Re: Mark more constants readonly
On 05/27/2014 04:57 PM, Richard Biener wrote: On Tue, May 27, 2014 at 3:13 PM, Bernd Schmidt ber...@codesourcery.com wrote: I noticed that string constants built by the Fortran frontend don't set TREE_READONLY for STRING_CST (and subsequently noticed that nothing seems to set it for COMPLEX_CST). That was confusing the ptx backend I'm working on. The -fwritable-strings option for C was removed a while ago, so I tested the following patch to just set the flag unconditionally, and passed bootstrap and test on x86_64-linux. Ok? Hmm? Not so obvious. TREE_READONLY has no purpose on tcc_constant nodes if I read documentation correctly (tree.h). In fact base.readonly_flag is unused for tcc_constant (and would be redundant with TREE_CONSTANT). Well, the C frontend still sets it for strings (in fix_string_type), and gcc.dg/lvalue-5.c fails if that is removed. So things are a little inconsistent between frontends. Bernd
Re: Mark more constants readonly
On Wed, May 28, 2014 at 12:00 PM, Bernd Schmidt ber...@codesourcery.com wrote: On 05/27/2014 04:57 PM, Richard Biener wrote: On Tue, May 27, 2014 at 3:13 PM, Bernd Schmidt ber...@codesourcery.com wrote: I noticed that string constants built by the Fortran frontend don't set TREE_READONLY for STRING_CST (and subsequently noticed that nothing seems to set it for COMPLEX_CST). That was confusing the ptx backend I'm working on. The -fwritable-strings option for C was removed a while ago, so I tested the following patch to just set the flag unconditionally, and passed bootstrap and test on x86_64-linux. Ok? Hmm? Not so obvious. TREE_READONLY has no purpose on tcc_constant nodes if I read documentation correctly (tree.h). In fact base.readonly_flag is unused for tcc_constant (and would be redundant with TREE_CONSTANT). Well, the C frontend still sets it for strings (in fix_string_type), and gcc.dg/lvalue-5.c fails if that is removed. So things are a little inconsistent between frontends. Then fix that instead. The ptx backend shouldn't use TREE_READONLY on tcc_constant, so you can resolve the issue completely within the ptx backend anyway. Richard. Bernd
Mark more constants readonly
I noticed that string constants built by the Fortran frontend don't set TREE_READONLY for STRING_CST (and subsequently noticed that nothing seems to set it for COMPLEX_CST). That was confusing the ptx backend I'm working on. The -fwritable-strings option for C was removed a while ago, so I tested the following patch to just set the flag unconditionally, and passed bootstrap and test on x86_64-linux. Ok? Bernd * tree.c (build_string, build_complex): Set TREE_READONLY. diff --git a/gcc/tree.c b/gcc/tree.c index 22b92f3..067f15a 100644 --- a/gcc/tree.c +++ b/gcc/tree.c @@ -1755,6 +1755,7 @@ build_string (int len, const char *str) memset (s, 0, sizeof (struct tree_typed)); TREE_SET_CODE (s, STRING_CST); TREE_CONSTANT (s) = 1; + TREE_READONLY (s) = 1; TREE_STRING_LENGTH (s) = len; memcpy (s-string.str, str, len); s-string.str[len] = '\0'; @@ -1776,6 +1777,7 @@ build_complex (tree type, tree real, tree imag) TREE_IMAGPART (t) = imag; TREE_TYPE (t) = type ? type : build_complex_type (TREE_TYPE (real)); TREE_OVERFLOW (t) = TREE_OVERFLOW (real) | TREE_OVERFLOW (imag); + TREE_READONLY (t) = 1; return t; }
Re: Mark more constants readonly
On Tue, May 27, 2014 at 3:13 PM, Bernd Schmidt ber...@codesourcery.com wrote: I noticed that string constants built by the Fortran frontend don't set TREE_READONLY for STRING_CST (and subsequently noticed that nothing seems to set it for COMPLEX_CST). That was confusing the ptx backend I'm working on. The -fwritable-strings option for C was removed a while ago, so I tested the following patch to just set the flag unconditionally, and passed bootstrap and test on x86_64-linux. Ok? Hmm? Not so obvious. TREE_READONLY has no purpose on tcc_constant nodes if I read documentation correctly (tree.h). In fact base.readonly_flag is unused for tcc_constant (and would be redundant with TREE_CONSTANT). Richard. Bernd
