| Message ID | CACUk7=UvsmX4Tm9aHZ4MA2yV-FNw6NVtnRMYk0e9MZgS=N5wJQ@mail.gmail.com |
|---|---|
| State | Accepted |
| Headers | show |
Hi Uli, Apologies for the delayed response. > > Shouldn't the check be implemented along the following lines? > > if (memsize == 32 && (align % 32) == 0) > align_bits = 256; > else if ((memsize == 16 || memsize == 32) && (align % 16) == 0) > align_bits = 128; > else if (memsize >= 8 && (align % 8) == 0) > align_bits = 64; > else > align_bits = 0; This looks OK to me. Looking at the ISA documents and the variants of the vldn instructions your summary is correct. The alignment specifier should not be greater than the memory size being transferred and checking this in this form is OK . regards, Ramana > > Bye, > Ulrich > > -- > Dr. Ulrich Weigand > GNU Toolchain for Linux on System z and Cell BE > Ulrich.Weigand@de.ibm.com >
Index: gcc/config/arm/arm.c =================================================================== --- gcc/config/arm/arm.c (revision 183333) +++ gcc/config/arm/arm.c (working copy) @@ -17711,9 +17711,9 @@ /* Only certain alignment specifiers are supported by the hardware. */ if (memsize == 16 && (align % 32) == 0) align_bits = 256; - else if ((memsize == 8 || memsize == 16) && (align % 16) == 0) + else if (memsize == 16 && (align % 16) == 0) align_bits = 128; - else if ((align % 8) == 0) + else if (memsize >= 8 && (align % 8) == 0) align_bits = 64; else align_bits = 0;
Hi, PR51819 is a case where we were actually putting out alignment hints for the wrong memory size. The attached patch corrects this and another latent issue that I spotted. Committed after testing on arm-linux-gnueabi with Neon configurations. cheers Ramana 2012-01-20 Ramana Radhakrishnan <ramana.radhakrishnan@linaro.org> PR target/51819 * config/arm/arm.c (arm_print_operand): Correct output of alignment hints for neon loads and stores.