From 28ac169cfea1384cb44c4a414acc2f59cff0e9ca Mon Sep 17 00:00:00 2001
From: Eyck-Alexander Jentzsch <alex@minres.com>
Date: Wed, 19 Feb 2025 10:10:41 +0100
Subject: [PATCH] adds narrowing fixed point instructions

---
 gen_input/templates/interp/CORENAME.cpp.gtl |  26 ++++
 src/vm/vector_functions.h                   |   6 +-
 src/vm/vector_functions.hpp                 | 127 ++++++++++++--------
 3 files changed, 104 insertions(+), 55 deletions(-)

diff --git a/gen_input/templates/interp/CORENAME.cpp.gtl b/gen_input/templates/interp/CORENAME.cpp.gtl
index df29e80..234adbc 100644
--- a/gen_input/templates/interp/CORENAME.cpp.gtl
+++ b/gen_input/templates/interp/CORENAME.cpp.gtl
@@ -441,6 +441,32 @@ if(vector != null) {%>
                 throw new std::runtime_error("Unsupported sew bit value");
         }
     }
+    bool sat_vector_vector_vw(uint8_t* V, uint8_t funct6, uint8_t funct3, uint64_t vl, uint64_t vstart, softvector::vtype_t vtype, uint64_t vxrm, bool vm, uint8_t vd, uint8_t vs2, uint8_t vs1, uint8_t sew_val){
+        switch(sew_val){
+            case 0b000:
+                return softvector::sat_vector_vector_op<${vlen}, uint8_t, uint16_t>(V, funct6, funct3, vl, vstart, vtype, vxrm, vm, vd, vs2, vs1);
+            case 0b001:
+                return softvector::sat_vector_vector_op<${vlen}, uint16_t, uint32_t>(V, funct6, funct3, vl, vstart, vtype, vxrm, vm, vd, vs2, vs1);
+            case 0b010:
+                return softvector::sat_vector_vector_op<${vlen}, uint32_t, uint64_t>(V, funct6, funct3, vl, vstart, vtype, vxrm, vm, vd, vs2, vs1);
+            case 0b011: // would require 128 bits vs2 value
+            default:
+                throw new std::runtime_error("Unsupported sew bit value");
+        }
+    }
+    bool sat_vector_imm_vw(uint8_t* V, uint8_t funct6, uint8_t funct3, uint64_t vl, uint64_t vstart, softvector::vtype_t vtype, uint64_t vxrm, bool vm, uint8_t vd, uint8_t vs2, int64_t imm, uint8_t sew_val){
+        switch(sew_val){
+            case 0b000:
+                return softvector::sat_vector_imm_op<${vlen}, uint8_t, uint16_t>(V, funct6, funct3, vl, vstart, vtype, vxrm, vm, vd, vs2, imm);
+            case 0b001:
+                return softvector::sat_vector_imm_op<${vlen}, uint16_t, uint32_t>(V, funct6, funct3, vl, vstart, vtype, vxrm, vm, vd, vs2, imm);
+            case 0b010:
+                return softvector::sat_vector_imm_op<${vlen}, uint32_t, uint64_t>(V, funct6, funct3, vl, vstart, vtype, vxrm, vm, vd, vs2, imm);
+            case 0b011: // would require 128 bits vs2 value
+            default:
+                throw new std::runtime_error("Unsupported sew bit value");
+        }
+    }
 <%}%>
     uint64_t fetch_count{0};
     uint64_t tval{0};
diff --git a/src/vm/vector_functions.h b/src/vm/vector_functions.h
index 6416c97..65ea400 100644
--- a/src/vm/vector_functions.h
+++ b/src/vm/vector_functions.h
@@ -91,12 +91,12 @@ void carry_vector_vector_op(uint8_t* V, unsigned funct, uint64_t vl, uint64_t vs
 template <unsigned VLEN, typename elem_t>
 void carry_vector_imm_op(uint8_t* V, unsigned funct, uint64_t vl, uint64_t vstart, vtype_t vtype, bool vm, unsigned vd, unsigned vs2,
                          typename std::make_signed<elem_t>::type imm);
-template <unsigned VLEN, typename dest_elem_t, typename src_elem_t = dest_elem_t>
+template <unsigned VLEN, typename dest_elem_t, typename src2_elem_t = dest_elem_t, typename src1_elem_t = dest_elem_t>
 bool sat_vector_vector_op(uint8_t* V, unsigned funct6, unsigned funct3, uint64_t vl, uint64_t vstart, vtype_t vtype, int64_t vxrm, bool vm,
                           unsigned vd, unsigned vs2, unsigned vs1);
-template <unsigned VLEN, typename dest_elem_t, typename src_elem_t = dest_elem_t>
+template <unsigned VLEN, typename dest_elem_t, typename src2_elem_t = dest_elem_t, typename src1_elem_t = dest_elem_t>
 bool sat_vector_imm_op(uint8_t* V, unsigned funct6, unsigned funct3, uint64_t vl, uint64_t vstart, vtype_t vtype, int64_t vxrm, bool vm,
