (match_operand:TH_M_ANYF 0 "register_operand" "f"))]
+  "TARGET_XTHEADMEMIDX && TARGET_XTHEADFMEMIDX
+   && CONST_INT_P (operands[2])
+   && pow2p_hwi (INTVAL (operands[2]))
+   && IN_RANGE (exact_log2 (INTVAL (operands[2])), 1, 3)"
+  "#"
+  "&& 1"
+  [(set (mem:TH_M_ANYF (plus:X
+          (match_dup 3)
+          (ashift:X (match_dup 1) (match_dup 2))))
+        (match_dup 0))]
+  { operands[2] = GEN_INT (exact_log2 (INTVAL (operands [2])));
+  }
+)
+
+(define_insn_and_split "*th_fmemidx_US_a"
+  [(set (match_operand:TH_M_NOEXTF 0 "register_operand" "=f")
+        (mem:TH_M_NOEXTF (plus:DI
+          (and:DI
+            (mult:DI (match_operand:DI 1 "register_operand" "r")
+                     (match_operand:QI 2 "immediate_operand" "i"))
+            (match_operand:DI 3 "immediate_operand" "i"))
+          (match_operand:DI 4 "register_operand" "r"))))]
+  "TARGET_64BIT && TARGET_XTHEADMEMIDX && TARGET_XTHEADFMEMIDX
+   && CONST_INT_P (operands[2])
+   && pow2p_hwi (INTVAL (operands[2]))
+   && IN_RANGE (exact_log2 (INTVAL (operands[2])), 1, 3)
+   && CONST_INT_P (operands[3])
+   && (INTVAL (operands[3]) >> exact_log2 (INTVAL (operands[2]))) == 0xffffffff"
+  "#"
+  "&& 1"
+  [(set (match_dup 0)
+        (mem:TH_M_NOEXTF (plus:DI
+          (match_dup 4)
+          (ashift:DI (zero_extend:DI (match_dup 1)) (match_dup 2)))))]
+  { operands[1] = gen_lowpart (SImode, operands[1]);
+    operands[2] = GEN_INT (exact_log2 (INTVAL (operands [2])));
+  }
+)
+
+(define_insn_and_split "*th_fmemidx_US_c"
+  [(set (mem:TH_M_ANYF (plus:DI
+          (and:DI
+            (mult:DI (match_operand:DI 1 "register_operand" "r")
+                     (match_operand:QI 2 "immediate_operand" "i"))
+            (match_operand:DI 3 "immediate_operand" "i"))
+          (match_operand:DI 4 "register_operand" "r")))
+        (match_operand:TH_M_ANYF 0 "register_operand" "f"))]
+  "TARGET_64BIT && TARGET_XTHEADMEMIDX && TARGET_XTHEADFMEMIDX
+   && CONST_INT_P (operands[2])
+   && pow2p_hwi (INTVAL (operands[2]))
+   && IN_RANGE (exact_log2 (INTVAL (operands[2])), 1, 3)
+   && CONST_INT_P (operands[3])
+   && (INTVAL (operands[3]) >> exact_log2 (INTVAL (operands[2]))) == 0xffffffff"
+  "#"
+  "&& 1"
+  [(set (mem:TH_M_ANYF (plus:DI
+          (match_dup 4)
+          (ashift:DI (zero_extend:DI (match_dup 1)) (match_dup 2))))
+        (match_dup 0))]
+  { operands[1] = gen_lowpart (SImode, operands[1]);
+    operands[2] = GEN_INT (exact_log2 (INTVAL (operands [2])));
+  }
+)
+
+(define_insn_and_split "*th_fmemidx_UZ_a"
+  [(set (match_operand:TH_M_NOEXTF 0 "register_operand" "=f")
+        (mem:TH_M_NOEXTF (plus:DI
+          (zero_extend:DI (match_operand:SI 1 "register_operand" "r"))
+          (match_operand:DI 2 "register_operand" "r"))))]
+  "TARGET_64BIT && TARGET_XTHEADMEMIDX && TARGET_XTHEADFMEMIDX
+   && (!HARD_REGISTER_NUM_P (REGNO (operands[0])) || HARDFP_REG_P (REGNO (operands[0])))"
+  "#"
+  "&& 1"
+  [(set (match_dup 0)
+        (mem:TH_M_NOEXTF (plus:DI
+          (match_dup 2)
+          (zero_extend:DI (match_dup 1)))))]
+)
+
+(define_insn_and_split "*th_fmemidx_UZ_c"
