On Sat, Jan 14, 2017 at 09:19:52AM -0600, Segher Boessenkool wrote:
> On Sun, Jan 15, 2017 at 12:08:39AM +1030, Alan Modra wrote:
> > > Have you checked if/what this changes for some bigger code?
> >
> > Well, the bootstrap was all langs (minus ada due to not having ada
> > installed) and ppc32 multilibs were built. Plus the testsuite run
> > with RUNTESTFLAGS="--target_board=unix'{-m32,-m64}{-mlra,-mno-lra}'"
> >
> > I would have bootstrapped -m32 except the machine I used lacked 32-bit
> > gmp, mpfr, mpc and I was lazy.
> >
> > > Okay for trunk if there is nothing unexpected. Thanks!
> >
> > I guess I should at least build glibc.
>
> Yes exactly, something big that uses pic -- it is pretty obvious it won't
> change anything for non-pic.
glibc built fine without elf_high/elf_low with no regressions in its
testsuite. However, there is a problem in rs6000_emit_allocate_stack
-fstack-limit-symbol=SYMBOL code. This now might ICE if someone tries
to use the option with -fpic/PIC. I reckon the option combination to
be little used, so it shouldn't hurt to disable -fstack-limit-symbol
for PIC. (We were generating non-PIC for the trap, so we probably
would have gotten a complaint about text relocs in shared libraries.)
This revised patch has been bootstrapped and regression tested as
before, and tested with glibc too. OK?
PR target/79066
* config/rs6000/rs6000.md (elf_high, elf_low): Disable when pic.
* config/rs6000/rs6000.c (rs6000_emit_allocate_stack): Don't allow
symbolic stack limit when pic.
testsuite/
* gcc.target/powerpc/pr79066.c: New.
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 11394b2..2dd6bbe 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -27668,7 +27668,8 @@ rs6000_emit_allocate_stack (HOST_WIDE_INT size, rtx
copy_reg, int copy_off)
}
else if (GET_CODE (stack_limit_rtx) == SYMBOL_REF
&& TARGET_32BIT
- && DEFAULT_ABI == ABI_V4)
+ && DEFAULT_ABI == ABI_V4
+ && !flag_pic)
{
rtx toload = gen_rtx_CONST (VOIDmode,
gen_rtx_PLUS (Pmode,
diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md
index b333474..f00334a 100644
--- a/gcc/config/rs6000/rs6000.md
+++ b/gcc/config/rs6000/rs6000.md
@@ -10581,14 +10581,14 @@ (define_insn_and_split "*tocref<mode>"
(define_insn "elf_high"
[(set (match_operand:SI 0 "gpc_reg_operand" "=b*r")
(high:SI (match_operand 1 "" "")))]
- "TARGET_ELF && ! TARGET_64BIT"
+ "TARGET_ELF && !TARGET_64BIT && !flag_pic"
"lis %0,%1@ha")
(define_insn "elf_low"
[(set (match_operand:SI 0 "gpc_reg_operand" "=r")
(lo_sum:SI (match_operand:SI 1 "gpc_reg_operand" "b")
(match_operand 2 "" "")))]
- "TARGET_ELF && ! TARGET_64BIT"
+ "TARGET_ELF && !TARGET_64BIT && !flag_pic"
"la %0,%2@l(%1)")
;; Call and call_value insns
diff --git a/gcc/testsuite/gcc.target/powerpc/pr79066.c
b/gcc/testsuite/gcc.target/powerpc/pr79066.c
new file mode 100644
index 0000000..86b2014
--- /dev/null
+++ b/gcc/testsuite/gcc.target/powerpc/pr79066.c
@@ -0,0 +1,14 @@
+/* { dg-do compile { target { fpic && ilp32 } } } */
+/* { dg-options "-O2 -fpic" } */
+/* { dg-final { scan-assembler-not "lis.*@ha" } } */
+
+union U { double x; int i[2]; };
+
+double
+foo (double x)
+{
+ union U v;
+ v.i[0] = 0x7ff00000;
+ v.i[1] = 0;
+ return x / v.x;
+}
--
Alan Modra
Australia Development Lab, IBM