-                       unsigned vd, unsigned vs2, typename std::make_signed<src_elem_t>::type imm);
+                       unsigned vd, unsigned vs2, typename std::make_signed<src1_elem_t>::type imm);
 } // namespace softvector
 #include "vm/vector_functions.hpp"
 #endif /* _VM_VECTOR_FUNCTIONS_H_ */
diff --git a/src/vm/vector_functions.hpp b/src/vm/vector_functions.hpp
index d6c496c..e196989 100644
--- a/src/vm/vector_functions.hpp
+++ b/src/vm/vector_functions.hpp
@@ -606,15 +606,15 @@ template <typename T> T roundoff(T v, uint64_t d, int64_t vxrm) {
     unsigned r = get_rounding_increment(v, d, vxrm);
     return (v >> d) + r;
 }
-template <typename dest_elem_t, typename src_elem_t = dest_elem_t>
-std::function<bool(uint64_t, vtype_t, dest_elem_t&, src_elem_t, src_elem_t)> get_sat_funct(unsigned funct6, unsigned funct3) {
+template <typename dest_elem_t, typename src2_elem_t = dest_elem_t, typename src1_elem_T = dest_elem_t>
+std::function<bool(uint64_t, vtype_t, dest_elem_t&, src2_elem_t, src1_elem_T)> get_sat_funct(unsigned funct6, unsigned funct3) {
     if(funct3 == OPIVV || funct3 == OPIVX || funct3 == OPIVI)
         switch(funct6) {
         case 0b100000: // VSADDU
-            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src_elem_t vs2, src_elem_t vs1) {
-                auto res = static_cast<twice_t<src_elem_t>>(vs2) + static_cast<twice_t<src_elem_t>>(vs1);
-                if(res > std::numeric_limits<src_elem_t>::max()) {
-                    vd = std::numeric_limits<src_elem_t>::max();
+            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src2_elem_t vs2, src1_elem_T vs1) {
+                auto res = static_cast<twice_t<src1_elem_T>>(vs2) + static_cast<twice_t<src1_elem_T>>(vs1);
+                if(res > std::numeric_limits<dest_elem_t>::max()) {
+                    vd = std::numeric_limits<dest_elem_t>::max();
                     return 1;
                 } else {
                     vd = res;
@@ -622,14 +622,14 @@ std::function<bool(uint64_t, vtype_t, dest_elem_t&, src_elem_t, src_elem_t)> get
                 }
             };
         case 0b100001: // VSADD
-            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src_elem_t vs2, src_elem_t vs1) {
-                auto res = static_cast<twice_t<std::make_signed_t<src_elem_t>>>(static_cast<std::make_signed_t<src_elem_t>>(vs2)) +
-                           static_cast<twice_t<std::make_signed_t<src_elem_t>>>(static_cast<std::make_signed_t<src_elem_t>>(vs1));
-                if(res < std::numeric_limits<std::make_signed_t<src_elem_t>>::min()) {
-                    vd = std::numeric_limits<std::make_signed_t<src_elem_t>>::min();
+            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src2_elem_t vs2, src1_elem_T vs1) {
+                auto res = static_cast<twice_t<std::make_signed_t<src2_elem_t>>>(static_cast<std::make_signed_t<src2_elem_t>>(vs2)) +
+                           static_cast<twice_t<std::make_signed_t<src1_elem_T>>>(static_cast<std::make_signed_t<src1_elem_T>>(vs1));
+                if(res < std::numeric_limits<std::make_signed_t<dest_elem_t>>::min()) {
+                    vd = std::numeric_limits<std::make_signed_t<dest_elem_t>>::min();
                     return 1;
-                } else if(res > std::numeric_limits<std::make_signed_t<src_elem_t>>::max()) {
-                    vd = std::numeric_limits<std::make_signed_t<src_elem_t>>::max();
+                } else if(res > std::numeric_limits<std::make_signed_t<dest_elem_t>>::max()) {
+                    vd = std::numeric_limits<std::make_signed_t<dest_elem_t>>::max();
                     return 1;
                 } else {
                     vd = res;
@@ -637,7 +637,7 @@ std::function<bool(uint64_t, vtype_t, dest_elem_t&, src_elem_t, src_elem_t)> get
                 }
             };
         case 0b100010: // VSSUBU
-            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src_elem_t vs2, src_elem_t vs1) {
