Fix bug where the condition check of the ?: operator may be mis-evaluated.

This could happen in certain cases where the condition codes might not be set at expected. The following program gives an example:

#pragma optimize 1
#include <stdio.h>
int one(void) {return 1;}
int negative_one(void) {return -1;}
int main(void) {
    puts((one() + negative_one()) ? "A" : "B");
}

This could also occur if the condition used the % operator, particularly after the recent changes to it.

Also, add unsigned multiplication, division, and modulo operations to the list of those that may not set the condition codes based on the result value, both in this and other contexts.

Detected based on several programs from FizzBuzz-C.

Gen.pas

@@ -404,7 +404,8 @@ begin {NeedsCondition}
 NeedsCondition := opcode in
    [pc_and,pc_ior,pc_cui,pc_cup,pc_lor,pc_lnd,pc_ldl,pc_lil,pc_lld,
     pc_lli,pc_gil,pc_gli,pc_gdl,pc_gld,pc_iil,pc_ili,pc_idl,pc_ild,
-    pc_cop,pc_cpo,pc_cpi,pc_dvi,pc_mpi,pc_adi,pc_sbi,pc_mod,pc_bno];
+    pc_cop,pc_cpo,pc_cpi,pc_dvi,pc_mpi,pc_adi,pc_sbi,pc_mod,pc_bno,
+    pc_udi,pc_uim,pc_umi];
 end; {NeedsCondition}
 
 
@@ -5448,9 +5449,7 @@ procedure GenTree {op: icptr};
    lab2 := GenLabel;
    lab3 := GenLabel;
    GenTree(op^.left);
-   if op^.left^.opcode in
-      [pc_and,pc_ior,pc_cui,pc_cup,pc_lor,pc_lnd,pc_ldl,pc_lil,pc_lld,
-       pc_lli,pc_gil,pc_gli,pc_gdl,pc_gld] then
+   if NeedsCondition(op^.left^.opcode) then
       GenImplied(m_tax);
    GenNative(m_beq, relative, lab1, nil, 0);
    GenNative(m_brl, longrelative, lab2, nil, 0);