PR target 78658 exposed a thinko that I had in extending the conversion of
QImode and HImode to floating point. If the QImode/HImode value was in a
vector register, the pattern didn't allocate the second pseudo register, but
the code generated a reference to that second register. The second register
was used to move the value from a GPR to the vector registers.
I also modified the zero extend patterns to use ^ instead of ?* like I did on
the November 21st patches so that the register allocator is more likely to
consider using the vector registers if it is useful to do so.
I have done a bootstrap build and make check on a little endian power8 system
and there were no regressions. Can I check this into the trunk?
[gcc]
2016-12-06 Michael Meissner <[email protected]>
PR target/78658
* config/rs6000/rs6000.md (zero_extendqi<mode>2): Use ^ instead of
?* constraints for the ISA 3.0 patterns, so the register allocator
is more likely to allocate QImode/HImode to vector registers for
conversion to floating point point unless a reload is needed.
(zero_extendhi<mode>2): Likewise.
(float<QHI:mode><FP_ISA3:mode>2_internal): Properly deal with the
first alternative which is converting QImode/HImode to floating
point and the QImode/HImode value is in a vector register, and
does not allocate the second temorary.
(floatuns<QHI:mode><FP_ISA3:mode>2_internal): Likewise.
[gcc/testsuite]
2016-12-06 Michael Meissner <[email protected]>
PR target/78658
* gcc.target/powerpc/pr78658.c: New test.
--
Michael Meissner, IBM
IBM, M/S 2506R, 550 King Street, Littleton, MA 01460-6245, USA
email: [email protected], phone: +1 (978) 899-4797
Index: gcc/config/rs6000/rs6000.md
===================================================================
--- gcc/config/rs6000/rs6000.md (revision 243301)
+++ gcc/config/rs6000/rs6000.md (working copy)
@@ -738,8 +738,8 @@ (define_code_attr SMINMAX [(smin "SM
;; complex forms. Basic data transfer is done later.
(define_insn "zero_extendqi<mode>2"
- [(set (match_operand:EXTQI 0 "gpc_reg_operand" "=r,r,?*wJwK,?*wK")
- (zero_extend:EXTQI (match_operand:QI 1 "reg_or_mem_operand"
"m,r,Z,*wK")))]
+ [(set (match_operand:EXTQI 0 "gpc_reg_operand" "=r,r,^wJwK,^wK")
+ (zero_extend:EXTQI (match_operand:QI 1 "reg_or_mem_operand"
"m,r,Z,wK")))]
""
"@
lbz%U1%X1 %0,%1
@@ -791,7 +791,7 @@ (define_insn_and_split "*zero_extendqi<m
(define_insn "zero_extendhi<mode>2"
- [(set (match_operand:EXTHI 0 "gpc_reg_operand" "=r,r,?*wJwK,?*wK")
+ [(set (match_operand:EXTHI 0 "gpc_reg_operand" "=r,r,^wJwK,^wK")
(zero_extend:EXTHI (match_operand:HI 1 "reg_or_mem_operand"
"m,r,Z,wK")))]
""
"@
@@ -5413,8 +5413,11 @@ (define_insn_and_split "*float<QHI:mode>
if (!MEM_P (input))
{
+ rtx tmp = operands[3];
if (altivec_register_operand (input, <QHI:MODE>mode))
emit_insn (gen_extend<QHI:mode>di2 (di, input));
+ else if (GET_CODE (tmp) == SCRATCH)
+ emit_insn (gen_extend<QHI:mode>di2 (di, input));
else
{
rtx tmp = operands[3];
@@ -5449,7 +5452,7 @@ (define_expand "floatuns<QHI:mode><FP_IS
(define_insn_and_split "*floatuns<QHI:mode><FP_ISA3:mode>2_internal"
[(set (match_operand:FP_ISA3 0 "vsx_register_operand" "=<Fv>,<Fv>,<Fv>")
(unsigned_float:FP_ISA3
- (match_operand:QHI 1 "reg_or_indexed_operand" "wJwK,r,Z")))
+ (match_operand:QHI 1 "reg_or_indexed_operand" "wK,r,Z")))
(clobber (match_scratch:DI 2 "=wK,wi,wJwK"))
(clobber (match_scratch:DI 3 "=X,r,X"))]
"TARGET_P9_VECTOR && TARGET_DIRECT_MOVE && TARGET_POWERPC64
@@ -5467,8 +5470,13 @@ (define_insn_and_split "*floatuns<QHI:mo
else
{
rtx tmp = operands[3];
- emit_insn (gen_zero_extend<QHI:mode>di2 (tmp, input));
- emit_move_insn (di, tmp);
+ if (GET_CODE (tmp) == SCRATCH)
+ emit_insn (gen_extend<QHI:mode>di2 (di, input));
+ else
+ {
+ emit_insn (gen_zero_extend<QHI:mode>di2 (tmp, input));
+ emit_move_insn (di, tmp);
+ }
}
emit_insn (gen_floatdi<FP_ISA3:mode>2 (result, di));
Index: gcc/testsuite/gcc.target/powerpc/pr78658.c
===================================================================
--- gcc/testsuite/gcc.target/powerpc/pr78658.c (revision 0)
+++ gcc/testsuite/gcc.target/powerpc/pr78658.c (working copy)
@@ -0,0 +1,14 @@
+/* { dg-do compile { target { powerpc64*-*-* && lp64 } } } */
+/* { dg-skip-if "do not override -mcpu" { powerpc*-*-* } { "-mcpu=*" } {
"-mcpu=power9" } } */
+/* { dg-require-effective-target powerpc_p9vector_ok } */
+/* { dg-options "-mcpu=power9 -O2" } */
+
+/* This caused an unrecognizable insn message on development versions of GCC
7. */
+
+float a;
+char b;
+
+void c(void)
+{
+ a = b = a;
+}