+            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src2_elem_t vs2, src1_elem_T vs1) {
                 if(vs2 < vs1) {
                     vd = 0;
                     return 1;
@@ -647,14 +647,14 @@ std::function<bool(uint64_t, vtype_t, dest_elem_t&, src_elem_t, src_elem_t)> get
                 }
             };
         case 0b100011: // VSSUB
-            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src_elem_t vs2, src_elem_t vs1) {
-                auto res = static_cast<twice_t<std::make_signed_t<src_elem_t>>>(static_cast<std::make_signed_t<src_elem_t>>(vs2)) -
-                           static_cast<twice_t<std::make_signed_t<src_elem_t>>>(static_cast<std::make_signed_t<src_elem_t>>(vs1));
-                if(res < std::numeric_limits<std::make_signed_t<src_elem_t>>::min()) {
-                    vd = std::numeric_limits<std::make_signed_t<src_elem_t>>::min();
+            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src2_elem_t vs2, src1_elem_T vs1) {
+                auto res = static_cast<twice_t<std::make_signed_t<src2_elem_t>>>(static_cast<std::make_signed_t<src2_elem_t>>(vs2)) -
+                           static_cast<twice_t<std::make_signed_t<src1_elem_T>>>(static_cast<std::make_signed_t<src1_elem_T>>(vs1));
+                if(res < std::numeric_limits<std::make_signed_t<dest_elem_t>>::min()) {
+                    vd = std::numeric_limits<std::make_signed_t<dest_elem_t>>::min();
                     return 1;
-                } else if(res > std::numeric_limits<std::make_signed_t<src_elem_t>>::max()) {
-                    vd = std::numeric_limits<std::make_signed_t<src_elem_t>>::max();
+                } else if(res > std::numeric_limits<std::make_signed_t<dest_elem_t>>::max()) {
+                    vd = std::numeric_limits<std::make_signed_t<dest_elem_t>>::max();
                     return 1;
                 } else {
                     vd = res;
@@ -662,15 +662,15 @@ std::function<bool(uint64_t, vtype_t, dest_elem_t&, src_elem_t, src_elem_t)> get
                 }
             };
         case 0b100111: // VSMUL
-            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src_elem_t vs2, src_elem_t vs1) {
-                auto big_val = static_cast<twice_t<std::make_signed_t<src_elem_t>>>(static_cast<std::make_signed_t<src_elem_t>>(vs2)) *
-                               static_cast<twice_t<std::make_signed_t<src_elem_t>>>(static_cast<std::make_signed_t<src_elem_t>>(vs1));
+            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src2_elem_t vs2, src1_elem_T vs1) {
+                auto big_val = static_cast<twice_t<std::make_signed_t<src2_elem_t>>>(static_cast<std::make_signed_t<src2_elem_t>>(vs2)) *
+                               static_cast<twice_t<std::make_signed_t<src1_elem_T>>>(static_cast<std::make_signed_t<src1_elem_T>>(vs1));
                 auto res = roundoff(big_val, vtype.sew() - 1, vxrm);
-                if(res < std::numeric_limits<std::make_signed_t<src_elem_t>>::min()) {
-                    vd = std::numeric_limits<std::make_signed_t<src_elem_t>>::min();
+                if(res < std::numeric_limits<std::make_signed_t<dest_elem_t>>::min()) {
+                    vd = std::numeric_limits<std::make_signed_t<dest_elem_t>>::min();
                     return 1;
-                } else if(res > std::numeric_limits<std::make_signed_t<src_elem_t>>::max()) {
-                    vd = std::numeric_limits<std::make_signed_t<src_elem_t>>::max();
+                } else if(res > std::numeric_limits<std::make_signed_t<dest_elem_t>>::max()) {
+                    vd = std::numeric_limits<std::make_signed_t<dest_elem_t>>::max();
                     return 1;
                 } else {
                     vd = res;
@@ -678,45 +678,68 @@ std::function<bool(uint64_t, vtype_t, dest_elem_t&, src_elem_t, src_elem_t)> get
                 }
             };
         case 0b101010: // VSSRL
-            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src_elem_t vs2, src_elem_t vs1) {
