diff options
Diffstat (limited to 'gcc/optabs.c')
| -rw-r--r-- | gcc/optabs.c | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/gcc/optabs.c b/gcc/optabs.c index 8ad7f4b..1820b91 100644 --- a/gcc/optabs.c +++ b/gcc/optabs.c @@ -6484,6 +6484,48 @@ expand_memory_blockage (void) expand_asm_memory_blockage (); } +/* Generate asm volatile("" : : : "memory") as a memory blockage, at the + same time clobbering the register set specified by REGS. */ + +void +expand_asm_reg_clobber_mem_blockage (HARD_REG_SET regs) +{ + rtx asm_op, clob_mem; + + unsigned int num_of_regs = 0; + for (unsigned int i = 0; i < FIRST_PSEUDO_REGISTER; i++) + if (TEST_HARD_REG_BIT (regs, i)) + num_of_regs++; + + asm_op = gen_rtx_ASM_OPERANDS (VOIDmode, "", "", 0, + rtvec_alloc (0), rtvec_alloc (0), + rtvec_alloc (0), UNKNOWN_LOCATION); + MEM_VOLATILE_P (asm_op) = 1; + + rtvec v = rtvec_alloc (num_of_regs + 2); + + clob_mem = gen_rtx_SCRATCH (VOIDmode); + clob_mem = gen_rtx_MEM (BLKmode, clob_mem); + clob_mem = gen_rtx_CLOBBER (VOIDmode, clob_mem); + + RTVEC_ELT (v, 0) = asm_op; + RTVEC_ELT (v, 1) = clob_mem; + + if (num_of_regs > 0) + { + unsigned int j = 2; + for (unsigned int i = 0; i < FIRST_PSEUDO_REGISTER; i++) + if (TEST_HARD_REG_BIT (regs, i)) + { + RTVEC_ELT (v, j) = gen_rtx_CLOBBER (VOIDmode, regno_reg_rtx[i]); + j++; + } + gcc_assert (j == (num_of_regs + 2)); + } + + emit_insn (gen_rtx_PARALLEL (VOIDmode, v)); +} + /* This routine will either emit the mem_thread_fence pattern or issue a sync_synchronize to generate a fence for memory model MEMMODEL. */ |