+  [(set (mem:TH_M_ANYF (plus:DI
+          (zero_extend:DI (match_operand:SI 1 "register_operand" "r"))
+          (match_operand:DI 2 "register_operand" "r")))
+        (match_operand:TH_M_ANYF 0 "register_operand" "f"))]
+  "TARGET_64BIT && TARGET_XTHEADMEMIDX && TARGET_XTHEADFMEMIDX"
+  "#"
+  "&& 1"
+  [(set (mem:TH_M_ANYF (plus:DI
+          (match_dup 2)
+          (zero_extend:DI (match_dup 1))))
+        (match_dup 0))]
+)
+
 (include "thead-peephole.md")
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-index-update.c b/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-index-update.c
new file mode 100644
index 0000000..24bbb63
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-index-update.c
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-Og" } } */
+/* { dg-options "-march=rv64gc_xtheadmemidx_xtheadfmemidx" { target { rv64 } } } */
+/* { dg-options "-march=rv32imafc_xtheadmemidx_xtheadfmemidx -mabi=ilp32f" { target { rv32 } } } */
+
+#include "xtheadmemidx-helpers.h"
+
+LR_REG_IMM_UPD(float, 0)
+#if __riscv_xlen == 64
+LR_REG_IMM_UPD(double, 2)
+#endif
+
+SR_REG_IMM_UPD(float, 1)
+#if __riscv_xlen == 64
+SR_REG_IMM_UPD(double, 3)
+#endif
+
+/* If the shifted value is used later, we cannot eliminate it.  */
+/* { dg-final { scan-assembler-times {\mslli\M} 1 { target { rv32 } } } } */
+/* { dg-final { scan-assembler-times {\mslli\M} 3 { target { rv64 } } } } */
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-index-xtheadbb-update.c b/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-index-xtheadbb-update.c
new file mode 100644
index 0000000..3b931a4
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-index-xtheadbb-update.c
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-Og" } } */
+/* { dg-options "-march=rv64gc_xtheadbb_xtheadmemidx_xtheadfmemidx" { target { rv64 } } } */
+/* { dg-options "-march=rv32imafc_xtheadbb_xtheadmemidx_xtheadfmemidx -mabi=ilp32f" { target { rv32 } } } */
+
+#include "xtheadmemidx-helpers.h"
+
+LR_REG_IMM_UPD(float, 0)
+#if __riscv_xlen == 64
+LR_REG_IMM_UPD(double, 2)
+#endif
+
+SR_REG_IMM_UPD(float, 1)
+#if __riscv_xlen == 64
+SR_REG_IMM_UPD(double, 3)
+#endif
+
+/* If the shifted value is used later, we cannot eliminate it.  */
+/* { dg-final { scan-assembler-times {\mslli\M} 1 { target { rv32 } } } } */
+/* { dg-final { scan-assembler-times {\mslli\M} 3 { target { rv64 } } } } */
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-index-xtheadbb.c b/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-index-xtheadbb.c
new file mode 100644
index 0000000..4885860
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-index-xtheadbb.c
@@ -0,0 +1,22 @@
+/* { dg-do compile } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-Og" } } */
+/* { dg-options "-march=rv64gc_xtheadbb_xtheadmemidx_xtheadfmemidx" { target { rv64 } } } */
+/* { dg-options "-march=rv32imafc_xtheadbb_xtheadmemidx_xtheadfmemidx -mabi=ilp32f" { target { rv32 } } } */
+
+#include "xtheadmemidx-helpers.h"
+
+LR_REG_IMM(float, 0)
+/* { dg-final { scan-assembler-times {\mth\.flrw\t[^\n\r]*0\M} 1 } } */
