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