I see that David already proposed this same patch in PR83946. Sorry, I've
gotten behind on my email.
Two changes I need: The scan-assembly should have \$ rather than $ in it, and
I should add
PR83946 to the ChangeLog.
Sorry for the noise.
-- Bill
Bill Schmidt, Ph.D.
STSM, GCC Architect for Linux on POWER
Linux on Power Toolchain
IBM Linux Technology Center
wschm...@linux.vnet.ibm.com
> On Jan 19, 2018, at 2:58 PM, Bill Schmidt <wschm...@linux.vnet.ibm.com> wrote:
>
> Hi,
>
> My recent patches to trunk and gcc-7-branch for avoiding speculation of
> indirect branches has a flaw, pointed out by David. Usage of "." to
> represent the program counter is not portable across all POWER
> assemblers, particularly not being accepted on AIX. "$" is the
> universally accepted alternative. So change the code and the test
> cases to use $ instead of . for this purpose.
>
> Regstrap is in progress on powerpc64-linux-gnu and powerpc64le-linux-gnu.
> Assuming no issues are found, is this okay for trunk and backport to 7?
>
> Thanks,
> Bill
>
>
> [gcc]
>
> 2018-01-19 Bill Schmidt <wschm...@linux.vnet.ibm.com>
>
> * config/rs6000/rs6000.md (*sibcall_nonlocal_sysv<mode>): Change
> assembly output from . to $.
> (*sibcall_value_nonlocal_sysv<mode>): Likewise.
> (indirect_jump<mode>_nospec): Likewise.
> (*tablejump<mode>_internal1_nospec): Likewise.
>
> [gcc/testsuite]
>
> 2018-01-19 Bill Schmidt <wschm...@linux.vnet.ibm.com>
>
> * gcc.target/powerpc/safe-indirect-jump-2.c: Change expected
> assembly output from . to $.
> * gcc.target/powerpc/safe-indirect-jump-3.c: Likewise.
> * gcc.target/powerpc/safe-indirect-jump-8.c: Likewise.
>
>
> Index: gcc/config/rs6000/rs6000.md
> ===================================================================
> --- gcc/config/rs6000/rs6000.md (revision 256894)
> +++ gcc/config/rs6000/rs6000.md (working copy)
> @@ -10987,7 +10987,7 @@
> return \"b%T0\";
> else
> /* Can use CR0 since it is volatile across sibcalls. */
> - return \"crset eq\;beq%T0-\;b .\";
> + return \"crset eq\;beq%T0-\;b $\";
> }
> else if (DEFAULT_ABI == ABI_V4 && flag_pic)
> {
> @@ -11044,7 +11044,7 @@
> return \"b%T1\";
> else
> /* Can use CR0 since it is volatile across sibcalls. */
> - return \"crset eq\;beq%T1-\;b .\";
> + return \"crset eq\;beq%T1-\;b $\";
> }
> else if (DEFAULT_ABI == ABI_V4 && flag_pic)
> {
> @@ -12566,7 +12566,7 @@
> [(set (pc) (match_operand:P 0 "register_operand" "c,*l"))
> (clobber (match_operand:CC 1 "cc_reg_operand" "=y,y"))]
> "!rs6000_speculate_indirect_jumps"
> - "crset %E1\;beq%T0- %1\;b ."
> + "crset %E1\;beq%T0- %1\;b $"
> [(set_attr "type" "jmpreg")
> (set_attr "length" "12")])
>
> @@ -12672,7 +12672,7 @@
> (use (label_ref (match_operand 1)))
> (clobber (match_operand:CC 2 "cc_reg_operand" "=y,y"))]
> "!rs6000_speculate_indirect_jumps"
> - "crset %E2\;beq%T0- %2\;b ."