+#if __riscv_xlen == 64
+LR_REG_IMM(double, 2)
+/* { dg-final { scan-assembler-times {\mth\.flrd\t[^\n\r]*2\M} 1 { target { rv64 } } } } */
+#endif
+
+SR_REG_IMM(float, 1)
+/* { dg-final { scan-assembler-times {\mth\.fsrw\t[^\n\r]*1\M} 1 } } */
+#if __riscv_xlen == 64
+SR_REG_IMM(double, 3)
+/* { dg-final { scan-assembler-times {\mth\.fsrd\t[^\n\r]*3\M} 1 { target { rv64 } } } } */
+#endif
+
+/* { dg-final { scan-assembler-not "slli" } } */
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-index.c b/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-index.c
new file mode 100644
index 0000000..1bb231a
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-index.c
@@ -0,0 +1,22 @@
+/* { dg-do compile } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-Og" } } */
+/* { dg-options "-march=rv64gc_xtheadmemidx_xtheadfmemidx" { target { rv64 } } } */
+/* { dg-options "-march=rv32imafc_xtheadmemidx_xtheadfmemidx -mabi=ilp32f" { target { rv32 } } } */
+
+#include "xtheadmemidx-helpers.h"
+
+LR_REG_IMM(float, 0)
+/* { dg-final { scan-assembler-times {\mth\.flrw\t[^\n\r]*0\M} 1 } } */
+#if __riscv_xlen == 64
+LR_REG_IMM(double, 2)
+/* { dg-final { scan-assembler-times {\mth\.flrd\t[^\n\r]*2\M} 1 { target { rv64 } } } } */
+#endif
+
+SR_REG_IMM(float, 1)
+/* { dg-final { scan-assembler-times {\mth\.fsrw\t[^\n\r]*1\M} 1 } } */
+#if __riscv_xlen == 64
+SR_REG_IMM(double, 3)
+/* { dg-final { scan-assembler-times {\mth\.fsrd\t[^\n\r]*3\M} 1 { target { rv64 } } } } */
+#endif
+
+/* { dg-final { scan-assembler-not {\mslli\M} } } */
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-uindex-update.c b/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-uindex-update.c
new file mode 100644
index 0000000..bc50fa7
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-uindex-update.c
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-Og" } } */
+/* { dg-options "-march=rv64gc_xtheadmemidx_xtheadfmemidx" { target { rv64 } } } */
+/* { dg-options "-march=rv32imafc_xtheadmemidx_xtheadfmemidx -mabi=ilp32f" { target { rv32 } } } */
+
+#include "xtheadmemidx-helpers.h"
+
+LRU_REG_IMM_UPD(float, 0)
+#if __riscv_xlen == 64
+LRU_REG_IMM_UPD(double, 2)
+#endif
+
+SRU_REG_IMM_UPD(float, 1)
+#if __riscv_xlen == 64
+SRU_REG_IMM_UPD(double, 3)
+#endif
+
+/* If the shifted value is used later, we cannot eliminate it.  */
+/* { dg-final { scan-assembler-times {\mslli\M} 1 { target { rv32 } } } } */
+/* { dg-final { scan-assembler-times {\mslli\M} 3 { target { rv64 } } } } */
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-uindex-xtheadbb-update.c b/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-uindex-xtheadbb-update.c
new file mode 100644
index 0000000..242be7a
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-uindex-xtheadbb-update.c
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-Og" } } */
+/* { dg-options "-march=rv64gc_xtheadbb_xtheadmemidx_xtheadfmemidx" { target { rv64 } } } */
+/* { dg-options "-march=rv32imafc_xtheadbb_xtheadmemidx_xtheadfmemidx -mabi=ilp32f" { target { rv32 } } } */
+
+#include "xtheadmemidx-helpers.h"
+
+LRU_REG_IMM_UPD(float, 0)
