refactor(testgen): centralize dyn frm random selection in generate_random_params

Move csr_frm_val random assignment from each formatter into generate_random_params,
allow RNE (mode 0) in random selection, and simplify cp_csr_frm comment.

Author: dev-aditya-hub

generators/testgen/src/testgen/coverpoints/cp_csr_frm.py

@@ -21,10 +21,7 @@ def make_frm(instr_name: str, instr_type: str, coverpoint: str, test_data: TestD
     if coverpoint != "cp_csr_frm":
         raise ValueError(f"Unknown cp_csr_frm coverpoint variant: {coverpoint} for {instr_name}")
 
-    # Test each valid fcsr.frm value (0-4) via the dynamic rounding mode path (rm=111).
-    # Passing frm="dyn" encodes rm=111 in the instruction; csr_frm_val tells the formatter
-    # which exact value to write into fcsr.frm before the instruction executes, and the
-    # formatter restores fcsr.frm=0 in check — no ordering dependency needed.
+    # Test each valid fcsr.frm value (0-4) via dynamic rounding mode (rm=111 in the encoding).
     frm_modes = (("rne", 0), ("rtz", 1), ("rdn", 2), ("rup", 3), ("rmm", 4))
     test_chunks: list[TestChunk] = []
     for frm_name, frm_val in frm_modes:

generators/testgen/src/testgen/data/params.py

@@ -61,7 +61,7 @@ class InstructionParams:
 
     # Flags
     frm: str | None = None  # Floating-point rounding mode tests
-    csr_frm_val: int | None = None  # Explicit fcsr.frm value for dyn tests; None means random non-RNE
+    csr_frm_val: int | None = None  # fcsr.frm value to set when frm="dyn"; None means randomly chosen
     aqrl: str | None = None  # Acquire/Release for atomic operations
     fflags: int | None = None  # Floating-point result flags
 

generators/testgen/src/testgen/formatters/params.py

@@ -69,6 +69,10 @@ def generate_random_params(
     """
     params = InstructionParams(**fixed_params)
 
+    # Assign a random fcsr.frm value for dynamic rounding mode tests if not already set
+    if params.frm == "dyn" and params.csr_frm_val is None:
+        params.csr_frm_val = random_range(0, 4)
+
     # Get the required parameters for this instruction type (extracted from formatters)
     instr_type_config = get_instr_type_config(instr_type)
     required_params = instr_type_config.required_params

generators/testgen/src/testgen/formatters/types/f2x_type.py

@@ -5,8 +5,6 @@
 # SPDX-License-Identifier: Apache-2.0
 ##################################
 
-import random
-
 from testgen.asm.helpers import load_float_reg, write_sigupd
 from testgen.data.params import InstructionParams
 from testgen.data.state import TestData
@@ -41,7 +39,7 @@ def format_f2x_type(
         write_sigupd(None, test_data, "fflags"),
     ]
     if params.frm == "dyn":
-        fcsr_frm = params.csr_frm_val if params.csr_frm_val is not None else random.choice([1, 2, 3, 4])
-        setup.append(f"fsrmi {fcsr_frm}")
+        assert params.csr_frm_val is not None
+        setup.append(f"fsrmi {params.csr_frm_val}")
         check.append("fsrmi 0x0")
     return (setup, test, check)

generators/testgen/src/testgen/formatters/types/fi_type.py

@@ -5,8 +5,6 @@
 # SPDX-License-Identifier: Apache-2.0
 ##################################
 
-import random
-
 from testgen.asm.helpers import load_float_reg, write_sigupd
 from testgen.data.params import InstructionParams
 from testgen.data.state import TestData
@@ -32,7 +30,7 @@ def format_fi_type(
     ]
     check = [write_sigupd(params.fd, test_data, "float")]
     if params.frm == "dyn":
-        fcsr_frm = params.csr_frm_val if params.csr_frm_val is not None else random.choice([1, 2, 3, 4])
-        setup.append(f"fsrmi {fcsr_frm}")
+        assert params.csr_frm_val is not None
+        setup.append(f"fsrmi {params.csr_frm_val}")
         check.append("fsrmi 0x0")
     return (setup, test, check)

generators/testgen/src/testgen/formatters/types/fr4_type.py

@@ -5,8 +5,6 @@
 # SPDX-License-Identifier: Apache-2.0
 ##################################
 
-import random
-
 from testgen.asm.helpers import load_float_reg, write_sigupd
 from testgen.data.params import InstructionParams
 from testgen.data.state import TestData
@@ -36,7 +34,7 @@ def format_fr4_type(
     ]
     check = [write_sigupd(params.fd, test_data, "float")]
     if params.frm == "dyn":
-        fcsr_frm = params.csr_frm_val if params.csr_frm_val is not None else random.choice([1, 2, 3, 4])
-        setup.append(f"fsrmi {fcsr_frm}")
+        assert params.csr_frm_val is not None
+        setup.append(f"fsrmi {params.csr_frm_val}")
         check.append("fsrmi 0x0")
     return (setup, test, check)

generators/testgen/src/testgen/formatters/types/fr_type.py

@@ -5,8 +5,6 @@
 # SPDX-License-Identifier: Apache-2.0
 ##################################
 
-import random
-
 from testgen.asm.helpers import load_float_reg, write_sigupd
 from testgen.data.params import InstructionParams
 from testgen.data.state import TestData
@@ -34,7 +32,7 @@ def format_fr_type(
     ]
     check = [write_sigupd(params.fd, test_data, "float")]
     if params.frm == "dyn":
-        fcsr_frm = params.csr_frm_val if params.csr_frm_val is not None else random.choice([1, 2, 3, 4])
-        setup.append(f"fsrmi {fcsr_frm}")
+        assert params.csr_frm_val is not None
+        setup.append(f"fsrmi {params.csr_frm_val}")
         check.append("fsrmi 0x0")
     return (setup, test, check)

generators/testgen/src/testgen/formatters/types/x2f_type.py

@@ -5,8 +5,6 @@
 # SPDX-License-Identifier: Apache-2.0
 ##################################
 
-import random
-
 from testgen.asm.helpers import load_int_reg, write_sigupd
 from testgen.data.params import InstructionParams
 from testgen.data.state import TestData
@@ -32,7 +30,7 @@ def format_x2f_type(
     ]
     check = [write_sigupd(params.fd, test_data, "float")]
     if params.frm == "dyn":
-        fcsr_frm = params.csr_frm_val if params.csr_frm_val is not None else random.choice([1, 2, 3, 4])
-        setup.append(f"fsrmi {fcsr_frm}")
+        assert params.csr_frm_val is not None
+        setup.append(f"fsrmi {params.csr_frm_val}")
         check.append("fsrmi 0x0")
     return (setup, test, check)