-                vd = roundoff(vs2, vs1 & shift_mask<src_elem_t>(), vxrm);
+            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src2_elem_t vs2, src1_elem_T vs1) {
+                vd = roundoff(vs2, vs1 & shift_mask<src1_elem_T>(), vxrm);
                 return 0;
             };
         case 0b101011: // VSSRA
-            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src_elem_t vs2, src_elem_t vs1) {
-                vd = roundoff(static_cast<std::make_signed_t<src_elem_t>>(vs2), vs1 & shift_mask<src_elem_t>(), vxrm);
+            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src2_elem_t vs2, src1_elem_T vs1) {
+                vd = roundoff(static_cast<std::make_signed_t<src2_elem_t>>(vs2), vs1 & shift_mask<src1_elem_T>(), vxrm);
                 return 0;
             };
-        // case 0b101110: // VNCLIPU
-        // case 0b101111: // VNCLIP
+        case 0b101110: // VNCLIPU
+            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src2_elem_t vs2, src1_elem_T vs1) {
+                auto res = roundoff(vs2, vs1 & shift_mask<src2_elem_t>(), vxrm);
+                if(res > std::numeric_limits<dest_elem_t>::max()) {
+                    vd = std::numeric_limits<dest_elem_t>::max();
+                    return 1;
+                } else {
+                    vd = res;
+                    return 0;
+                }
+            };
+        case 0b101111: // VNCLIP
+            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src2_elem_t vs2, src1_elem_T vs1) {
+                auto res = roundoff(static_cast<std::make_signed_t<src2_elem_t>>(vs2), vs1 & shift_mask<src2_elem_t>(), vxrm);
+                if(res < std::numeric_limits<std::make_signed_t<dest_elem_t>>::min()) {
+                    vd = std::numeric_limits<std::make_signed_t<dest_elem_t>>::min();
+                    return 1;
+                } else if(res > std::numeric_limits<std::make_signed_t<dest_elem_t>>::max()) {
+                    vd = std::numeric_limits<std::make_signed_t<dest_elem_t>>::max();
+                    return 1;
+                } else {
+                    vd = res;
+                    return 0;
+                }
+            };
         default:
             throw new std::runtime_error("Unknown funct6 in get_sat_funct");
         }
     else if(funct3 == OPMVV || funct3 == OPMVX)
         switch(funct6) {
         case 0b001000: // VAADDU
-            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src_elem_t vs2, src_elem_t vs1) {
-                auto res = static_cast<twice_t<src_elem_t>>(vs2) + static_cast<twice_t<src_elem_t>>(vs1);
+            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src2_elem_t vs2, src1_elem_T vs1) {
+                auto res = static_cast<twice_t<src2_elem_t>>(vs2) + static_cast<twice_t<src1_elem_T>>(vs1);
                 vd = roundoff(res, 1, vxrm);
                 return 0;
             };
         case 0b001001: // VAADD
-            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src_elem_t vs2, src_elem_t vs1) {
-                auto res = static_cast<twice_t<std::make_signed_t<src_elem_t>>>(static_cast<std::make_signed_t<src_elem_t>>(vs2)) +
-                           static_cast<twice_t<std::make_signed_t<src_elem_t>>>(static_cast<std::make_signed_t<src_elem_t>>(vs1));
+            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src2_elem_t vs2, src1_elem_T vs1) {
+                auto res = static_cast<twice_t<std::make_signed_t<src2_elem_t>>>(static_cast<std::make_signed_t<src2_elem_t>>(vs2)) +
+                           static_cast<twice_t<std::make_signed_t<src1_elem_T>>>(static_cast<std::make_signed_t<src1_elem_T>>(vs1));
                 vd = roundoff(res, 1, vxrm);
                 return 0;
             };
         case 0b001010: // VASUBU
-            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src_elem_t vs2, src_elem_t vs1) {
