From 6f0a6218e31cbfe8912fa90d74f1d43ceaeed336 Mon Sep 17 00:00:00 2001 From: Thomas Preud'homme Date: Wed, 14 Jan 2015 11:51:40 +0000 Subject: [PATCH] re PR target/64453 (Live high register not saved in function prolog on ARM with -Os) 2015-01-14 Thomas Preud'homme gcc/ PR target/64453 * config/arm/arm.c (callee_saved_reg_p): Define. (arm_compute_save_reg0_reg12_mask): Use callee_saved_reg_p to check if register is callee saved instead of !call_used_regs[reg]. (thumb1_compute_save_reg_mask): Likewise. gcc/testsuite/ PR target/64453 * gcc.target/arm/pr64453.c: New. From-SVN: r219592 --- gcc/ChangeLog | 8 ++++++++ gcc/config/arm/arm.c | 17 ++++++++++++----- gcc/testsuite/ChangeLog | 5 +++++ gcc/testsuite/gcc.target/arm/pr64453.c | 9 +++++++++ 4 files changed, 34 insertions(+), 5 deletions(-) create mode 100644 gcc/testsuite/gcc.target/arm/pr64453.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 96ef507517b..4472ed2b6b3 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +2015-01-14 Thomas Preud'homme + + PR target/64453 + * config/arm/arm.c (callee_saved_reg_p): Define. + (arm_compute_save_reg0_reg12_mask): Use callee_saved_reg_p to check if + register is callee saved instead of !call_used_regs[reg]. + (thumb1_compute_save_reg_mask): Likewise. + 2015-01-14 Hale Wang * config/arm/arm.c: Tune the max_cond_insns/branch_cost for diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c index 1a190117912..237211a1f6d 100644 --- a/gcc/config/arm/arm.c +++ b/gcc/config/arm/arm.c @@ -19033,6 +19033,14 @@ output_ascii_pseudo_op (FILE *stream, const unsigned char *p, int len) fputs ("\"\n", stream); } +/* Whether a register is callee saved or not. This is necessary because high + registers are marked as caller saved when optimizing for size on Thumb-1 + targets despite being callee saved in order to avoid using them. */ +#define callee_saved_reg_p(reg) \ + (!call_used_regs[reg] \ + || (TARGET_THUMB1 && optimize_size \ + && reg >= FIRST_HI_REGNUM && reg <= LAST_HI_REGNUM)) + /* Compute the register save mask for registers 0 through 12 inclusive. This code is used by arm_compute_save_reg_mask. */ @@ -19093,7 +19101,7 @@ arm_compute_save_reg0_reg12_mask (void) /* In the normal case we only need to save those registers which are call saved and which are used by this function. */ for (reg = 0; reg <= 11; reg++) - if (df_regs_ever_live_p (reg) && ! call_used_regs[reg]) + if (df_regs_ever_live_p (reg) && callee_saved_reg_p (reg)) save_reg_mask |= (1 << reg); /* Handle the frame pointer as a special case. */ @@ -19257,7 +19265,7 @@ thumb1_compute_save_reg_mask (void) mask = 0; for (reg = 0; reg < 12; reg ++) - if (df_regs_ever_live_p (reg) && !call_used_regs[reg]) + if (df_regs_ever_live_p (reg) && callee_saved_reg_p (reg)) mask |= 1 << reg; if (flag_pic @@ -19290,7 +19298,7 @@ thumb1_compute_save_reg_mask (void) if (reg * UNITS_PER_WORD <= (unsigned) arm_size_return_regs ()) reg = LAST_LO_REGNUM; - if (! call_used_regs[reg]) + if (callee_saved_reg_p (reg)) mask |= 1 << reg; } @@ -27230,8 +27238,7 @@ arm_conditional_register_usage (void) /* When optimizing for size on Thumb-1, it's better not to use the HI regs, because of the overhead of stacking them. */ - for (regno = FIRST_HI_REGNUM; - regno <= LAST_HI_REGNUM; ++regno) + for (regno = FIRST_HI_REGNUM; regno <= LAST_HI_REGNUM; ++regno) fixed_regs[regno] = call_used_regs[regno] = 1; } diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index e2929d3d42f..6429922d59f 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2015-01-14 Thomas Preud'homme + + PR target/64453 + * gcc.target/arm/pr64453.c: New. + 2015-01-14 Richard Biener PR lto/64415 diff --git a/gcc/testsuite/gcc.target/arm/pr64453.c b/gcc/testsuite/gcc.target/arm/pr64453.c new file mode 100644 index 00000000000..17155afc9d7 --- /dev/null +++ b/gcc/testsuite/gcc.target/arm/pr64453.c @@ -0,0 +1,9 @@ +/* { dg-do compile } */ +/* { dg-options "-mthumb -Os " } */ +/* { dg-require-effective-target arm_thumb1_ok } */ + +void save_regs () { + __asm volatile ("" ::: "r8"); +} + +/* { dg-final { scan-assembler "\tmov\tr., r8" } } */ -- 2.30.2