diff mbox

[arm-embedded,embedded-6-branch] Remove ARMv7E-M FPV4-SP-D16 build from rmprofile multilib

Message ID 8ee4d3d3-b3d7-8348-9faa-a953d177fb4b@foss.arm.com
State New
Headers show

Commit Message

Thomas Preudhomme July 10, 2017, 2:16 p.m. UTC 
Hi,

The new instructions in FPV5-SP-D16 compared to FPv4-SP-D16 are not
generated when building libgcc, newlib of libstdc++ such that libgcc.a,
libc.a and libstdc++.a have the same objdump output for these two
variants. It is therefore a waste of build time to be building a
multilib for ARMv7E-M FPV5-SP-D16 when selecting rmprofile multilib
variant. This patch applied to embedded-6-branch removes that multilib
and map FPv5-SP-D16 to FPv4-SP-D16.

ChangeLog entry is as follows:

*** gcc/ChangeLog.arm ***

2017-07-04  Thomas Preud'homme  <thomas.preudhomme@arm.com>

	* config/arm/t-rmprofile: Remove multilibs for fpv5-sp-d16 and map it to
	fpv4-sp-d16.

Tested by configuring GCC with --with-multilib-list=rmprofile, building it and 
running the following:

% ./install/bin/arm-none-eabi-gcc -march=armv7e-m -mfpu=fpv5-sp-d16 
-mfloat-abi=hard -print-multi-directory 

thumb/v7e-m/fpv4-sp/hard

% ./install/bin/arm-none-eabi-gcc -march=armv7e-m -mfpu=fpv5-sp-d16 
-mfloat-abi=softfp -print-multi-directory 

thumb/v7e-m/fpv4-sp/softfp

Best regards,

Thomas

Comments

Thomas Preudhomme July 10, 2017, 2:59 p.m. UTC | #1 
Likewise for embedded-7-branch.

Best regards,

Thomas

On 10/07/17 15:16, Thomas Preudhomme wrote:
> Hi,
> 
> The new instructions in FPV5-SP-D16 compared to FPv4-SP-D16 are not
> generated when building libgcc, newlib of libstdc++ such that libgcc.a,
> libc.a and libstdc++.a have the same objdump output for these two
> variants. It is therefore a waste of build time to be building a
> multilib for ARMv7E-M FPV5-SP-D16 when selecting rmprofile multilib
> variant. This patch applied to embedded-6-branch removes that multilib
> and map FPv5-SP-D16 to FPv4-SP-D16.
> 
> ChangeLog entry is as follows:
> 
> *** gcc/ChangeLog.arm ***
> 
> 2017-07-04  Thomas Preud'homme  <thomas.preudhomme@arm.com>
> 
>      * config/arm/t-rmprofile: Remove multilibs for fpv5-sp-d16 and map it to
>      fpv4-sp-d16.
> 
> Tested by configuring GCC with --with-multilib-list=rmprofile, building it and 
> running the following:
> 
> % ./install/bin/arm-none-eabi-gcc -march=armv7e-m -mfpu=fpv5-sp-d16 
> -mfloat-abi=hard -print-multi-directory
> thumb/v7e-m/fpv4-sp/hard
> 
> % ./install/bin/arm-none-eabi-gcc -march=armv7e-m -mfpu=fpv5-sp-d16 
> -mfloat-abi=softfp -print-multi-directory
> thumb/v7e-m/fpv4-sp/softfp
> 
> Best regards,
> 
> Thomas
diff mbox

Patch

diff --git a/gcc/config/arm/t-rmprofile b/gcc/config/arm/t-rmprofile
index 93aa909b4d942ad9875a95e0d4397ff17b317905..0f3742009b1459f14d5ebbaaeb0fd080e79c8acb 100644
--- a/gcc/config/arm/t-rmprofile
+++ b/gcc/config/arm/t-rmprofile
@@ -74,8 +74,6 @@  MULTILIB_REQUIRED      += mthumb/march=armv7e-m/mfpu=fpv4-sp-d16/mfloat-abi=soft
 MULTILIB_REQUIRED      += mthumb/march=armv7e-m/mfpu=fpv4-sp-d16/mfloat-abi=hard
 MULTILIB_REQUIRED      += mthumb/march=armv7e-m/mfpu=fpv5-d16/mfloat-abi=softfp
 MULTILIB_REQUIRED      += mthumb/march=armv7e-m/mfpu=fpv5-d16/mfloat-abi=hard
-MULTILIB_REQUIRED      += mthumb/march=armv7e-m/mfpu=fpv5-sp-d16/mfloat-abi=softfp
-MULTILIB_REQUIRED      += mthumb/march=armv7e-m/mfpu=fpv5-sp-d16/mfloat-abi=hard
 
 # ARMv8-M Mainline
 MULTILIB_REQUIRED      += mthumb/march=armv8-m.main
@@ -174,3 +172,7 @@  MULTILIB_REUSE         += mthumb/march.armv7/mfpu.vfpv3-d16/mfloat-abi.softfp=ma
 MULTILIB_REUSE         += mthumb/march.armv7/mfpu.vfpv3-d16/mfloat-abi.hard=march.armv7/mfpu.fpv5-d16/mfloat-abi.hard
 MULTILIB_REUSE         += mthumb/march.armv7/mfpu.vfpv3-d16/mfloat-abi.softfp=mthumb/march.armv7/mfpu.fpv5-d16/mfloat-abi.softfp
 MULTILIB_REUSE         += mthumb/march.armv7/mfpu.vfpv3-d16/mfloat-abi.hard=mthumb/march.armv7/mfpu.fpv5-d16/mfloat-abi.hard
+
+# Map ARMv7E-M FPV5-SP-D16 to FPV4-SP-D16
+MULTILIB_REUSE         += mthumb/march.armv7e-m/mfpu.fpv4-sp-d16/mfloat-abi.softfp=mthumb/march.armv7e-m/mfpu.fpv5-sp-d16/mfloat-abi.softfp
+MULTILIB_REUSE         += mthumb/march.armv7e-m/mfpu.fpv4-sp-d16/mfloat-abi.hard=mthumb/march.armv7e-m/mfpu.fpv5-sp-d16/mfloat-abi.hard