LoongArch: Fix infinite secondary reloading of FCCmode [PR113148]
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Commit Message
The GCC internal doc says:
X might be a pseudo-register or a 'subreg' of a pseudo-register,
which could either be in a hard register or in memory. Use
'true_regnum' to find out; it will return -1 if the pseudo is in
memory and the hard register number if it is in a register.
So "MEM_P (x)" is not enough for checking if we are reloading from/to
the memory. This bug has caused reload pass to stall and finally ICE
complaining with "maximum number of generated reload insns per insn
achieved", since r14-6814.
Check if "true_regnum (x)" is -1 besides "MEM_P (x)" to fix the issue.
gcc/ChangeLog:
PR target/113148
* config/loongarch/loongarch.cc (loongarch_secondary_reload):
Check if regno == -1 besides MEM_P (x) for reloading FCCmode
from/to FPR to/from memory.
gcc/testsuite/ChangeLog:
PR target/113148
* gcc.target/loongarch/pr113148.c: New test.
---
Bootstrapped & regtested on loongarch64-linux-gnu. Ok for trunk?
gcc/config/loongarch/loongarch.cc | 3 +-
gcc/testsuite/gcc.target/loongarch/pr113148.c | 44 +++++++++++++++++++
2 files changed, 46 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gcc.target/loongarch/pr113148.c
Comments
在 2023/12/27 上午6:37, Xi Ruoyao 写道:
> The GCC internal doc says:
>
> X might be a pseudo-register or a 'subreg' of a pseudo-register,
> which could either be in a hard register or in memory. Use
> 'true_regnum' to find out; it will return -1 if the pseudo is in
> memory and the hard register number if it is in a register.
>
> So "MEM_P (x)" is not enough for checking if we are reloading from/to
> the memory. This bug has caused reload pass to stall and finally ICE
> complaining with "maximum number of generated reload insns per insn
> achieved", since r14-6814.
>
> Check if "true_regnum (x)" is -1 besides "MEM_P (x)" to fix the issue.
>
> gcc/ChangeLog:
>
> PR target/113148
> * config/loongarch/loongarch.cc (loongarch_secondary_reload):
> Check if regno == -1 besides MEM_P (x) for reloading FCCmode
> from/to FPR to/from memory.
>
> gcc/testsuite/ChangeLog:
>
> PR target/113148
> * gcc.target/loongarch/pr113148.c: New test.
> ---
>
> Bootstrapped & regtested on loongarch64-linux-gnu. Ok for trunk?
LGTM!
Thanks!
>
> gcc/config/loongarch/loongarch.cc | 3 +-
> gcc/testsuite/gcc.target/loongarch/pr113148.c | 44 +++++++++++++++++++
> 2 files changed, 46 insertions(+), 1 deletion(-)
> create mode 100644 gcc/testsuite/gcc.target/loongarch/pr113148.c
>
> diff --git a/gcc/config/loongarch/loongarch.cc b/gcc/config/loongarch/loongarch.cc
> index 5ffd06ce9be..c0a0af3dda5 100644
> --- a/gcc/config/loongarch/loongarch.cc
> +++ b/gcc/config/loongarch/loongarch.cc
> @@ -6951,7 +6951,8 @@ loongarch_secondary_reload (bool in_p ATTRIBUTE_UNUSED, rtx x,
> return NO_REGS;
> }
>
> - if (reg_class_subset_p (rclass, FP_REGS) && MEM_P (x))
> + if (reg_class_subset_p (rclass, FP_REGS)
> + && (regno == -1 || MEM_P (x)))
> return GR_REGS;
>
> return NO_REGS;
> diff --git a/gcc/testsuite/gcc.target/loongarch/pr113148.c b/gcc/testsuite/gcc.target/loongarch/pr113148.c
> new file mode 100644
> index 00000000000..cf48e552053
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/loongarch/pr113148.c
> @@ -0,0 +1,44 @@
> +/* PR 113148: ICE caused by infinite reloading */
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -march=la464 -mfpu=64 -mabi=lp64d" } */
> +
> +struct bound
> +{
> + double max;
> +} drawQuadrant_bound;
> +double w4, innerXfromXY_y, computeBound_right_0;
> +struct arc_def
> +{
> + double w, h;
> + double a0, a1;
> +};
> +static void drawQuadrant (struct arc_def *);
> +static void
> +computeBound (struct arc_def *def, struct bound *bound)
> +{
> + double ellipsex_1, ellipsex_0;
> + bound->max = def->a1 ?: __builtin_sin (w4) * def->h;
> + if (def->a0 == 5 && def->w == def->h)
> + ;
> + else
> + ellipsex_0 = def->a0 == 0.0 ?: __builtin_cos (w4);
> + if (def->a1 == 5 && def->w == def->h)
> + ellipsex_1 = bound->max;
> + __builtin_sqrt (ellipsex_1 * innerXfromXY_y * innerXfromXY_y * w4);
> + computeBound_right_0 = ellipsex_0;
> +}
> +void
> +drawArc ()
> +{
> + struct arc_def foo;
> + for (;;)
> + drawQuadrant (&foo);
> +}
> +void
> +drawQuadrant (struct arc_def *def)
> +{
> + int y, miny;
> + computeBound (def, &drawQuadrant_bound);
> + while (y >= miny)
> + ;
> +}
@@ -6951,7 +6951,8 @@ loongarch_secondary_reload (bool in_p ATTRIBUTE_UNUSED, rtx x,
return NO_REGS;
}
- if (reg_class_subset_p (rclass, FP_REGS) && MEM_P (x))
+ if (reg_class_subset_p (rclass, FP_REGS)
+ && (regno == -1 || MEM_P (x)))
return GR_REGS;
return NO_REGS;
new file mode 100644
@@ -0,0 +1,44 @@
+/* PR 113148: ICE caused by infinite reloading */
+/* { dg-do compile } */
+/* { dg-options "-O2 -march=la464 -mfpu=64 -mabi=lp64d" } */
+
+struct bound
+{
+ double max;
+} drawQuadrant_bound;
+double w4, innerXfromXY_y, computeBound_right_0;
+struct arc_def
+{
+ double w, h;
+ double a0, a1;
+};
+static void drawQuadrant (struct arc_def *);
+static void
+computeBound (struct arc_def *def, struct bound *bound)
+{
+ double ellipsex_1, ellipsex_0;
+ bound->max = def->a1 ?: __builtin_sin (w4) * def->h;
+ if (def->a0 == 5 && def->w == def->h)
+ ;
+ else
+ ellipsex_0 = def->a0 == 0.0 ?: __builtin_cos (w4);
+ if (def->a1 == 5 && def->w == def->h)
+ ellipsex_1 = bound->max;
+ __builtin_sqrt (ellipsex_1 * innerXfromXY_y * innerXfromXY_y * w4);
+ computeBound_right_0 = ellipsex_0;
+}
+void
+drawArc ()
+{
+ struct arc_def foo;
+ for (;;)
+ drawQuadrant (&foo);
+}
+void
+drawQuadrant (struct arc_def *def)
+{
+ int y, miny;
+ computeBound (def, &drawQuadrant_bound);
+ while (y >= miny)
+ ;
+}