Arithmetic exception flag and a plethora of tests.

doc/gmqcc.1

@@ -581,6 +581,11 @@ breaks decompilers, but causes the output file to be better compressible.
 In commutative instructions, always put the lower-numbered operand first.
 This shaves off 1 byte of entropy from all these instructions, reducing
 compressed size of the output file.
+.It Fl f Ns Cm arithmetic-exceptions
+Turn on arithmetic exception tests in the compiler. In constant expressions
+which trigger exceptions like division by zero, overflow, underflow, etc,
+the following flag will produce diagnostics for what triggered that
+exception.
 .El
 .Sh OPTIMIZATIONS
 .Bl -tag -width Ds

fold.c

@@ -820,6 +820,9 @@ static bool fold_check_except_float(sfloat_t (*callback)(sfloat_state_t *, sfloa
     sfloat_cast_t ca;
     sfloat_cast_t cb;
 
+    if (!OPTS_FLAG(ARITHMETIC_EXCEPTIONS))
+        return false;
+
     s.roundingmode   = SFLOAT_ROUND_NEAREST_EVEN;
     s.tiny           = SFLOAT_TBEFORE;
     s.exceptionflags = 0;

gmqcc.ini.example

@@ -310,6 +310,11 @@
     SORT_OPERANDS = false
 
 
+    #Turn on arithmetic exception tests in the compiler. In constant expressions
+    #which trigger exceptions like division by zero, overflow, underflow, etc,
+    #the following flag will produce diagnostics for what triggered that
+    #exception.
+    ARITHMETIC_EXCEPTIONS = false
 
 [warnings]
     #Generate a warning about variables which are declared but never

opts.def

@@ -56,6 +56,7 @@
     GMQCC_DEFINE_FLAG(UNSAFE_VARARGS)
     GMQCC_DEFINE_FLAG(TYPELESS_STORES)
     GMQCC_DEFINE_FLAG(SORT_OPERANDS)
+    GMQCC_DEFINE_FLAG(ARITHMETIC_EXCEPTIONS)
 #endif
 
 /* warning flags */

tests/arithexcept.qc

@@ -0,0 +1,13 @@
+const float huge = 340282346638528859811704183484516925440; // FLT_MAX
+
+#ifdef DIVBYZERO
+const float a = 1.0 / 0.0;
+#endif
+
+#ifdef OVERFLOW
+const float a = huge * huge;
+#endif
+
+#ifdef UNDERFLOW
+const float a = 1 / huge;
+#endif

tests/arithexcept.tmpl

@@ -0,0 +1,4 @@
+I: arithexcept.qc
+D: arithmetic exceptions (divide by zero)
+T: -fail
+C: -std=fteqcc -farithmetic-exceptions -DDIVBYZERO

tests/arithexcept_of.tmpl

@@ -0,0 +1,4 @@
+I: arithexcept.qc
+D: arithmetic exceptions (overflow)
+T: -fail
+C: -std=ftqcc -farithmetic-exceptions -DOVERFLOW

tests/arithexcept_uf.tmpl

@@ -0,0 +1,4 @@
+I: arithexcept.qc
+D: arithmetic exceptions (underflow)
+T: -fail
+C: -std=ftqcc -farithmetic-exceptions -DUNDERFLOW

tests/inexact.qc

@@ -0,0 +1,8 @@
+void main() {
+    const float a = 1.0 / 3.0;
+    const float b = 0.3333333333333;
+
+    if (a == b) {
+        // Should trigger warning
+    }
+}

tests/inexact.tmpl

@@ -0,0 +1,4 @@
+I: inexact.qc
+D: inexact comparisons
+T: -fail
+C: -std=gmqcc -Winexact-compares -Wall -Werror