diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 4218dca0d2af57ee6ff0413de1c679babc16b9fb..ec64ac249204fc10042e60995829691bb6d73591 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2009-04-22 Kazu Hirata <kazu@codesourcery.com> + + * config/arm/arm.c (arm_size_rtx_costs): Treat a PLUS with a shift + the same as a PLUS without a shift. Increase the cost of a + CONST_INT in MULT. + 2009-04-22 Manuel Lopez-Ibanez <manu@gcc.gnu.org> * Makefile.in: Update dependencies. diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c index 80d12676ca00913d1fd19d18ec6b23d9fc0869c9..547e7602f368eaa3aee4790517ed7efa337a0b47 100644 --- a/gcc/config/arm/arm.c +++ b/gcc/config/arm/arm.c @@ -5681,6 +5681,16 @@ arm_size_rtx_costs (rtx x, enum rtx_code code, enum rtx_code outer_code, return false; } + /* A shift as a part of ADD costs nothing. */ + if (GET_CODE (XEXP (x, 0)) == MULT + && power_of_two_operand (XEXP (XEXP (x, 0), 1), SImode)) + { + *total = COSTS_N_INSNS (TARGET_THUMB2 ? 2 : 1); + *total += rtx_cost (XEXP (XEXP (x, 0), 0), code, false); + *total += rtx_cost (XEXP (x, 1), code, false); + return true; + } + /* Fall through */ case AND: case XOR: case IOR: if (mode == SImode) @@ -5774,7 +5784,10 @@ arm_size_rtx_costs (rtx x, enum rtx_code code, enum rtx_code outer_code, case CONST_INT: if (const_ok_for_arm (INTVAL (x))) - *total = COSTS_N_INSNS (outer_code == SET ? 1 : 0); + /* A multiplication by a constant requires another instruction + to load the constant to a register. */ + *total = COSTS_N_INSNS ((outer_code == SET || outer_code == MULT) + ? 1 : 0); else if (const_ok_for_arm (~INTVAL (x))) *total = COSTS_N_INSNS (outer_code == AND ? 0 : 1); else if (const_ok_for_arm (-INTVAL (x)))