-                auto res = static_cast<twice_t<src_elem_t>>(vs2) - static_cast<twice_t<src_elem_t>>(vs1);
+            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src2_elem_t vs2, src1_elem_T vs1) {
+                auto res = static_cast<twice_t<src2_elem_t>>(vs2) - static_cast<twice_t<src1_elem_T>>(vs1);
                 vd = roundoff(res, 1, vxrm);
                 return 0;
             };
         case 0b001011: // VASUB
-            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src_elem_t vs2, src_elem_t vs1) {
-                auto res = static_cast<twice_t<std::make_signed_t<src_elem_t>>>(static_cast<std::make_signed_t<src_elem_t>>(vs2)) -
-                           static_cast<twice_t<std::make_signed_t<src_elem_t>>>(static_cast<std::make_signed_t<src_elem_t>>(vs1));
+            return [](uint64_t vxrm, vtype_t vtype, dest_elem_t& vd, src2_elem_t vs2, src1_elem_T vs1) {
+                auto res = static_cast<twice_t<std::make_signed_t<src2_elem_t>>>(static_cast<std::make_signed_t<src2_elem_t>>(vs2)) -
+                           static_cast<twice_t<std::make_signed_t<src1_elem_T>>>(static_cast<std::make_signed_t<src1_elem_T>>(vs1));
                 vd = roundoff(res, 1, vxrm);
                 return 0;
             };
@@ -726,16 +749,16 @@ std::function<bool(uint64_t, vtype_t, dest_elem_t&, src_elem_t, src_elem_t)> get
     else
         throw new std::runtime_error("Unknown funct3 in get_sat_funct");
 }
-template <unsigned VLEN, typename dest_elem_t, typename src_elem_t>
+template <unsigned VLEN, typename dest_elem_t, typename src2_elem_t, typename src1_elem_T>
 bool sat_vector_vector_op(uint8_t* V, unsigned funct6, unsigned funct3, uint64_t vl, uint64_t vstart, vtype_t vtype, int64_t vxrm, bool vm,
                           unsigned vd, unsigned vs2, unsigned vs1) {
     uint64_t elem_count = VLEN * vtype.lmul() / vtype.sew();
     bool saturated = false;
     vmask_view mask_reg = read_vmask<VLEN>(V, elem_count);
-    auto vs1_view = get_vreg<VLEN, src_elem_t>(V, vs1, elem_count);
-    auto vs2_view = get_vreg<VLEN, src_elem_t>(V, vs2, elem_count);
+    auto vs1_view = get_vreg<VLEN, src1_elem_T>(V, vs1, elem_count);
+    auto vs2_view = get_vreg<VLEN, src2_elem_t>(V, vs2, elem_count);
     auto vd_view = get_vreg<VLEN, dest_elem_t>(V, vd, elem_count);
-    auto fn = get_sat_funct<dest_elem_t, src_elem_t>(funct6, funct3);
+    auto fn = get_sat_funct<dest_elem_t, src2_elem_t, src1_elem_T>(funct6, funct3);
     // elements w/ index smaller than vstart are in the prestart and get skipped
     // body is from vstart to min(elem_count, vl)
     for(unsigned idx = vstart; idx < std::min(elem_count, vl); idx++) {
@@ -754,15 +777,15 @@ bool sat_vector_vector_op(uint8_t* V, unsigned funct6, unsigned funct3, uint64_t
     }
     return saturated;
 }
-template <unsigned VLEN, typename dest_elem_t, typename src_elem_t>
+template <unsigned VLEN, typename dest_elem_t, typename src2_elem_t, typename src1_elem_T>
 bool sat_vector_imm_op(uint8_t* V, unsigned funct6, unsigned funct3, uint64_t vl, uint64_t vstart, vtype_t vtype, int64_t vxrm, bool vm,
-                       unsigned vd, unsigned vs2, typename std::make_signed<src_elem_t>::type imm) {
+                       unsigned vd, unsigned vs2, typename std::make_signed<src1_elem_T>::type imm) {
     uint64_t elem_count = VLEN * vtype.lmul() / vtype.sew();
     bool saturated = false;
     vmask_view mask_reg = read_vmask<VLEN>(V, elem_count);
-    auto vs2_view = get_vreg<VLEN, src_elem_t>(V, vs2, elem_count);
+    auto vs2_view = get_vreg<VLEN, src2_elem_t>(V, vs2, elem_count);
     auto vd_view = get_vreg<VLEN, dest_elem_t>(V, vd, elem_count);
-    auto fn = get_sat_funct<dest_elem_t, src_elem_t>(funct6, funct3);
+    auto fn = get_sat_funct<dest_elem_t, src2_elem_t, src1_elem_T>(funct6, funct3);
     // elements w/ index smaller than vstart are in the prestart and get skipped
     // body is from vstart to min(elem_count, vl)
     for(unsigned idx = vstart; idx < std::min(elem_count, vl); idx++) {