freedreno/computer: add script to test widening/narrowing

Just something I hacked together to help figure out which instructions
can fold in a wideing/narrowing conversion.

Signed-off-by: Rob Clark <robdclark@chromium.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4780>

diff --git a/src/freedreno/computerator/examples/test-opcodes.sh b/src/freedreno/computerator/examples/test-opcodes.sh
new file mode 100755 (executable)
index 0000000..e6f7e73
--- /dev/null
+++ b/src/freedreno/computerator/examples/test-opcodes.sh
@@ -0,0 +1,297 @@
+#!/bin/bash
+#
+# Test various instructions to check whether half<->full widening/narrowing
+# works.  The basic premise is to perform the same instruction with and
+# without the widening/narrowing folded in and check if the results match.
+#
+# Note this doesn't currently diferentiate between signed/unsigned/bool,
+# and just assumes int is signed (since unsigned is basically(ish) like
+# signed but without sign extension)
+#
+# TODO probably good pick numeric src values that are better at triggering
+# edge cases, while still not loosing precision in a full->half->full
+# seqeuence.. but some instructions like absneg don't even appear to be
+# subtlely wrong when you try to fold in a precision conversion.
+#
+# add '-v' arg to see the result values
+
+set -e
+
+#
+# Templates for float->float instructions:
+#
+f2f_instrs=(
+       'add.f $dst, $src1, $src2'
+       'min.f $dst, $src1, $src2'
+       'min.f $dst, $src2, $src1'
+       'max.f $dst, $src1, $src2'
+       'max.f $dst, $src2, $src1'
+       'mul.f $dst, $src1, $src2'
+       'sign.f $dst, $src1'
+       'absneg.f $dst, \(neg\)$src1'
+       'absneg.f $dst, \(abs\)$src1'
+       'floor.f $dst, $src1'
+       'ceil.f $dst, $src1'
+       'rndne.f $dst, $src1'
+       'rndaz.f $dst, $src1'
+       'trunc.f $dst, $src1'
+)
+
+#
+# Templates for float->int instructions:
+#
+f2i_instrs=(
+       'cmps.f.gt $dst, $src1, $src2'
+       'cmps.f.lt $dst, $src1, $src2'
+       'cmpv.f.gt $dst, $src1, $src2'
+       'cmpv.f.lt $dst, $src1, $src2'
+)
+
+#
+# Templates for int->int instructions:
+#
+i2i_instrs=(
+       'add.u $dst, $src1, $src2'
+       'add.s $dst, $src1, $src2'
+       'sub.u $dst, $src1, $src2'
+       'sub.s $dst, $src1, $src2'
+       'cmps.f.gt $dst, $src1, $src2'
+       'cmps.f.lt $dst, $src1, $src2'
+       'min.u $dst, $src1, $src2'
+       'min.u $dst, $src2, $src1'
+       'min.s $dst, $src1, $src2'
+       'min.s $dst, $src2, $src1'
+       'max.u $dst, $src1, $src2'
+       'max.u $dst, $src2, $src1'
+       'max.s $dst, $src1, $src2'
+       'max.s $dst, $src2, $src1'
+       'absneg.s $dst, \(neg\)$src1'
+       'absneg.s $dst, \(abs\)$src1'
+       'and.b $dst, $src2, $src3'
+       'or.b $dst, $src1, $src2'
+       'not.b $dst, $src1'
+       'xor.b $dst, $src1, $src2'
+       'cmpv.u.gt $dst, $src1, $src2'
+       'cmpv.u.lt $dst, $src1, $src2'
+       'cmpv.s.gt $dst, $src1, $src2'
+       'cmpv.s.lt $dst, $src1, $src2'
+       'mul.u24 $dst, $src1, $src2'
+       'mul.s24 $dst, $src1, $src2'
+       'mull.u $dst, $src1, $src2'
+       'bfrev.b $dst, $src1'
+       'clz.s $dst, $src2'
+       'clz.b $dst, $src2'
+       'shl.b $dst, $src1, $src2'
+       'shr.b $dst, $src3, $src1'
+       'ashr.b $dst, $src3, $src1'
+       'mgen.b $dst, $src1, $src2'
+       'getbit.b $dst, $src3, $src2'
+       'setrm $dst, $src1'
+       'cbits.b $dst, $src3'
+       'shb $dst, $src1, $src2'
+       'msad $dst, $src1, $src2'
+)
+
+#
+# Helper to expand instruction template:
+#
+expand() {
+       instr=$1
+       dst=$2
+       src1=$3
+       src2=$4
+       src3=$5
+       eval echo $instr
+}
+
+expand_test() {
+       instr=$1
+
+       echo '; control, half->half:'
+       expand $instr "hr1.x" "hr0.x" "hr0.y" "hr0.z"
+       echo '; test, full->half:'
+       expand $instr "hr1.y" "r1.x" "r1.y" "r1.z"
+
+       echo '; control, full->full:'
+       expand $instr "r2.x" "r1.x" "r1.y" "r1.z"