> + "crset %E2\;beq%T0- %2\;b $"
> [(set_attr "type" "jmpreg")
> (set_attr "length" "12")])
>
> Index: gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-2.c
> ===================================================================
> --- gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-2.c (revision
> 256894)
> +++ gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-2.c (working copy)
> @@ -30,4 +30,4 @@ int foo (int x)
>
> /* { dg-final { scan-assembler "crset 30" } } */
> /* { dg-final { scan-assembler "beqctr- 7" } } */
> -/* { dg-final { scan-assembler "b ." } } */
> +/* { dg-final { scan-assembler "b $" } } */
> Index: gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-3.c
> ===================================================================
> --- gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-3.c (revision
> 256894)
> +++ gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-3.c (working copy)
> @@ -49,4 +49,4 @@ int foo (int x)
>
> /* { dg-final { scan-assembler "crset 30" } } */
> /* { dg-final { scan-assembler "beqctr- 7" } } */
> -/* { dg-final { scan-assembler "b ." } } */
> +/* { dg-final { scan-assembler "b $" } } */
> Index: gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-8.c
> ===================================================================
> --- gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-8.c (revision
> 256894)
> +++ gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-8.c (working copy)
> @@ -12,4 +12,4 @@ int bar ()
>
> /* { dg-final { scan-assembler "crset eq" } } */
> /* { dg-final { scan-assembler "beqctr-" } } */
> -/* { dg-final { scan-assembler "b ." } } */
> +/* { dg-final { scan-assembler "b $" } } */
> Index: gcc/config/rs6000/rs6000.md
> ===================================================================
> --- gcc/config/rs6000/rs6000.md (revision 256894)
> +++ gcc/config/rs6000/rs6000.md (working copy)
> @@ -10987,7 +10987,7 @@
> return \"b%T0\";
> else
> /* Can use CR0 since it is volatile across sibcalls. */
> - return \"crset eq\;beq%T0-\;b .\";
> + return \"crset eq\;beq%T0-\;b $\";
> }
> else if (DEFAULT_ABI == ABI_V4 && flag_pic)
> {
> @@ -11044,7 +11044,7 @@
> return \"b%T1\";
> else
> /* Can use CR0 since it is volatile across sibcalls. */
> - return \"crset eq\;beq%T1-\;b .\";
> + return \"crset eq\;beq%T1-\;b $\";
> }
> else if (DEFAULT_ABI == ABI_V4 && flag_pic)
> {
> @@ -12566,7 +12566,7 @@
> [(set (pc) (match_operand:P 0 "register_operand" "c,*l"))
> (clobber (match_operand:CC 1 "cc_reg_operand" "=y,y"))]
> "!rs6000_speculate_indirect_jumps"
> - "crset %E1\;beq%T0- %1\;b ."
> + "crset %E1\;beq%T0- %1\;b $"
> [(set_attr "type" "jmpreg")
> (set_attr "length" "12")])
>
> @@ -12672,7 +12672,7 @@
> (use (label_ref (match_operand 1)))
> (clobber (match_operand:CC 2 "cc_reg_operand" "=y,y"))]
> "!rs6000_speculate_indirect_jumps"
> - "crset %E2\;beq%T0- %2\;b ."
> + "crset %E2\;beq%T0- %2\;b $"
> [(set_attr "type" "jmpreg")
> (set_attr "length" "12")])
>
> Index: gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-2.c
> ===================================================================
> --- gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-2.c (revision
> 256894)
> +++ gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-2.c (working copy)
> @@ -30,4 +30,4 @@ int foo (int x)
>
> /* { dg-final { scan-assembler "crset 30" } } */
> /* { dg-final { scan-assembler "beqctr- 7" } } */
> -/* { dg-final { scan-assembler "b ." } } */
> +/* { dg-final { scan-assembler "b $" } } */
> Index: gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-3.c
> ===================================================================
> --- gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-3.c (revision
> 256894)
> +++ gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-3.c (working copy)
> @@ -49,4 +49,4 @@ int foo (int x)
>
> /* { dg-final { scan-assembler "crset 30" } } */
> /* { dg-final { scan-assembler "beqctr- 7" } } */
> -/* { dg-final { scan-assembler "b ." } } */
> +/* { dg-final { scan-assembler "b $" } } */
> Index: gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-8.c
> ===================================================================
> --- gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-8.c (revision
> 256894)
> +++ gcc/testsuite/gcc.target/powerpc/safe-indirect-jump-8.c (working copy)
> @@ -12,4 +12,4 @@ int bar ()
>
> /* { dg-final { scan-assembler "crset eq" } } */
> /* { dg-final { scan-assembler "beqctr-" } } */
> -/* { dg-final { scan-assembler "b ." } } */
> +/* { dg-final { scan-assembler "b $" } } */
>
