Hi, first of all, sorry for the delay. We quickly entered stage 4 and I thought it was best waiting for stage 1 to update you on this.
> From: gcc-patches-ow...@gcc.gnu.org [mailto:gcc-patches- > ow...@gcc.gnu.org] On Behalf Of Thomas Preud'homme > > Of course both approaches are not exclusive. I'll try to test with *both* > rs6000 bootstrap and with a cross-compiler for one of these targets. I did two experiments where I checked the impact of removing the code guarded by SHORT_IMMEDIATES_SIGN_EXTEND. In the first one I removed the code in both rtlanal.c and combine.c. In the second, I only removed the code from combine.c (in both occurences). In both cases powerpc bootstrap succeeded. I then proceeded to use these 2 produced compilers to compile the same gcc source (actually the source from removing all code guarded by the macro). I compared the output of objdump on the resulting g++ and found that in both case the output was different from the one without any modification. Both diffs look like: Disassembly of section .init: @@ -1359,7 +1359,7 @@ Disassembly of section .text: 10003a94: f8 21 ff 81 stdu r1,-128(r1) 10003a98: eb e4 00 00 ld r31,0(r4) 10003a9c: 3c 82 ff f8 addis r4,r2,-8 - 10003aa0: 38 84 d7 60 addi r4,r4,-10400 + 10003aa0: 38 84 d7 70 addi r4,r4,-10384 10003aa4: 7f e3 fb 78 mr r3,r31 10003aa8: 4b ff f0 d9 bl 10002b80 <0000003d.plt_call.strcmp@@GLIBC_2.3+0> 10003aac: e8 41 00 28 ld r2,40(r1) @@ -1371,7 +1371,7 @@ Disassembly of section .text: 10003ac4: 79 2a ff e3 rldicl. r10,r9,63,63 10003ac8: 41 82 00 78 beq- 10003b40 <._ZL22sanitize_spec_functioniPPKc+0xc0> 10003acc: 3c 62 ff f8 addis r3,r2,-8 - 10003ad0: 38 63 f5 70 addi r3,r3,-2704 + 10003ad0: 38 63 f5 b0 addi r3,r3,-2640 10003ad4: 38 21 00 80 addi r1,r1,128 10003ad8: e8 01 00 10 ld r0,16(r1) 10003adc: eb e1 ff f8 ld r31,-8(r1) (this one is when comparing g++ compiled by GCC with partial removal of the code guarded by the macro compared to compiled without GCC being modified. I may have done a mistake when doing the experiment though and can do it again if you wish. Best regards, Thomas
