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| author | Richard Kenner <kenner@gcc.gnu.org> | 1996-09-14 17:02:23 -0400 |
|---|---|---|
| committer | Richard Kenner <kenner@gcc.gnu.org> | 1996-09-14 17:02:23 -0400 |
| commit | 8dfe5673a08e6d48ee0820c7669b8651e19e905f (patch) | |
| tree | 1cd425566dda133f77983ee3cbc86690530910c0 /gcc | |
| parent | 578b58f55e206934fd5df07a8840fb38652398b5 (diff) | |
| download | gcc-8dfe5673a08e6d48ee0820c7669b8651e19e905f.zip gcc-8dfe5673a08e6d48ee0820c7669b8651e19e905f.tar.gz gcc-8dfe5673a08e6d48ee0820c7669b8651e19e905f.tar.bz2 | |
({function,ix86_expand}_prologue): Use __alloca to allocate stack if
desired and beyond CHECK_STACK_LIMIT in size.
From-SVN: r12709
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/config/i386/i386.c | 36 |
1 files changed, 29 insertions, 7 deletions
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c index 8c7569f..af2562b 100644 --- a/gcc/config/i386/i386.c +++ b/gcc/config/i386/i386.c @@ -45,6 +45,10 @@ Boston, MA 02111-1307, USA. */ even if the conditional was untrue. */ #endif +#ifndef CHECK_STACK_LIMIT +#define CHECK_STACK_LIMIT -1 +#endif + enum reg_mem /* Type of an operand for ix86_{binary,unary}_operator_ok */ { reg_p, @@ -1742,14 +1746,25 @@ function_prologue (file, size) xops[0] = stack_pointer_rtx; xops[1] = frame_pointer_rtx; xops[2] = GEN_INT (tsize); + if (frame_pointer_needed) { output_asm_insn ("push%L1 %1", xops); output_asm_insn (AS2 (mov%L0,%0,%1), xops); } - if (tsize) + if (tsize == 0) + ; + else if (! TARGET_STACK_PROBE || tsize < CHECK_STACK_LIMIT) output_asm_insn (AS2 (sub%L0,%2,%0), xops); + else + { + xops[3] = gen_rtx (REG, SImode, 0); + output_asm_insn (AS2 (mov%L0,%2,%3), xops); + + xops[3] = gen_rtx (SYMBOL_REF, Pmode, "_alloca"); + output_asm_insn (AS1 (call,%P3), xops); + } /* Note If use enter it is NOT reversed args. This one is not reversed from intel!! @@ -1820,12 +1835,19 @@ ix86_expand_prologue () emit_move_insn (xops[1], xops[0]); } - if (tsize) - emit_insn (gen_rtx (SET, SImode, - xops[0], - gen_rtx (MINUS, SImode, - xops[0], - xops[2]))); + if (tsize == 0) + ; + else if (! TARGET_STACK_PROBE || tsize < CHECK_STACK_LIMIT) + emit_insn (gen_subsi3 (xops[0], xops[0], xops[2])); + else + { + xops[3] = gen_rtx (REG, SImode, 0); + emit_move_insn (xops[3], xops[2]); + xops[3] = gen_rtx (MEM, FUNCTION_MODE, + gen_rtx (SYMBOL_REF, Pmode, "_alloca")); + emit_call_insn (gen_rtx (CALL, VOIDmode, + xops[3], const0_rtx)); + } /* Note If use enter it is NOT reversed args. This one is not reversed from intel!! |