+       echo '; test, half->full:'
+       expand $instr "r2.y" "hr0.x" "hr0.y" "hr0.z"
+
+       echo "(rpt5)nop"
+}
+
+#
+# Helpers to construct test program assembly:
+#
+header_asm() {
+       cat <<EOF
+@localsize 1, 1, 1
+@buf 4  ; g[0]
+EOF
+}
+
+footer_asm() {
+       cat <<EOF
+; dest offsets:
+mov.u32u32 r3.x, 0
+mov.u32u32 r3.y, 1
+mov.u32u32 r3.z, 2
+mov.u32u32 r3.w, 3
+(rpt5)nop
+
+; and store results:
+stib.untyped.1d.u32.1 g[0] + r3.x, r2.x   ; control: full->full
+stib.untyped.1d.u32.1 g[0] + r3.y, r2.y   ; test:    half->full
+stib.untyped.1d.u32.1 g[0] + r3.z, r2.z   ; control: half->half
+stib.untyped.1d.u32.1 g[0] + r3.w, r2.w   ; test:    full->half
+(sy)nop
+end
+EOF
+}
+
+setup_asm_float() {
+       cat <<EOF
+; hr0->hr1 (r0) avail for half, hr0 for src, hr1 for dst
+; r1->r2 avail for full, r1 for src, r2 for dst
+cov.f32f16 hr0.x, (1.0)
+cov.f32f16 hr0.y, (2.0)
+cov.f32f16 hr0.z, (3.0)
+mov.f32f32 r1.x,  (1.0)
+mov.f32f32 r1.y,  (2.0)
+mov.f32f32 r1.z,  (3.0)
+(rpt5)nop
+EOF
+}
+
+setup_asm_int() {
+       cat <<EOF
+; hr0->hr1 (r0) avail for half, hr0 for src, hr1 for dst
+; r1->r2 avail for full, r1 for src, r2 for dst
+cov.s32s16 hr0.x,  1
+cov.s32s16 hr0.y, -2
+cov.s32s16 hr0.z,  3
+mov.s32s32 r1.x,   1
+mov.s32s32 r1.y,  -2
+mov.s32s32 r1.z,   3
+(rpt5)nop
+EOF
+}
+
+#
+# Generate assembly code to test float->float opcode
+#
+f2f_asm() {
+       instr=$1
+
+       header_asm
+       setup_asm_float
+       expand_test $instr
+
+       cat <<EOF
+; convert half results back to full:
+cov.f16f32 r2.z, hr1.x
+cov.f16f32 r2.w, hr1.y
+EOF
+
+       footer_asm
+}
+
+#
+# Generate assembly code to test float->int opcode
+#
+f2i_asm() {
+       instr=$1
+
+       header_asm
+       setup_asm_float
+       expand_test $instr
+
+       cat <<EOF
+; convert half results back to full:
+cov.s16s32 r2.z, hr1.x
+cov.s16s32 r2.w, hr1.y
+EOF
+
+       footer_asm
+}
+
+#
+# Generate assembly code to test int->int opcode
+#
+i2i_asm() {
+       instr=$1
+
+       header_asm
+       setup_asm_int
+       expand_test $instr
+
+       cat <<EOF
+; convert half results back to full:
+cov.s16s32 r2.z, hr1.x
+cov.s16s32 r2.w, hr1.y
+EOF
+
+       footer_asm
+}
+
+
+#
+# Helper to parse computerator output and print results:
+#
+check_results() {
+       str=`cat - | grep "     " | head -1 | xargs`
+
+       if [ "$verbose" = "true" ]; then
+               echo $str
+       fi
+
+       # Split components of result buffer:
+       cf=$(echo $str | cut -f1 -d' ')
+       tf=$(echo $str | cut -f2 -d' ')
+       ch=$(echo $str | cut -f3 -d' ')
+       th=$(echo $str | cut -f4 -d' ')
+
+       # Sanity test, make sure the control results match:
+       if [ $cf != $ch ]; then
+               echo "    FAIL: control results do not match!  Half vs full op is not equivalent!"
+               echo "    full=$cf half=$ch"
+       fi
+
+       # Compare test (with conversion folded) to control:
+       if [ $cf != $tf ]; then
+               echo "    FAIL: half -> full widening result does not match control!"
+               echo "    control=$cf result=$tf"
+       fi
+       if [ $ch != $th ]; then
+               echo "    FAIL: full -> half narrowing result does not match control!"
+               echo "    control=$ch result=$th"
+       fi
+
+       # HACK without a delay different invocations
+       # of computerator seem to somehow clobber each
+       # other.. which isn't great..
+       sleep 0.1
+}
+
+#
+# Run the tests!
+#
+
+if [ "$1" = "-v" ]; then
+       verbose="true"
+fi
+
+IFS=""
+for instr in ${f2f_instrs[@]}; do
+       echo "TEST: $instr"
+       f2f_asm $instr | ./computerator -g 1,1,1 | check_results
+done
+for instr in ${f2i_instrs[@]}; do
+       echo "TEST: $instr"
+       f2i_asm $instr | ./computerator -g 1,1,1 | check_results
+done
+for instr in ${i2i_instrs[@]}; do
+       echo "TEST: $instr"
+       i2i_asm $instr | ./computerator -g 1,1,1 | check_results
+done
+