+#if __riscv_xlen == 64
+LRU_REG_IMM_UPD(double, 2)
+#endif
+
+SRU_REG_IMM_UPD(float, 1)
+#if __riscv_xlen == 64
+SRU_REG_IMM_UPD(double, 3)
+#endif
+
+/* If the shifted value is used later, we cannot eliminate it.  */
+/* { dg-final { scan-assembler-times {\mslli\M} 1 { target { rv32 } } } } */
+/* { dg-final { scan-assembler-times {\mslli\M} 3 { target { rv64 } } } } */
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-uindex-xtheadbb.c b/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-uindex-xtheadbb.c
new file mode 100644
index 0000000..e2a4f36
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-uindex-xtheadbb.c
@@ -0,0 +1,24 @@
+/* { dg-do compile } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-Og" } } */
+/* { dg-options "-march=rv64gc_xtheadbb_xtheadmemidx_xtheadfmemidx" { target { rv64 } } } */
+/* { dg-options "-march=rv32imafc_xtheadbb_xtheadmemidx_xtheadfmemidx -mabi=ilp32f" { target { rv32 } } } */
+
+#include "xtheadmemidx-helpers.h"
+
+LRU_REG_IMM(float, 0)
+/* { dg-final { scan-assembler-times {\mth\.flurw\t[^\n\r]*0\M} 1 { target { rv64 } } } } */
+/* { dg-final { scan-assembler-times {\mth\.flrw\t[^\n\r]*0\M} 1 { target { rv32 } } } } */
+#if __riscv_xlen == 64
+LRU_REG_IMM(double, 2)
+/* { dg-final { scan-assembler-times {\mth\.flurd\t[^\n\r]*2\M} 1 { target { rv64 } } } } */
+#endif
+
+SRU_REG_IMM(float, 1)
+/* { dg-final { scan-assembler-times {\mth\.fsurw\t[^\n\r]*1\M} 1 { target { rv64 } } } } */
+/* { dg-final { scan-assembler-times {\mth\.fsrw\t[^\n\r]*1\M} 1 { target { rv32 } } } } */
+#if __riscv_xlen == 64
+SRU_REG_IMM(double, 3)
+/* { dg-final { scan-assembler-times {\mth\.fsurd\t[^\n\r]*3\M} 1 { target { rv64 } } } } */
+#endif
+
+/* { dg-final { scan-assembler-not {\mslli\M} } } */
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-uindex.c b/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-uindex.c
new file mode 100644
index 0000000..32783eb
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadfmemidx-uindex.c
@@ -0,0 +1,25 @@
+/* { dg-do compile } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-Og" } } */
+/* { dg-options "-march=rv64gc_xtheadmemidx_xtheadfmemidx" { target { rv64 } } } */
+/* { dg-options "-march=rv32imafc_xtheadmemidx_xtheadfmemidx -mabi=ilp32f" { target { rv32 } } } */
+
+#include "xtheadmemidx-helpers.h"
+
+LRU_REG_IMM(float, 0)
+/* { dg-final { scan-assembler-times {\mth\.flurw\t[^\n\r]*0\M} 1 { target { rv64 } } } } */
+/* { dg-final { scan-assembler-times {\mth\.flrw\t[^\n\r]*0\M} 1 { target { rv32 } } } } */
+#if __riscv_xlen == 64
+LRU_REG_IMM(double, 2)
+/* { dg-final { scan-assembler-times {\mth\.flurd\t[^\n\r]*2\M} 1 { target { rv64 } } } } */
+#endif
+
+SRU_REG_IMM(float, 1)
+/* { dg-final { scan-assembler-times {\mth\.fsurw\t[^\n\r]*1\M} 1 { target { rv64 } } } } */
+/* { dg-final { scan-assembler-times {\mth\.fsrw\t[^\n\r]*1\M} 1 { target { rv32 } } } } */
+#if __riscv_xlen == 64
+SRU_REG_IMM(double, 3)
+/* { dg-final { scan-assembler-times {\mth\.fsurd\t[^\n\r]*3\M} 1 { target { rv64 } } } } */
+#endif
+
+/* { dg-final { scan-assembler-not {\mslli\M} } } */
+