Merge branch 'cachesim' of https://github.com/AlecVercruysse/cvw into cachesim

examples/fp/softfloat_demo/softfloat_demo2.c

@@ -0,0 +1,77 @@
+//
+// softfloat_div.c
+// james.stine@okstate.edu 12 April 2023
+// 
+// Demonstrate using SoftFloat to compute 754 fp divide, then print results
+// (adapted from original C built by David Harris)
+//
+
+#include <stdio.h>
+#include <stdint.h>
+#include "softfloat.h"
+#include "softfloat_types.h"
+typedef union sp {
+  uint32_t v;
+  unsigned short x[2];
+  float f;
+} sp;
+
+void printF32 (char *msg, float32_t f) {
+  sp conv;
+  int i, j;
+  conv.v = f.v; // use union to convert between hexadecimal and floating-point views
+  printf("%s: ", msg);  // print out nicely
+  printf("0x%04x_%04x = %1.15g\n", (conv.v >> 16),(conv.v & 0xFFFF), conv.f);
+}
+
+void printFlags(void) {
+  int NX = softfloat_exceptionFlags % 2;
+  int UF = (softfloat_exceptionFlags >> 1) % 2;
+  int OF = (softfloat_exceptionFlags >> 2) % 2;
+  int DZ = (softfloat_exceptionFlags >> 3) % 2;
+  int NV = (softfloat_exceptionFlags >> 4) % 2;
+  printf ("Flags: Inexact %d Underflow %d Overflow %d DivideZero %d Invalid %d\n", 
+          NX, UF, OF, DZ, NV);
+}
+
+void softfloatInit(void) {
+    // RNE: softfloat_round_near_even
+    // RZ:  softfloat_round_minMag
+    // RU:  softfloat_round_max
+    // RD:  softfloat_round_min
+    // RM: softfloat_round_near_maxMag   
+    softfloat_roundingMode = softfloat_round_near_even; 
+    softfloat_exceptionFlags = 0; // clear exceptions
+    softfloat_detectTininess = softfloat_tininess_afterRounding; // RISC-V behavior for tininess
+}
+
+int main() {
+
+  // float32_t is typedef in SoftFloat
+  float32_t x, y, r1, r2;
+  sp convx, convy;
+
+  // Choose two random values
+  convx.f = 1.30308703073;
+  convy.f = 1.903038030370;
+  // Convert to SoftFloat format
+  x.v = (convx.x[1] << 16) + convx.x[0];
+  y.v = (convy.x[1] << 16) + convy.x[0];  
+
+  printf("Example using SoftFloat\n");
+  
+  softfloatInit();
+  r1 = f32_div(x, y);
+  printf("-------\n");
+  printF32("X", x);
+  printF32("Y", y); 
+  printF32("result = X/Y", r1);
+  printFlags();
+
+  r2 = f32_sqrt(x);
+  printf("-------\n");    
+  printF32("X", x);
+  printF32("result = sqrt(X)", r2);
+  printFlags();  
+
+}

sim/testfloat.do

@@ -29,20 +29,18 @@ vlog +incdir+../config/$1 +incdir+../config/shared ../testbench/testbench-fp.sv
 
 vsim -voptargs=+acc work.testbenchfp -G TEST=$2
 
-#-- display input and output signals as hexidecimal values
-if {$3 == "wave"} {
+# Determine if nowave argument is provided
+#   this removes any output to a wlf or wave window to reduce
+#   disk space.
+if {($argc > 2) && ($3 eq "nowave")} {
+    puts "No wave output is selected"
+} else {
     puts "wave output is selected"
     view wave
     add log -recursive /*
     do wave-fpu.do    
-} elseif {$3 == "nowave"} {
-    puts "No wave output is selected"
-} else {
-    puts "Error with third argument"
-    exit 2
 }  
 
-
 #-- Run the Simulation 
 run -all
 noview testbench-fp.sv

tests/coverage/WALLY-init-lib.h

@@ -66,8 +66,7 @@ interrupt:              # must be a timer interrupt
     j trap_return       # clean up and return
 
 exception:
-    li t0, 2
-    csrr t1, mcause
+    csrr t0, mcause
     li t1, 8            # is it an ecall trap?
     andi t0, t0, 0xFC # if CAUSE = 8, 9, or 11
     bne t0, t1, trap_return # ignore other exceptions

tests/coverage/fpu.S

@@ -31,6 +31,11 @@ main:
     #bseti t0, zero, 14  # turn on FPU
     csrs mstatus, t0
 
+    #Pull denormalized FP number from memory and pass it to fclass.S for coverage
+    la t0, TestData
+    flw ft0, 0(t0)
+    fclass.s t1, ft0
+
     # Test legal instructions not covered elsewhere
     flq ft0, 0(a0)
     flh ft0, 8(a0)
@@ -98,3 +103,7 @@ main:
 
     j done
 
+.section .data
+.align 3
+TestData:
+.int 0x00100000 #Denormalized FP number