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Thumb2 code in LD veneers?


Is there a way to get GNU ld to use Thumb2 instructions for veneers?  Here is an example of a veneer that ld creates to insert a long call:

0800b170 <__sinf_veneer>:
 800b170:	b401      	push	{r0}
 800b172:	4802      	ldr	r0, [pc, #8]	; (800b17c <__sinf_veneer+0xc>)
 800b174:	4684      	mov	ip, r0
 800b176:	bc01      	pop	{r0}
 800b178:	4760      	bx	ip
 800b17a:	bf00      	nop
 800b17c:	00000169 	.word	0x00000169

In Thumb2 mode, the ldr instruction could have loaded the target address directly to the ip register.  This would save the push, pop, and mov instructions.

In this example, the linker is invoked by GCC [1].  I'm using GNU ld version 2.32.2 as packaged by ARM Ltd through Launchpad [2].


[1] arm-none-eabi-gcc     $(object_files)   -mcpu=cortex-m4 -O2 -ggdb -fomit-frame-pointer -falign-functions=16 -fno-math-errno -fstack-usage -fstack-protector -ffunction-sections -fdata-sections -fno-common -mfloat-abi=hard -mfpu=fpv4-sp-d16 -fsingle-precision-constant -nostartfiles -L. -Wl,-Map=build/ch.map,--cref,--no-warn-mismatch,--library-path=../../os/ports/GCC/ARMCMx,--script=../../os/ports/GCC/ARMCMx/STM32F4xx/ld/STM32F407xG_CCM_REMAPPED.ld,--gc-sections -mno-thumb-interwork -mthumb -lm  -o build/ch.elf


[2] https://launchpad.net/gcc-arm-embedded, release 4.8-2014-q1-update


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