From: Xi Ruoyao <xry111@xry111.site>
To: gcc-patches@gcc.gnu.org
Cc: chenglulu <chenglulu@loongson.cn>,
i@xen0n.name, xuchenghua@loongson.cn, c@jia.je,
Xi Ruoyao <xry111@xry111.site>
Subject: [PATCH] LoongArch: Fix infinite secondary reloading of FCCmode [PR113148]
Date: Wed, 27 Dec 2023 06:37:20 +0800 [thread overview]
Message-ID: <20231226223818.128525-1-xry111@xry111.site> (raw)
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
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)
+ ;
+}
--
2.43.0
next reply other threads:[~2023-12-26 22:38 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-12-26 22:37 Xi Ruoyao [this message]
2023-12-27 6:08 ` chenglulu
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